Mesostructured Bimetallic MFI Zeolite for Efficient Aromatization of Light Naphtha to BTX Aromatics

Mesostructured Bimetallic MFI Zeolite for Efficient Aromatization of Light Naphtha to BTX Aromatics | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Mesostructured Bimetallic MFI Zeolite for Efficient Aromatization of Light Naphtha to BTX Aromatics Muhammad Waqas, Tatinaidu Kella, Ziyauddin S. Qureshi, Yaming Jin, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7408317/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 05 Dec, 2025 Read the published version in Journal of Porous Materials → Version 1 posted 10 You are reading this latest preprint version Abstract Diffusion limitations in microporous ZSM-5 zeolites hinder the efficient aromatization of light naphtha into valuable BTX (benzene, toluene, xylenes). In this work, we report the development of a mesostructured bimetallic catalyst through controlled alkaline desilication of ZSM-5 (Z5), followed by the incorporation of 2 wt.% La and 1 wt.% Zn via wet impregnation. The desilicated zeolite (Z5-AT) exhibited enhanced mesoporosity, improving molecular diffusion and boosting BTX yield from 24 wt.% (Z5) to 49 wt.%. Further metal modification significantly enhanced performance, with the optimized 2%La-1%Zn/Z5-AT catalyst achieving a BTX yield of 72.7 wt.% at 550 °C in a fixed-bed down-flow reactor. Zn incorporation enhances the Lewis-to-Brønsted acid site (L/B) ratio, which accelerates dehydrogenation activity and promotes higher BTX formation. Textural and acidity characterizations confirmed uniform metal dispersion, improved surface area, and a favorable increase in L/B ratio. In-situ pyridine-FTIR and NH 3 -TPD analyses revealed synergistic effects between La and Zn, promoting dehydrogenation, acidity tuning, and coke suppression. These results demonstrate the effectiveness of mesostructured bimetallic ZSM-5 in enhancing light naphtha aromatization, with high aromatic selectivity and improved stability. Mesostructured zeolite Bimetallic catalyst Naphtha aromatization Dehydrogenation BTX aromatics petrochemicals Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 1. Introduction BTX aromatics (benzene, toluene, and xylenes) are fundamental petrochemical intermediates widely used in the production of high-value materials, including plastics, organic solvents, and fuel additives. 1 – 3 The oil refining industry has consistently strived to enhance the output of highly valued BTX through catalytic light naphtha reforming. 4 – 5 Conventional catalytic reforming, primarily designed for heavy naphtha (C 7 -C 9 ), is efficient in converting naphthenes and paraffins to aromatics. However, its effectiveness diminishes significantly when processing light naphtha (C 5 -C 6 ) due to its low aromatic precursors and high paraffin content. Moreover, the process often results in the generation of low-value heavy aromatics (C 9+ ), which limits the selectivity toward BTX. 6 – 8 In the chemical industry, ~ 60% light naphtha (C 5 -C 6 ) is diverted to steam cracking units for olefin production (primarily ethylene), while around 30% is isomerized and blended into gasoline to meet octane requirements. 9 – 10 Therefore, the availability, consumption, and costs of naphtha have a substantial impact on profitability in the petrochemical and refining industries. 11 Light naphtha's limited usage in direct blending is also constrained by its high Reid Vapor Pressure (RVP) and low octane number, which can negatively impact gasoline volatility specifications. 8 As a result, its upgrading to more valuable chemical intermediates is gaining interest. Globally, the daily light naphtha demand is estimated at 8.8 million barrels, while gasoline consumption reaches approximately 26.1 million barrels per day, representing more than 26% of the world's total refined product market. 5 These figures underline the strategic importance of naphtha utilization efficiency in determining refinery profitability. Given the rising demand for para-xylene and benzene, particularly in the production of polyethylene terephthalate (PET), there is growing industrial and academic interest in catalytic routes for converting light naphtha into BTX aromatics. The global BTX market was valued at USD 6.73 billion in 2022 and is projected to grow at a CAGR of 5.22%, reaching USD 9.13 billion by 2028. 12 Several types of zeolites, such as mordenite, beta zeolite, ZSM-5, ZSM-11, and zeolite Y are widely recognized as efficient catalysts for transforming light naphtha into aromatic compounds. 9 , 13 Among them, ZSM-5 is particularly favored due to its high surface area, thermal stability, and well-defined microporous structure. 14 – 16 ZSM-5 that have been combined with various oxides are acknowledged as an effective material for improving aromatization selectivity. 17 – 18 The optimal aluminum content in the ZSM-5 framework enhances its acidity, thereby promoting cracking, while the metal functionality supports dehydrogenation, facilitating the conversion of olefins into aromatics. 19 – 20 Much effort has been devoted to achieving higher aromatization selectivity by utilizing various metal incorporation in the framework of ZSM-5, for instance, Zn, 21 Ag, 22 Ni, 23 Ga, 24 etc. Zinc, in particular, is considered highly effective due to its abundance, low toxicity, and strong aromatization performance. Adding other oxides of elements such as Si, 25 – 26 P, 27 , and B 28 helps to selectively passivate the external acid sites of ZSM-5, thereby shielding the BTX molecules that have generated inside the interior micropores from secondary isomerization. Additionally, by obstructing pore openings, it slightly increases the micropore channels' shape selectivity. 18 , 29 Metal-modified ZSM-5 zeolites can effectively convert light naphtha to BTX, offering enhanced selectivity and improved aromatization activity. Although surface modification of ZSM-5 with additional oxides enhances BTX selectivity, excessive blocking of pore openings can hinder aromatic diffusion and reduce overall catalytic efficiency and stability. 31 – 32 Increasing acid site availability enhances overall aromatization activity, while incorporating mesopores can mitigate carbon deposition. Designing mesostructured ZSM-5 catalysts with multiple oxide modifiers offers a promising strategy to balance the trade-off between shape-selectivity and catalytic activity. Desilication under alkaline conditions is one of the methods used to fabricate mesoporous zeolites, or the mesopores can also be created by utilizing templates and subsequent treatment protocols. 33 – 34 This study examines the diffusion limitations of bulky hydrocarbons in the micropore channels of ZSM-5 zeolite by generating homogeneous intracrystalline mesopore channels through a straightforward and efficient alkaline desilication post-treatment for catalytic upgrading of light naphtha into BTX aromatics. BET and TEM analyses confirmed mesopore formation, which facilitated improved molecular transport and enhanced diffusion of BTX aromatics during catalytic conversion of light naphtha. XRD, TEM, and SEM-EDX analyses demonstrate the uniform dispersion of zinc and lanthanum sites on mesopore ZSM-5. We used NH 3 -TPD and pyridine FT-IR to analyze the Lewis and Brønsted acidic sites and reduction characteristics of the prepared catalysts. The characterization outcomes were comprehensively analyzed, with an effort to establish correlations between physicochemical properties of the catalysts and catalytic performance in light naphtha aromatization. 2. EXPERIMENTAL SECTION 2.1. Materials ZSM-5 zeolite powder CBV 3024E with a SiO 2 /Al 2 O 3 molar ratio of 30 was procured from Zeolyst. The choice of ZSM-5 zeolite with a SiO 2 /Al 2 O 3 ratio of 30 is based on its recognition as a benchmark for regulated post-synthesis modifications aimed at achieving mesoporosity. A hydrotreated light-straight run (LSR) naphtha sample was obtained from a local refinery processing a crude oil comprising 25% Arab Light and 75% Arab Heavy. The value of sulfur in LSR naphtha was 43 parts per million (ppm), while its density was 0.676 g/cm 3 . A comprehensive hydrocarbon analyzer (Shimadzu GC-DHA) was employed to examine the concentrations of iso -paraffins, n -paraffins, olefins, aromatics, and naphthenes in LSR naphtha. Table 1 presents the components of naphtha feed with 90 wt.% paraffins. Table 1 Composition of light straight run naphtha feed. Component, wt.% n -Paraffins iso -Paraffins Naphthenes Aromatics Total C 5 25.5 8.8 2.1 0.0 36.4 C 6 25.4 26.5 5.4 1.5 58.8 C 7 0.8 3.3 0.6 0.1 4.8 Total 51.7 38.6 8.1 1.6 100 2.2. Preparation of desilicated Z5-AT zeolite The NH 4 + -form ZSM-5 zeolite was calcined in static air at 550°C for 5 h (heating rate: 5°C/min) to obtain the protonic form, designated as Z5. Alkaline desilication was performed using 0.2 M NaOH solution at a zeolite-to-solution ratio of 1 g:10 mL. The solution was stirred at 500 rpm and preheated to 80 o C prior to the addition of the zeolite. The solution was agitated for 60 minutes, then quenched, filtered, and thoroughly rinsed with distilled water until achieving neutral pH, followed by drying for 12 h at 100°C. The desilicated specimen underwent ion exchanges three consecutive times in aqueous NH 4 NO 3 of 1.0 M at a temperature of 80 o C for 4.5 hours. Subsequently, the process involved filtration, meticulous washing with distilled water, overnight drying at 100 o C, and calcining for 5 h at 550°C, which was labeled as Z5-AT. 2.3 Preparation of metal-modified Z5-AT catalysts Zinc- and lanthanum-modified mesoporous ZSM-5 catalysts were synthesized using wet impregnation and co-impregnation techniques, respectively. For single-metal catalysts, aqueous solutions of Zn (NO 3 ) 2 ·6H 2 O or La (NO 3 ) 3 ·xH 2 O were individually impregnated onto the alkali-treated Z5-AT support. In the bimetallic system, both metal precursors were simultaneously added to the support using a co-impregnation approach. The metal precursor(s) were dissolved in 100 mL of deionized water and mixed with Z5-AT in a 250 mL round-bottom flask. The mixture was stirred at 500 rpm for 3 h, followed by slow evaporation at 50°C. The dried solid material was then calcined at 550°C for 5 h. The resulting catalysts were designated as 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La–1%Zn/Z5-AT. The construction of mesopore channels on zeolite surface was achieved through a straightforward and effective alkaline treatment (desilication) strategy (Z5-AT). This was subsequently followed by Zn modification (1%Zn/Z5-AT), La modification (2%La/Z5-AT), and co-modification (2%La-1%Zn-Z5-AT), as depicted in Fig. 2 . 2.4. Catalyst Characterization. A series of parent Z5, as-synthesized alkaline Z5-AT, and metal-modified catalysts, such as 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT catalysts were characterized to study their physicochemical and surface properties. The Rigaku Miniflex II utilizes the radiation sourced from Cu K±, having a wavelength of 1.5405 Å, under the circumstances of 15 mA, 30 kV, 2° min − 1 scanning rate, 0.02° from 5° to 50° 2θ is utilized to obtain the XRD patterns of powder samples. The BET equation is utilized to measure the pore volume, or pore diameter, surface area, utilizing an ASAP-2020 Micromeritics analyzer and nitrogen adsorption at -195°C. SEM images were captured with a FESEM (Tescan Lyra-3). A 20-kV scanning electron microscope was used. EDXS analysis using LINK INCA software was used to analyze the catalyst elemental composition. Conductive copper tape concealed the specimens on a sample holder. A Cressington ion-coater with 15 mA current coats for 30 seconds in vacuum. The NH 3 -TPD testing on a Belcat-A-200 chemisorption instrument was used to measure the acidity of as-prepared catalysts. The system consists of a quartz microreactor, a thermal conductivity detector, and a gas mixing facility. All of the samples had been pre-treated with 50 mL/min of helium at 500°C for 2h. The catalyst was allowed to cool to room temperature and then fed 50 mL/min of ammonia (5% ammonia in helium) for 30 min at 100°C to saturate the acid sites. The surplus ammonia was eliminated at 100°C using a 50 mL/min helium stream for 30 minutes. Chemically adsorbed ammonia was removed by heating at 100°C to 600°C with a ramp rate of 10°C/min. A thermal conductivity detector was used to detect the released ammonia concentration. We used the EMIA-220V Horiba Carbon-Sulfur Analyzer to determine the amount of coke present in the spent catalyst. The furnace combusted approximately 10–20 mg of catalyst, incorporating tungsten as a combustion promoter, at elevated temperatures. We quantified the generated CO 2 using an infrared analyzer and represented it as a weight catalyst percentage. We evaluated acid site types using a pyridine adsorption FTIR method with a Scientific Fisher-Nicolet iS10 FTIR spectrometer. In each instance, we used a 120 mg powder sample and compressed it into a thin self-supported disc to place it in a quartz IR cell. We performed evacuation prior to the pyridine adsorption step and recorded the IR spectrum at temperatures of 150°C, 200°C, 250°C, and 300°C to use these spectra as background references. We evacuated the catalyst sample at 500°C for 30 minutes, then cooled it to 150°C. Next, we exposed the sample to pyridine vapor for 5 minutes, then evacuated it under high vacuum for 3 minutes to remove any physisorbed pyridine, and finally recorded IR spectra at 150°C. After recording, we increased the sample temperature to 200°C and obtained spectra. We repeated this process at 250°C and 300°C, ensuring consecutive evacuations at each temperature. We utilized the FTIR spectra obtained at each temperature after pyridine adsorption and evacuation to assess Brønsted and Lewis acid sites. Peaks at 1540 cm − 1 and 1450 cm − 1 correspond to pyridine adsorption on Brønsted and Lewis acid sites, respectively. Both Lewis and Brønsted sites contribute to the peak at the 1490 cm − 1 band, which we exclude from our calculations. Eq. 1 calculates the quantitative acidity (C, millimoles of acid sites per gram of the sample). 𝐶(mmol/g) = (𝐴×𝑆)/(𝐸×𝑊) Eq. (1) A (cm − 1 ) denotes the area of the IR band, S (cm 2 ) represents the pellet area, W (mg) indicates the pellet weight, and E (cm mµ −1 ) refers to the extinction coefficients, with values of 1.28 for Lewis sites and 1.13 for Brønsted sites. 2.5. Catalyst Evaluation The catalyst performance of LSR naphtha aromatization was assessed in a fixed-bed continuous flow reactor (Fig. 2 ). The reactor comprised a 316 stainless steel tube (203 mm length, 7.9 mm i.d., 3.2 mm wall thickness), packed with 0.5 g of sieved catalyst (500–1000 µm), supported between layers of silicon carbide and separated by glass wool (Table 2 ). Prior to reaction, the catalyst was pretreated at 550°C for 2h under 20 mL/min N 2 flow, following ASTM D4463 guidelines. The reactions were conducted at 550°C under atmospheric pressure, a WHSV of 1.0 h − 1, and a time-on-stream (TOS) of 1–6 h. Hydrotreated LSR naphtha was fed at 0.01–0.5 mL/min, and nitrogen was co-fed at 10 mL/min to maintain flow. The feed and reactor lines were enclosed in an oven maintained at 200°C to ensure complete vaporization. Reaction products were separated via a gas-liquid separator (-10°C), non-condensable gases were analyzed online using a four-channel Agilent Micro-GC (ASTM D7833) to quantify H 2 , N 2 , and C 1 -C 6 hydrocarbons. Liquid samples were collected hourly, weighed, and analyzed using an offline DHA-GC (PIONA column) in accordance with ASTM D6729. Systematically monitored the reaction mass balance during all catalytic tests. The calculations are based on the approximate mass of the feed and products, which encompass both liquid and non-condensable gases. Conversion was calculated based on the difference in non-aromatic hydrocarbons between feed and products. Aromatic selectivity was defined as the mass ratio of BTX to total products (normalized to 100%), and liquid yield as the mass of liquid products per mass of naphtha fed over the reaction period. Table 2 Operating parameters of the fixed-bed flow reactor system. Parameter Value Reactor temperature, °C 550 Catalyst weight in grams, sieved to 500–1000 µm particle size 0.5 Time on stream, h 1–6 Nitrogen flowrate, mL/min 10 Pressure Atmospheric Feed Light naphtha Light naphtha flowrate, mL/min 0.01 Weight hour space velocity, h − 1 1 Reactor length/ID, inch 8/0.6 3. Results and Discussion 3.1. Structural and Textural Properties. Figure 3 presents the XRD patterns of all zeolite-based catalysts. All catalysts' diffraction patterns displayed the typical feature of the MFI structure. Additionally, no diffraction peaks corresponding to La or Zn oxide phases were observed, indicating that La and Zn species are uniformly and well-dispersed on Z5. The alkali modified Z5 sample, after desilication, showed a slight decrease in relative crystallinity of 0.4% in comparison to ZSM-5 parent zeolite. This suggests that the desilication process adopted has a minor impact on the integrity of the zeolite framework. 35 The catalyst relative crystallinity decreases with the impregnation of metal(s). The relative crystallinity of bimetallic sample 2%La-1%Zn/Z5-AT decreased significantly to 36%, which can be attributed to the lattice effects caused by the deposition of metal oxide on the surface of zeolite. 36 During the alkaline treatment, partial extraction of Si and some Al from the zeolite structure framework led to Al enrichment on the external surface. As a result, aluminum atoms aggregate on the surface of zeolite, obstructing the small pores and diminishing the crystallinity of ZSM-5. 3.2. Pore Structure and Surface Properties. Figure 4 shows the N 2 adsorption-desorption isotherms and pore-size distributions of parent and as-synthesized zeolite catalysts. Compared to microporous pristine Z5, all desilicated samples (Z5-AT, 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT) exhibited increased N 2 uptake in the relative pressure (p/p 0 ) range of 0.4–0.8, confirming the effective creation of mesopores via the desilication method. As shown in Fig. 4 , the mesopores for alkali modified Z5-AT sample are centered at about 5–10 nm. Table 3 lists the specific textural features of all as-synthesized catalysts. Alkali modified Z5-AT sample has a specific surface area of 343 m 2 /g. Compared to the parent Z5, the desilicated Z5-AT exhibited relatively high specific surface areas and mesopore volumes. The BJH pore size distribution confirmed the presence of intracrystalline mesopores with a medium diameter of 6.3 nm in Z5-AT. A significant increase in the V meso /V micro ratio was observed after the impregnation of metal(s). Specifically, 1%Zn/Z5-AT and 2%La-1%Zn/Z5-AT achieved values of approximately 2, compared to 1.92 for the Z5-AT. The interaction of NO 3 and NH 3 during the nitride impregnation followed by calcination primarily facilitates desilication, which accounts for the mesoporosity. 4 The observed mesoporous characteristics could contribute to their efficacy in light naphtha aromatization. Table 3 Textural characteristics of prepared catalysts. Property Z5 Z5-AT 1%Zn/Z5-AT 2%La/Z5-AT 2%La-1%Zn/Z5-AT Surface area BET surface area (m 2 /g) 342 343 310 307 297 t -Plot micropore area (m 2 /g) 210 208 194 199 190 t -Plot external surface area (m 2 /g) 132 135 116 108 107 Pore volume Total pore volume (cm 3 /g) 0.278 0.324 0.308 0.286 0.303 t -Plot micropore volume (cm 3 /g) V micro 0.112 0.111 0.103 0.106 0.101 Mesopore volume (cm 3 /g) V meso 0.166 0.213 0.205 0.187 0.202 V meso /V micro 1.48 1.92 1.99 1.75 2.0 Average pore diameter (nm) 5.05 6.32 7.10 6.67 7.44 3.3. Acidity Measurements. The acidity of parent Z5 and modified catalysts (Z5-AT, 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT) was assessed using NH 3 -TPD analysis. The ammonia desorption is separated using Gaussian peak deconvolution and fitted into three clear peaks. The acid sites can be classified as weak, medium, or strong. 29 , 37 The profiles of NH 3 -TPD profiles, as shown in Table S1 , determine the quantities of each type of acid site. Desilication seems to slightly reduce the acidity of Z5-AT compared to the parent Z5 (Fig. 5 a and Figure S1 ). Previous findings 38 – 39 , suggest that desilication under alkaline conditions resulted in the leaching of silicon atoms, leading to the extraction of aluminum atoms. The Al atoms clustered and gathered on the exterior surface, obstructing the micro- and mesopores as Lewis acid sites. 35 , 40 When 1%Zn or 2%La species are introduced, the overall acid strength of Z5-AT drops, particularly affecting the strong-acid sites, 41 whereas the concentration of medium strong-acid sites somewhat increases (Fig. 5 b and 5 c). The addition of 2% La and 1% Zn to Z5-AT significantly enhances the overall acidity. This effect contributes to a notable shift of strong acid sites into medium-strong sites, likely as the result of the presence of the abundant Brønsted acid sites in the La-Zn/ZSM-5 sample (Fig. 5 d). 42 – 43 Figure 6 depicts the Py-FTIR spectra of all materials at four distinct temperatures from 150 o C to 300 o C, which were acquired to better assess the acidity of zeolite after desilication and metal modification. Figures 6 a and 6 b illustrate that the introduction of Zn species significantly reduces the quantity of Brønsted acid sites, concurrently enhancing the concentration of Lewis acid sites, as evidenced by a notable blue shift. These results suggest that during the Zn modification process, Zn species interact with ZSM-5 Brønsted acid sites to produce additional Lewis acid sites. 44 According to reports, the impregnated Zn species exist as [ZnOH] + ions 45 or [ZnOZn] 2+ ions, 41 that enable the conversion of Brønsted acid sites to Lewis acid sites. Following additional loading of La species, we observe a decrease in both Brønsted and Lewis acid site quantities in Figs. 6 c and 6 d. This is because the acid centers are covered by the impregnation of Zn and La oxides. 46 Desilication in alkaline environments minimally influences the acidity of zeolites when compared with the modification process, particularly for the ratio of Brønsted to Lewis acid sites. 3.4. Morphology Analysis. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the surface, shape, and size distribution of mesopores in zeolite-based materials. In Figs. 7 a and 7 d, the images obtained from SEM and TEM Z5 display that Z5 has a hexagonal crystal structure with homogeneous micropores, characteristic of ZSM-5 zeolite. 30 , 47 In Figs. 7 b and 7 e, the SEM-TEM images of Z5-AT revealed a distinctive hybrid structure containing crystals in spherical and hexagonal shapes, representing a distinct morphology. Moreover, micropores and mesopores are clearly visible throughout the material. The observations corroborate the N 2 adsorption-desorption data, indicating that the desilication process had a substantial effect on the pore structure. The TEM image in Fig. 7 f for 2%La-1%Zn/Z5-AT shows dark spots, demonstrating a uniform distribution of La and Zn species across the zeolite framework. In addition, the SAED pattern showed an amorphous nature of the material (inset bottom), which further confirms that La and Zn are well dispersed over the zeolite framework. Figure 7 g and Figure S2 present the elemental mapping data, and the EDX spectrum verifies the existence of silicon (Si), aluminum (Al), oxygen (O), lanthanum (La), and zinc (Zn) in the synthesized catalyst. Additionally, it also confirms the uniform dispersion of La and Zn inside the zeolite structure. 3.6. Catalytic Aromatization of Light Naphtha. Light naphtha aromatization was carried out in a fixed-bed reactor at 550°C and atmospheric pressure with a WHSV of 1.0 h − 1 , using the parent and modified Z5-based catalysts. Table 4 offers a comprehensive assessment of the products, highlighting their performance and characteristics. The product distribution from light naphtha aromatization is typically categorized into liquid and gaseous fractions, as illustrated in Fig. 8 a and Fig. 8 b, respectively. The liquid phase primarily consists of BTX aromatics along with C 5+ paraffins and olefins, whereas the gas phase includes C 1 , C 2 , C 2= , and C 3 -C 4 hydrocarbons. All tested catalysts Z5, Z5-AT, 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT achieved near-complete conversion (99–100%) of light straight-run (LSR) naphtha under reaction conditions of 550°C and atmospheric pressure. The parent Z5 catalyst exhibited an aromatic yield of 31.9 wt.%, while desilicated Z5-AT demonstrated a significantly enhanced aromatic yield of 49.7 wt.%, approximately 1.5 times greater than that of microporous parent Z5. Further enhancement in aromatization activity was observed for the metal-modified catalysts 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT catalysts can be attributed to a combination of: tailored acidity through metal incorporation and framework modification, (ii) enhanced dehydrogenation activity provided by Zn species, and (iii) improved mass transport from the mesoporous-microporous structure, with La contributing to acidity moderation and selectivity enhancement. Table 4 Product distribution in LSR naphtha aromatization over parent and modified ZSM-5 catalysts. Catalyst Z5 Z5-AT 1%Zn/Z5-AT 2%La/Z5-AT 2%La-1%Zn/Z5-AT Naphtha Conversion, % 99.8 99.5 100.0 99.2 100.0 Yield (wt.%) Benzene 15.0 17.3 32.2 16.8 33.6 Toluene 7.0 21.7 26.9 20.2 26.0 Xylenes 2.0 9.4 10.0 7.6 12.7 BTX 24.0 49.0 69.4 45.2 72.7 Ethyl benzene 0.0 0.6 0.3 0.6 0.4 C 9 + Aromatics 7.9 0.7 1.3 1.8 1.8 C 5 + Paraffins + Olefins 14.9 0.5 0.0 0.8 0.0 Total Aromatics 31.9 49.7 70.6 47.0 74.5 C 1 9.3 2.6 5.1 3.2 3.8 C 2 6.7 1.5 6.5 2.1 5.4 C 2 = 3.3 2.6 0.9 4.3 1.2 C 3 + C 4 33.9 43.1 16.9 42.7 15.2 Total Paraffins + Olefins 53.1 49.9 29.4 52.3 25.5 Sum 100.0 100.0 100.0 100.0 100.0 The correlation between L/B ratio, H 2 evolution, BTX yield, and total paraffins and olefins content across the ZSM-5-based catalysts reveals key structure-function relationships in naphtha aromatization (Fig. 9 ). As the L/B ratio increases from 0.045 (Z5) to 1.95 (2%La-1%Zn/Z5-AT), both BTX and total aromatics yields improve significantly, indicating the crucial role of Lewis acid sites, particularly those introduced by Zn, in promoting dehydrogenation and aromatization. The highest H 2 evolution (9.09 mol%) observed for 1%Zn/Z5-AT confirms the role of Zn in enhancing alkane to olefin and olefin to aromatic pathways. Interestingly, the 2%La-1%Zn/Z5-AT catalyst exhibits the highest BTX yield (72.7 wt.%) but a slightly lower H 2 formation (7.70 mol%), suggesting that La incorporation modulates Zn dispersion and acidity in a way that enhances selectivity without excessive dehydrogenation. Whereas 2%La/Z5-AT exhibits a higher L/B ratio than Z5-AT, its BTX yield is slightly lower. This is likely due to La 3+ neutralizing Brønsted acid sites, reducing the cracking and olefin formation necessary for aromatization. While the Lewis acidity increases, the absence of a dehydrogenation function and diminished Brønsted activity limit the formation of BTX precursors, resulting in lower selectivity. In contrast, the parent Z5, with a low L/B ratio and lacking a dehydrogenation metal, exhibits poor BTX selectivity (24 wt.%) and high retention of paraffins and olefins (53.1 wt.%), highlighting the limitations of Brønsted acidity-dominated systems. Overall, the combined tuning of acid site distribution and metal function provides a synergistic pathway for boosting BTX production while controlling hydrocarbon cracking and gas formation. The conversion of light naphtha involves multiple reaction pathways primarily governed by the carbenium mechanism, which facilitates cracking, isomerization, oligomerization, and cyclization at Brønsted acid sites. In contrast, the Lewis acid sites promote dehydrogenation and/or hydrogen transfer reactions. 48 – 49 During aromatization, the accumulation of larger intermediates on internal acid sites can lead to micropore blockage, causing coke formation and catalyst deactivation. 50 The adequate balance of acid sites significantly enhance the aromatization performance by supporting key steps in the reaction mechanism. Firstly, the alkanes are transformed into olefins by dissociative chemisorption, which are subsequently transformed into aromatics via cyclization and oligomerization on acidic sites. 51 Uniform dispersion of metal species over mesoporous zeolites enhances the aromatization by suppressing excessive cracking to lower olefins. Mesostructured zeolites enhance mass transfer, increase accessibility to acid sites, and facilitate better metal distribution, contributing to higher reaction efficiency. The total aromatics yields by the 1%Zn/Z5-AT and 2%La-1%Zn/Z5-AT catalysts are 70.6 wt.% and 74.4 wt.%, respectively, with a toluene-to-benzene ratio of approximately 0.5 for both catalysts. The high aromatic selectivity is attributed to the dehydrogenation function of Zn, while La plays a role in acidity tuning and diffusion control, enabling conversion of small paraffinic fragments (e.g., C 3 and C 4 ) into aromatics via secondary reactions. In contrast, 2%La/Z5-AT catalysts yielded significantly lower aromatics (47 wt.%), which can be ascribed to limited dehydrogenation activity, increased olefin dimerization, and reduced Brønsted acidity. However, the gaseous olefin and paraffin products C 1 , C 2 , C 2 = , and C 3 + C 4 displayed a slight change with or without the addition of bimetallic species to Z5-AT. 2%La-1%Zn/Z5-AT, methane and ethane yields stabilized at ~ 3.8 wt.% and 5.4 wt.%, respectively, during 1 h TOS, while C 3 + C 4 hydrocarbons remained the dominant fraction (~ 15.2 wt.%) influencing overall gas selectivity. These findings confirm that 2% La-1%Zn/Z5-AT is as an effective catalyst, with performance comparable to recently reported systems for light naphtha conversion, as summarized in Table S2 . The catalytic stability of Z5-AT and 2%La-1%Zn/Z5-AT for light naphtha aromatization was evaluated based on BTX and gaseous products yields, as shown in Figure S3 and Fig. 8 c-d. Both Catalysts maintained consistent conversion levels, with Z5-AT showing commendable stability in BTX production. Notably, the 2%La-1%Zn/Z5-AT catalyst sustained a high BTX yield of 72.7 wt.% over 6 hours on stream, reflecting its robust performance. Catalyst deactivation, particularly in Z5, was primarily attributed to coke accumulation within micropores. The measured coke deposits on the spent catalysts as follows. Z5 (1.61 wt.%), Z5-AT (1.13 wt.%), 1%Zn/Z5-AT (1.58 wt.%), 2%La/Z5-AT (0.55 wt.%), and 2%La-1%Zn/Z5-AT (1.53 wt.%). The significantly reduced coke deposition observed in Z5-AT and 2%La/Z5-AT compared to Z5 confirms the beneficial role of mesoporosity and modified acidity in mitigating carbon buildup. These results indicate that introducing mesoporous architecture enhances catalyst stability by facilitating molecular diffusion and reducing pore blockage. Interestingly, despite moderate coke accumulation, the BTX yield for 2%La–1%Zn/Z5-AT slightly increased with time-on-stream, suggesting that this catalyst resists deactivation and maintains active site accessibility. This study highlights the effectiveness of tailored mesoporous-microporous ZSM-5 structures for long-term naphtha aromatization and presents strategies to overcome limitations associated with microporous catalysts. The findings may also benefit other acid-catalyzed processes constrained by diffusional resistance or rapid deactivation. 4. Conclusions The micropores in the Z5 [Si/Al ratio of 30] structure limit the catalytic conversion of naphtha aromatization due to the diffusion constraints imposed by naphtha bulky feed molecules. To circumvent this, desilication in an alkaline solution resulted in the formation of homogeneous intracrystalline mesopores in Z5, improving molecular transport and enhancing hydrocracking and aromatization activity. The microporous Z5 produces 24 wt.% BTX, while the mesoporous Z5-AT demonstrates a markedly improved yield for aromatics at 49 wt.%. Further incorporation of optimal amounts of La and Zn introduced dehydrogenation functionality, enabling the modified Z5-AT to reach a maximum BTX yield of 72.7 wt.% at 550 °C. The uniform distribution of La and Zn species across the mesoporous matrix improved catalytic performance by boosting dehydrogenation, promoting aromatic ring formation, and suppressing undesired gaseous by-products. The synergistic interaction between zinc and lanthanum, combined with enhanced mesoporosity and a balanced distribution of Brønsted and Lewis acid sites, facilitated both cyclization and dehydrogenation pathways, thus maximizing aromatic selectivity and catalyst efficiency. Declarations ASSOCIATED CONTENT Supporting Information The Supporting Information contains: NH 3 -TPD profiles of parent Z5 material; acid quantities of several zeolite samples as calculated from NH 3 -TPD profiles; EDX spectrum of 2%La-1%Zn/Z5-AT material; stability test results of Z5-AT catalyst samples; liquid yield stability, gas yield stability. Author Information Corresponding Author Ziyauddin S. Qureshi - Interdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia, Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia; https://orcid.org/0000-0002-5033-9016 E-mail: [email protected] Authors Muhammad Waqas - Interdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia , https://orcid.org/0000-0002-4249-3857 Tatinaidu Kella- Interdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia, https://orcid.org/0000-0003-4936-9821 Yaming Jin- Research & Development Center, Saudi Aramco, Dhahran 31311, Saudi Arabia Abdullah M. Aitani- Interdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia, Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia , https://orcid.org/0000-0001-5071-4034 Hassan Alasiri- Interdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia, Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia, https://orcid.org/0000-0003-4043-5677 Notes The authors declare no competing financial interest. Acknowledgments The authors are grateful to Saudi Aramco for funding for project CRP02283. We greatly appreciate the assistance from King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, Saudi Arabia. References Akhtar, M. N.; Aitani, A. M.; Ummer, A. C.; Alasiri, H. S. Review on the Catalytic Conversion of Naphtha to Aromatics: Advances and Outlook. Energy. Fuels. 2023 , 37 , 2586-2607. Song, S., Li, T., Ju, Y., Li, Y., Lv, Z., Zheng, P., ... & Wang, X. Lanthanum/Gallium-modified Zn/ZSM-5 zeolite for efficient isomerization/aromatization of FCC light gasoline. Ind. Eng. Chem. Res. 2022 , 61, 9667-9677. Ummer, A. C., Akhtar, M. N., Alnaimi, E., Ding, L., & Alasiri, H. S. Aromatization of Commercial Full Range Naphtha Over Modified Hierarchical ZSM‐5 Catalyst. ChemistrySelect. 2021 , 6, 11541-11550. llouh, M.; Qureshi, Z. S.; Aitani, A.; Akhtar, M. N.; Jin, Y.; Koseoglu, O.; Alasiri, H. Light paraffinic naphtha to BTX aromatics over metal‐modified Pt/ZSM‐5. ChemistrySelect. 2020 , 5 , 13807-13813. Egolf, B.; Lafyatis, D.; Serban, M.; Lok, K.; Lapinski, M. The Honeywell UOP CCR Platforming™ Process for BTX Production (Case Study). In Industrial Arene Chemistry , 2023 ; pp 269-295. Fung, S. C. Deactivation and Regeneration/Redispersion Chemistry of Pt/KL-Zeolite. In Studies in Surface Science and Catalysis , Spivey, J. J., Roberts, G. W., Davis, B. H. Eds.; Vol. 139; Elsevier, 2001 ; pp 399-406. Rodríguez, M. A.; Ancheyta, J. Detailed description of kinetic and reactor modeling for naphtha catalytic reforming. Fuel. 2011 , 90 , 3492-3508. Hughes, T. R.; Buss, W. C.; Tamm, P. W.; Jacobson, R. L. Aromatization of Hydrocarbons over Platinum Alkaline Earth Zeolites. In Studies in Surface Science and Catalysis , Murakami, Y., Iijima, A., Ward, J. W. Eds.; Vol. 28; Elsevier, 1986 ; pp 725-732. Aitani, A.; Akhtar, M. N.; Al-Khattaf, S.; Jin, Y.; Koseoglo, O.; Klein, M. T. Catalytic Upgrading of Light Naphtha to Gasoline Blending Components: A Mini Review. Energ. Fuels. 2019 , 33 , 3828-3843. Falter, Christoph. Solar Thermochemical Fuels. Conversion of Water and CO 2 to Fuels using Solar Energy: Science, Technology and Materials. 2024 , 47-82. Qureshi, Z. S.; Ellouh, M.; Aitani, A.; Akhtar, M. N.; Jin, Y.; Koseoglu, O.; Alasiri, H. Efficient conversion of light paraffinic naphtha to aromatics over metal-modified Mo/MFI catalysts. J. Porous Mater. 2022 , 29 , 683-692. Wu, Y.; Yang, J.; Wu, G.; Gao, W.; Silva Lora, E. E.; Isa, Y. M.; Subramanian, K. A.; Kozlov, A.; Zhang, S.; Huang, Y. Benzene, toluene, and xylene (BTX) production from catalytic fast pyrolysis of biomass: a review. ACS Sustain. Chem. Eng. 2023 , 11 , 11700-11718. Waqas, M.; Qureshi, Z. S.; Siddiqui, M. A.; Aitani, A.; Akah, A. C. Development of hierarchical ZSM-11 for synthesis of light olefins from crude oil. J. Anal. Appl. Pyrolysis. 2024 , 185, 106870. Shamzhy, M.; Opanasenko, M.; Concepción, P.; Martínez, A. New trends in tailoring active sites in zeolite-based catalysts. Chem. Soc. Rev. 2019 , 48 , 1095-1149. Mole, T.; Anderson, J. R.; Creer, G. The reaction of propane over ZSM-5-H and ZSM-5-Zn zeolite catalysts. Applied catalysis 1985 , 17 , 141-154. Guisnet, M.; Gnep, N. S.; Alario, F. Aromatization of short chain alkanes on zeolite catalysts. Appl. Catal. A: Gen. 1992 , 89 , 1-30. Pan, D.; Song, X.; Yang, X.; Gao, L.; Wei, R.; Zhang, J.; Xiao, G. Efficient and selective conversion of methanol to para-xylene over stable H [Zn, Al] ZSM-5/SiO 2 composite catalyst. Appl. Catal. A: Gen. 2018 , 557 , 15-24. Zhang, J.; Qian, W.; Kong, C.; Wei, F. Increasing para-xylene selectivity in making aromatics from methanol with a surface-modified Zn/P/ZSM-5 catalyst. ACS Catal. 2015 , 5 , 2982-2988. Miyamoto, M.; Mabuchi, K.; Kamada, J.; Hirota, Y.; Oumi, Y.; Nishiyama, N.; Uemiya, S. para-Selectivity of silicalite-1 coated MFI type galloaluminosilicate in aromatization of light alkanes. J. Porous Mater. 2015 , 22 , 769-778. Frey, K.; Lubango, L. M.; Scurrell, M. S.; Guczi, L. Erratum to: Light alkane aromatization over modified Zn-ZSM-5 catalysts: characterization of the catalysts by hydrogen/deuterium isotope exchange. React. Kinet. Mech. Catal. 2011 , 104 , 311. Dong, S.; Ryu, T.; Oi, C.; Wu, J.; Altvater, N. R.; Hagmann, R.; Alikhani, Z.; Lebrón-Rodríguez, E. A.; Jansen, J. H.; Cecon, V. S. Catalytic conversion of post-consumer recycled high-density polyethylene oil over Zn-impregnated ZSM-5 catalysts. Chem. Eng. J. 2024 , 482 , 148889. Ummer, A. C.; Akhtar, M. N.; Alnaimi, E.; Alasiri, H. S.; Ding, L.; Sanhoob, M. A.; Alotaibi, F. Understanding the Promotional Effect of Silver in Naphtha Reforming over a Ga/ZSM-5 Catalyst to Enhance Liquid Yield. The J. Phy. Chem. C. 2024 , 128 , 1971-1981. Anekwe, I. M. S.; Chetty, M.; Khotseng, L.; Kiambi, S. L.; Maharaj, L.; Oboirien, B.; Isa, Y. M. Stability, deactivation and regeneration study of a newly developed HZSM-5 and Ni-doped HZSM-5 zeolite catalysts for ethanol-to-hydrocarbon conversion. Catal. Commun. 2024 , 186 , 106802. Qian, K.; Tian, W.; Yan, S.; Li, W.; Yin, L.; Guo, D.; Yang, Z.; Chen, D.; Feng, Y. Aromatization of HDPE and PP over Ga-promoted zeolite: Effects of pretreatment and zeolite type. Fuel. 2024 , 357 , 129781. Zheng, S.; Heydenrych, H. R.; Jentys, A.; Lercher, J. A. Influence of surface modification on the acid site distribution of HZSM-5. J. Phy. Chem. B. 2002 , 106 , 9552-9558. Hibino, T.; Niwa, M.; Murakami, Y. Shape-selectivity over HZSM-5 modified by chemical vapor deposition of silicon alkoxide. J. Catal. 1991 , 128 , 551-558. Lischke, G.; Eckelt, R.; Jerschkewitz, H. G.; Parlitz, B.; Schreier, E.; Storek, W.; Zibrowius, B.; Öhlmann, G. Spectroscopic and physicochemical characterization of P-modified H-ZSM-5. J. Catal. 1991 , 132 , 229-243. Xue, B.; Zhang, G.; Liu, N.; Xu, J.; Shen, Q.; Li, Y. Highly selective synthesis of para-diethylbenzene by alkylation of ethylbenzene with diethyl carbonate over boron oxide modified HZSM-5. J. Mol. Catal. A Chem. 2014 , 395 , 384-391. Zhang, J.; Zhu, X.; Wang, G.; Wang, P.; Meng, Z.; Li, C. The origin of the activity and selectivity of silicalite-1 zeolite for toluene methylation to para-xylene. Chem. Eng. J. 2017 , 327 , 278-285. Li, J.; Tong, K.; Xi, Z.; Yuan, Y.; Hu, Z.; Zhu, Z. Highly-efficient conversion of methanol to p-xylene over shape-selective Mg–Zn–Si-HZSM-5 catalyst with fine modification of pore-opening and acidic properties. Catal. Sci. Technol. 2016 , 6 , 4802-4813. Groen, J. C.; Moulijn, J. A.; Pérez-Ramírez, J. Alkaline posttreatment of MFI zeolites. From accelerated screening to scale-up. Ind. Eng. Chem. Res. 2007 , 46 , 4193-4201. Zhao, H.; Ma, J.; Zhang, Q.; Liu, Z.; Li, R. Adsorption and diffusion of n-heptane and toluene over mesoporous ZSM-5 zeolites. Ind. Eng. Chem. Res. 2014 , 53 , 13810-13819. Verboekend, D.; Pérez-Ramírez, J. Design of hierarchical zeolite catalysts by desilication. Catal. Sci. Technol. 2011 , 1 , 879-890. Tao, H.; Yang, H.; Liu, X.; Ren, J.; Wang, Y.; Lu, G. Highly stable hierarchical ZSM-5 zeolite with intra-and inter-crystalline porous structures. Chem. Eng J. 2013 , 225 , 686-694. Tarach, K. A.; Martinez-Triguero, J.; Rey, F.; Góra-Marek, K. Hydrothermal stability and catalytic performance of desilicated highly siliceous zeolites ZSM-5. J. Catal. 2016 , 339 , 256-269. Almutairi, S. M. T.; Mezari, B.; Magusin, P. C. M. M.; Pidko, E. A.; Hensen, E. J. M. Structure and reactivity of Zn-modified ZSM-5 zeolites: the importance of clustered cationic Zn complexes. ACS. Catal. 2012 , 2 , 71-83. Vishwanathan, V.; Jun, K.-W.; Kim, J.-W.; Roh, H.-S. Vapour phase dehydration of crude methanol to dimethyl ether over Na-modified H-ZSM-5 catalysts. Appl. Catal. A: Gen. 2004 , 276 , 251-255. Ahn, J. H.; Kolvenbach, R.; Neudeck, C.; Al-Khattaf, S. S.; Jentys, A.; Lercher, J. A. Tailoring mesoscopically structured H-ZSM5 zeolites for toluene methylation. J. Catal. 2014 , 311 , 271-280. Zhou, F.; Gao, Y.; Wu, G.; Ma, F.; Liu, C. Improved catalytic performance and decreased coke formation in post-treated ZSM-5 zeolites for methanol aromatization. Micropor. Mesop Mate. 2017 , 240 , 96-107. Verboekend, D.; Mitchell, S.; Milina, M.; Groen, J. C.; Pérez-Ramírez, J. Full compositional flexibility in the preparation of mesoporous MFI zeolites by desilication. J. Phys Chem. C. 2011 , 115 , 14193-14203. Su, X.; Zan, W.; Bai, X.; Wang, G.; Wu, W. Synthesis of microscale and nanoscale ZSM-5 zeolites: effect of particle size and acidity of Zn modified ZSM-5 zeolites on aromatization performance. Catal. Sci. Technol. 2017 , 7 , 1943-1952. Long, X.; Zhang, Q.; Liu, Z.-T.; Qi, P.; Lu, J.; Liu, Z.-W. Magnesia modified H-ZSM-5 as an efficient acidic catalyst for steam reforming of dimethyl ether. Appl. Catal. B: Environ. 2013 , 134 , 381-388. Song, Z.; Takahashi, A.; Nakamura, I.; Fujitani, T. Phosphorus-modified ZSM-5 for conversion of ethanol to propylene. Appl. Catal. A: Gen. 2010 , 384 , 201-205. Niu, X.; Gao, J.; Wang, K.; Miao, Q.; Dong, M.; Wang, G.; Fan, W.; Qin, Z.; Wang, J. Influence of crystal size on the catalytic performance of H-ZSM-5 and Zn/H-ZSM-5 in the conversion of methanol to aromatics. Fuel Process. Technol. 2017 , 157 , 99-107. Berndt, H.; Lietz, G.; Völter, J. Zinc promoted H-ZSM-5 catalysts for conversion of propane to aromatics II. Nature of the active sites and their activation. Appl. Catal. A: Gen. 1996 , 146 , 365-379. Li, F.; Ding, S.; Wang, Z.; Li, Z.; Li, L.; Gao, C.; Zhong, Z.; Lin, H.; Chen, C. Production of light olefins from catalytic cracking bio-oil model compounds over La2O3-modified ZSM-5 zeolite. Energ. fuels. 2018 , 32 , 5910-5922. Sang, Y.; Li, H. Effect of phosphorus and mesopore modification on the HZSM-5 zeolites for n-decane cracking. J. Solid State Chem. 2019 , 271 , 326-333. Ono, Y. Transformation of lower alkanes into aromatic hydrocarbons over ZSM-5 zeolites. Catalysis Reviews 1992 , 34 , 179-226. MÉRiaudeau, P.; Naccache, C. Dehydrocyclization of alkanes over zeolite-supported metal catalysts: monofunctional or bifunctional route. Catal. Rev. 1997 , 39 , 5-48. Lee, K.; Lee, S.; Jun, Y.; Choi, M. Cooperative effects of zeolite mesoporosity and defect sites on the amount and location of coke formation and its consequence in deactivation. J. Catal. 2017 , 347 , 222-230. Su, X.; Fang, Y.; Bai, X.; Wu, W. Synergic effect of GaO+/Brønsted acid in hierarchical Ga/Al-ZSM-5 bifunctional catalysts for 1-hexene aromatization. Ind. Eng. Chem. Res. 2019 , 58 , 20543-20552. Additional Declarations No competing interests reported. Supplementary Files Supplementaryinformation.docx GraphicalAbstract.docx Cite Share Download PDF Status: Published Journal Publication published 05 Dec, 2025 Read the published version in Journal of Porous Materials → Version 1 posted Editorial decision: Revision requested 14 Sep, 2025 Reviews received at journal 10 Sep, 2025 Reviewers agreed at journal 26 Aug, 2025 Reviewers agreed at journal 26 Aug, 2025 Reviewers agreed at journal 26 Aug, 2025 Reviewers agreed at journal 26 Aug, 2025 Reviewers invited by journal 26 Aug, 2025 Editor assigned by journal 20 Aug, 2025 Submission checks completed at journal 20 Aug, 2025 First submitted to journal 19 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Qureshi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA70lEQVRIie3NMWrDMBTG8ScEmp7j1UahvoKDwEsCvYqKVy+mB0gg4CwunXWLQsFzQJAuDlkN7ZAsmTLYWwYNtUuh0IBItgz6L+8tPz4Al+t+W6OPZP/7X0vCksa3EYjra0m0ypK2NV9jUWvG8wweRo2k7dlCSHkSShVHTLZLxlUFImwkC0sLoUEmqLfQmOz8DfcqeHrrCaCFsIEYo1G8UjaQeU9oZywEBwJMY+wtf4iMGwncthLg8Zm8FBqDWtOpqoKJqg8FH1tItErf4Wz0o1+m5DOvZtHoI9XdyUIA5N9L+9X+kIUV/Ccul8vluuwb4o5JSGsSzq0AAAAASUVORK5CYII=","orcid":"","institution":"King Fahd University of Petroleum \u0026 Minerals","correspondingAuthor":true,"prefix":"","firstName":"Ziyauddin","middleName":"S.","lastName":"Qureshi","suffix":""},{"id":507175776,"identity":"be48e514-54e6-48e0-9d00-6ad887ab9de1","order_by":3,"name":"Yaming Jin","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yaming","middleName":"","lastName":"Jin","suffix":""},{"id":507175777,"identity":"a8f31eb6-8988-428f-8bd9-b008db235eda","order_by":4,"name":"Abdullah Aitani","email":"","orcid":"","institution":"King Fahd University of Petroleum \u0026 Minerals","correspondingAuthor":false,"prefix":"","firstName":"Abdullah","middleName":"","lastName":"Aitani","suffix":""},{"id":507175778,"identity":"f814225d-5d79-4812-b8bb-6775d8c29cec","order_by":5,"name":"Hassan Alasiri","email":"","orcid":"","institution":"King Fahd University of Petroleum \u0026 Minerals","correspondingAuthor":false,"prefix":"","firstName":"Hassan","middleName":"","lastName":"Alasiri","suffix":""}],"badges":[],"createdAt":"2025-08-19 11:53:24","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7408317/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7408317/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10934-025-01879-7","type":"published","date":"2025-12-05T15:57:59+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":90488476,"identity":"7e911f86-b1eb-4ac6-938c-c4db23cd601f","added_by":"auto","created_at":"2025-09-03 09:13:02","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":46257,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic illustration of mesostructured metal-modified catalysts developed from Z5 (ZSM-5).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/ea50c5433224d12e9b4c9f4f.png"},{"id":90488477,"identity":"3e06c9f4-364b-4889-b058-e8e0f3e400c3","added_by":"auto","created_at":"2025-09-03 09:13:02","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":37619,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of the fixed-bed downflow reactor system.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/82a008a4124b7ecc9a5a50dc.png"},{"id":90488858,"identity":"5d28439e-c4ee-4cdd-a891-e34943fc8ca3","added_by":"auto","created_at":"2025-09-03 09:21:03","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":164138,"visible":true,"origin":"","legend":"\u003cp\u003eX-ray diffraction patterns and relative crystallinity of parent and modified ZSM-5 catalysts.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/ce5920d7a4cbf9645eb24e39.png"},{"id":90490171,"identity":"f9f88031-716e-4752-9754-d43a5100014d","added_by":"auto","created_at":"2025-09-03 09:29:03","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":214877,"visible":true,"origin":"","legend":"\u003cp\u003eParent and metal-modified ZSM-5 N\u003csub\u003e2\u003c/sub\u003e adsorption-desorption isotherms.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/830da05e5610d6b3ad45acc9.png"},{"id":90488479,"identity":"d2bb98aa-af92-4239-94d7-a3c91c3c0a5e","added_by":"auto","created_at":"2025-09-03 09:13:02","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":132558,"visible":true,"origin":"","legend":"\u003cp\u003eNH\u003csub\u003e3\u003c/sub\u003e-TPD profiles of (a) Z5-AT, (b) 1%Zn/Z5-AT, (c) 2%La-Z5-AT, and (d) 2%La-1%Zn/Z5-AT.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/53f2aeba018e34181b24cd5a.png"},{"id":90488855,"identity":"9a803fa2-3ac4-4375-a6aa-d27007437f12","added_by":"auto","created_at":"2025-09-03 09:21:03","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":177948,"visible":true,"origin":"","legend":"\u003cp\u003eFTIR spectra of adsorbed pyridine on Zn and La-containing alkali-treated zeolite samples; (a) Z5-AT, (b) 1%Zn/Z5-AT, (c) 2%La/Z5-AT, (d) 2%La-1%Zn/Z5-AT. Pyridine interacts with Brønsted and Lewis acid sites to produce the absorption bands named as BAS and LAS, respectively\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/8d1d1f1cf9f23dec2f2785c4.png"},{"id":90488512,"identity":"ec04d1fa-68a1-4c39-96c2-a4d8f6d12493","added_by":"auto","created_at":"2025-09-03 09:13:03","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":449630,"visible":true,"origin":"","legend":"\u003cp\u003e(a and d) the SEM and TEM images of parent Z5, (b and e) Z5-AT, (c and f) 2%La-1%Zn/Z5-AT, and (g) SEM-EDX mapping of 2%La-1%Zn/Z5-AT.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/a20c6c097baa3101d0d25ddc.png"},{"id":90490173,"identity":"c1624476-1afd-481d-9729-8dc77e1c9230","added_by":"auto","created_at":"2025-09-03 09:29:03","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":178357,"visible":true,"origin":"","legend":"\u003cp\u003eProduct distribution and stability in light naphtha aromatization at 550 °C and 1.0 h\u003csup\u003e-1\u003c/sup\u003e WHSV. (a, b) Liquid and gas yields over parent and modified catalysts; (c, d) Liquid and gas yield stability of 2%La-1%Zn/Z5-AT.\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/d01b5413d2b55aa6997f051d.png"},{"id":90488498,"identity":"a533675b-42a8-44c4-9ebc-cabe5d0b62d7","added_by":"auto","created_at":"2025-09-03 09:13:03","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":103050,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of L/B ratio on H\u003csub\u003e2\u003c/sub\u003e evolution, BTX formation, and gaseous hydrocarbon yields over parent and modified ZSM-5 catalysts in light naphtha aromatization.\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/b59076753e32a77f4fef10e2.png"},{"id":97723901,"identity":"dd6c1348-8352-4272-bd63-afd9c1e072c0","added_by":"auto","created_at":"2025-12-08 16:09:28","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2567801,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/309b0590-59c2-4bdf-a5f1-2e7b463f8611.pdf"},{"id":90488484,"identity":"5cabd391-2374-438e-8073-6cfb78e1166c","added_by":"auto","created_at":"2025-09-03 09:13:03","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":270299,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementaryinformation.docx","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/3ec01b8e90fd2e770584a2e1.docx"},{"id":90488486,"identity":"11396bb4-f7de-496b-adce-ec85bd4debc9","added_by":"auto","created_at":"2025-09-03 09:13:03","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":1148043,"visible":true,"origin":"","legend":"","description":"","filename":"GraphicalAbstract.docx","url":"https://assets-eu.researchsquare.com/files/rs-7408317/v1/83027fcecd0bf35729893ba7.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Mesostructured Bimetallic MFI Zeolite for Efficient Aromatization of Light Naphtha to BTX Aromatics","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eBTX aromatics (benzene, toluene, and xylenes) are fundamental petrochemical intermediates widely used in the production of high-value materials, including plastics, organic solvents, and fuel additives.\u003csup\u003e\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e The oil refining industry has consistently strived to enhance the output of highly valued BTX through catalytic light naphtha reforming.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e Conventional catalytic reforming, primarily designed for heavy naphtha (C\u003csub\u003e7\u003c/sub\u003e-C\u003csub\u003e9\u003c/sub\u003e), is efficient in converting naphthenes and paraffins to aromatics. However, its effectiveness diminishes significantly when processing light naphtha (C\u003csub\u003e5\u003c/sub\u003e-C\u003csub\u003e6\u003c/sub\u003e) due to its low aromatic precursors and high paraffin content. Moreover, the process often results in the generation of low-value heavy aromatics (C\u003csub\u003e9+\u003c/sub\u003e), which limits the selectivity toward BTX.\u003csup\u003e\u003cspan additionalcitationids=\"CR7\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e In the chemical industry, ~ 60% light naphtha (C\u003csub\u003e5\u003c/sub\u003e-C\u003csub\u003e6\u003c/sub\u003e) is diverted to steam cracking units for olefin production (primarily ethylene), while around 30% is isomerized and blended into gasoline to meet octane requirements.\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e Therefore, the availability, consumption, and costs of naphtha have a substantial impact on profitability in the petrochemical and refining industries.\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e Light naphtha's limited usage in direct blending is also constrained by its high Reid Vapor Pressure (RVP) and low octane number, which can negatively impact gasoline volatility specifications.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e As a result, its upgrading to more valuable chemical intermediates is gaining interest.\u003c/p\u003e\u003cp\u003eGlobally, the daily light naphtha demand is estimated at 8.8\u0026nbsp;million barrels, while gasoline consumption reaches approximately 26.1\u0026nbsp;million barrels per day, representing more than 26% of the world's total refined product market.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e These figures underline the strategic importance of naphtha utilization efficiency in determining refinery profitability. Given the rising demand for para-xylene and benzene, particularly in the production of polyethylene terephthalate (PET), there is growing industrial and academic interest in catalytic routes for converting light naphtha into BTX aromatics. The global BTX market was valued at USD 6.73\u0026nbsp;billion in 2022 and is projected to grow at a CAGR of 5.22%, reaching USD 9.13\u0026nbsp;billion by 2028.\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eSeveral types of zeolites, such as mordenite, beta zeolite, ZSM-5, ZSM-11, and zeolite Y are widely recognized as efficient catalysts for transforming light naphtha into aromatic compounds.\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e,\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e Among them, ZSM-5 is particularly favored due to its high surface area, thermal stability, and well-defined microporous structure.\u003csup\u003e\u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e ZSM-5 that have been combined with various oxides are acknowledged as an effective material for improving aromatization selectivity.\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e The optimal aluminum content in the ZSM-5 framework enhances its acidity, thereby promoting cracking, while the metal functionality supports dehydrogenation, facilitating the conversion of olefins into aromatics.\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e Much effort has been devoted to achieving higher aromatization selectivity by utilizing various metal incorporation in the framework of ZSM-5, for instance, Zn,\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e Ag,\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e Ni,\u003csup\u003e\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u003c/sup\u003e Ga,\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e etc. Zinc, in particular, is considered highly effective due to its abundance, low toxicity, and strong aromatization performance. Adding other oxides of elements such as Si,\u003csup\u003e\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e P,\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e, and B\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e helps to selectively passivate the external acid sites of ZSM-5, thereby shielding the BTX molecules that have generated inside the interior micropores from secondary isomerization. Additionally, by obstructing pore openings, it slightly increases the micropore channels' shape selectivity.\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e,\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e Metal-modified ZSM-5 zeolites can effectively convert light naphtha to BTX, offering enhanced selectivity and improved aromatization activity. Although surface modification of ZSM-5 with additional oxides enhances BTX selectivity, excessive blocking of pore openings can hinder aromatic diffusion and reduce overall catalytic efficiency and stability.\u003csup\u003e\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e Increasing acid site availability enhances overall aromatization activity, while incorporating mesopores can mitigate carbon deposition. Designing mesostructured ZSM-5 catalysts with multiple oxide modifiers offers a promising strategy to balance the trade-off between shape-selectivity and catalytic activity. Desilication under alkaline conditions is one of the methods used to fabricate mesoporous zeolites, or the mesopores can also be created by utilizing templates and subsequent treatment protocols.\u003csup\u003e\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThis study examines the diffusion limitations of bulky hydrocarbons in the micropore channels of ZSM-5 zeolite by generating homogeneous intracrystalline mesopore channels through a straightforward and efficient alkaline desilication post-treatment for catalytic upgrading of light naphtha into BTX aromatics. BET and TEM analyses confirmed mesopore formation, which facilitated improved molecular transport and enhanced diffusion of BTX aromatics during catalytic conversion of light naphtha. XRD, TEM, and SEM-EDX analyses demonstrate the uniform dispersion of zinc and lanthanum sites on mesopore ZSM-5. We used NH\u003csub\u003e3\u003c/sub\u003e-TPD and pyridine FT-IR to analyze the Lewis and Br\u0026oslash;nsted acidic sites and reduction characteristics of the prepared catalysts. The characterization outcomes were comprehensively analyzed, with an effort to establish correlations between physicochemical properties of the catalysts and catalytic performance in light naphtha aromatization.\u003c/p\u003e"},{"header":"2. EXPERIMENTAL SECTION","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1. Materials\u003c/h2\u003e\u003cp\u003eZSM-5 zeolite powder CBV 3024E with a SiO\u003csub\u003e2\u003c/sub\u003e/Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e molar ratio of 30 was procured from Zeolyst. The choice of ZSM-5 zeolite with a SiO\u003csub\u003e2\u003c/sub\u003e/Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e ratio of 30 is based on its recognition as a benchmark for regulated post-synthesis modifications aimed at achieving mesoporosity. A hydrotreated light-straight run (LSR) naphtha sample was obtained from a local refinery processing a crude oil comprising 25% Arab Light and 75% Arab Heavy. The value of sulfur in LSR naphtha was 43 parts per million (ppm), while its density was 0.676 g/cm\u003csup\u003e3\u003c/sup\u003e. A comprehensive hydrocarbon analyzer (Shimadzu GC-DHA) was employed to examine the concentrations of \u003cem\u003eiso\u003c/em\u003e-paraffins, \u003cem\u003en\u003c/em\u003e-paraffins, olefins, aromatics, and naphthenes in LSR naphtha. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e presents the components of naphtha feed with 90 wt.% paraffins.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComposition of light straight run naphtha feed.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComponent, wt.%\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003en\u003c/em\u003e-Paraffins\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eiso\u003c/em\u003e-Paraffins\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eNaphthenes\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eAromatics\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e5\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e25.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e36.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e6\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e25.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e26.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e5.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e58.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e7\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e4.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e51.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e38.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e8.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e100\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2. Preparation of desilicated Z5-AT zeolite\u003c/h2\u003e\u003cp\u003eThe NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-form ZSM-5 zeolite was calcined in static air at 550\u0026deg;C for 5 h (heating rate: 5\u0026deg;C/min) to obtain the protonic form, designated as Z5. Alkaline desilication was performed using 0.2 M NaOH solution at a zeolite-to-solution ratio of 1 g:10 mL. The solution was stirred at 500 rpm and preheated to 80 \u003csup\u003eo\u003c/sup\u003eC prior to the addition of the zeolite. The solution was agitated for 60 minutes, then quenched, filtered, and thoroughly rinsed with distilled water until achieving neutral pH, followed by drying for 12 h at 100\u0026deg;C. The desilicated specimen underwent ion exchanges three consecutive times in aqueous NH\u003csub\u003e4\u003c/sub\u003eNO\u003csub\u003e3\u003c/sub\u003e of 1.0 M at a temperature of 80 \u003csup\u003eo\u003c/sup\u003eC for 4.5 hours. Subsequently, the process involved filtration, meticulous washing with distilled water, overnight drying at 100 \u003csup\u003eo\u003c/sup\u003eC, and calcining for 5 h at 550\u0026deg;C, which was labeled as Z5-AT.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3 Preparation of metal-modified Z5-AT catalysts\u003c/h2\u003e\u003cp\u003eZinc- and lanthanum-modified mesoporous ZSM-5 catalysts were synthesized using wet impregnation and co-impregnation techniques, respectively. For single-metal catalysts, aqueous solutions of Zn (NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO or La (NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO were individually impregnated onto the alkali-treated Z5-AT support. In the bimetallic system, both metal precursors were simultaneously added to the support using a co-impregnation approach. The metal precursor(s) were dissolved in 100 mL of deionized water and mixed with Z5-AT in a 250 mL round-bottom flask. The mixture was stirred at 500 rpm for 3 h, followed by slow evaporation at 50\u0026deg;C. The dried solid material was then calcined at 550\u0026deg;C for 5 h. The resulting catalysts were designated as 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La\u0026ndash;1%Zn/Z5-AT.\u003c/p\u003e\u003cp\u003eThe construction of mesopore channels on zeolite surface was achieved through a straightforward and effective alkaline treatment (desilication) strategy (Z5-AT). This was subsequently followed by Zn modification (1%Zn/Z5-AT), La modification (2%La/Z5-AT), and co-modification (2%La-1%Zn-Z5-AT), as depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003e2.4. Catalyst Characterization.\u003c/h2\u003e\u003cp\u003eA series of parent Z5, as-synthesized alkaline Z5-AT, and metal-modified catalysts, such as 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT catalysts were characterized to study their physicochemical and surface properties. The Rigaku Miniflex II utilizes the radiation sourced from Cu K\u0026plusmn;, having a wavelength of 1.5405 \u0026Aring;, under the circumstances of 15 mA, 30 kV, 2\u0026deg; min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e scanning rate, 0.02\u0026deg; from 5\u0026deg; to 50\u0026deg; 2θ is utilized to obtain the XRD patterns of powder samples.\u003c/p\u003e\u003cp\u003eThe BET equation is utilized to measure the pore volume, or pore diameter, surface area, utilizing an ASAP-2020 Micromeritics analyzer and nitrogen adsorption at -195\u0026deg;C. SEM images were captured with a FESEM (Tescan Lyra-3). A 20-kV scanning electron microscope was used. EDXS analysis using LINK INCA software was used to analyze the catalyst elemental composition. Conductive copper tape concealed the specimens on a sample holder. A Cressington ion-coater with 15 mA current coats for 30 seconds in vacuum.\u003c/p\u003e\u003cp\u003eThe NH\u003csub\u003e3\u003c/sub\u003e-TPD testing on a Belcat-A-200 chemisorption instrument was used to measure the acidity of as-prepared catalysts. The system consists of a quartz microreactor, a thermal conductivity detector, and a gas mixing facility. All of the samples had been pre-treated with 50 mL/min of helium at 500\u0026deg;C for 2h. The catalyst was allowed to cool to room temperature and then fed 50 mL/min of ammonia (5% ammonia in helium) for 30 min at 100\u0026deg;C to saturate the acid sites. The surplus ammonia was eliminated at 100\u0026deg;C using a 50 mL/min helium stream for 30 minutes. Chemically adsorbed ammonia was removed by heating at 100\u0026deg;C to 600\u0026deg;C with a ramp rate of 10\u0026deg;C/min. A thermal conductivity detector was used to detect the released ammonia concentration.\u003c/p\u003e\u003cp\u003eWe used the EMIA-220V Horiba Carbon-Sulfur Analyzer to determine the amount of coke present in the spent catalyst. The furnace combusted approximately 10\u0026ndash;20 mg of catalyst, incorporating tungsten as a combustion promoter, at elevated temperatures. We quantified the generated CO\u003csub\u003e2\u003c/sub\u003e using an infrared analyzer and represented it as a weight catalyst percentage.\u003c/p\u003e\u003cp\u003eWe evaluated acid site types using a pyridine adsorption FTIR method with a Scientific Fisher-Nicolet iS10 FTIR spectrometer. In each instance, we used a 120 mg powder sample and compressed it into a thin self-supported disc to place it in a quartz IR cell. We performed evacuation prior to the pyridine adsorption step and recorded the IR spectrum at temperatures of 150\u0026deg;C, 200\u0026deg;C, 250\u0026deg;C, and 300\u0026deg;C to use these spectra as background references. We evacuated the catalyst sample at 500\u0026deg;C for 30 minutes, then cooled it to 150\u0026deg;C. Next, we exposed the sample to pyridine vapor for 5 minutes, then evacuated it under high vacuum for 3 minutes to remove any physisorbed pyridine, and finally recorded IR spectra at 150\u0026deg;C. After recording, we increased the sample temperature to 200\u0026deg;C and obtained spectra. We repeated this process at 250\u0026deg;C and 300\u0026deg;C, ensuring consecutive evacuations at each temperature. We utilized the FTIR spectra obtained at each temperature after pyridine adsorption and evacuation to assess Br\u0026oslash;nsted and Lewis acid sites. Peaks at 1540 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1450 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e correspond to pyridine adsorption on Br\u0026oslash;nsted and Lewis acid sites, respectively. Both Lewis and Br\u0026oslash;nsted sites contribute to the peak at the 1490 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e band, which we exclude from our calculations. Eq.\u0026nbsp;1 calculates the quantitative acidity (C, millimoles of acid sites per gram of the sample).\u003c/p\u003e\u003cp\u003e\u0026#119862;(mmol/g) = (\u0026#119860;\u0026times;\u0026#119878;)/(\u0026#119864;\u0026times;\u0026#119882;) Eq.\u0026nbsp;(1)\u003c/p\u003e\u003cp\u003eA (cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) denotes the area of the IR band, S (cm\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e) represents the pellet area, W (mg) indicates the pellet weight, and E (cm m\u0026micro;\u003csup\u003e\u0026minus;1\u003c/sup\u003e) refers to the extinction coefficients, with values of 1.28 for Lewis sites and 1.13 for Br\u0026oslash;nsted sites.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003e2.5. Catalyst Evaluation\u003c/h2\u003e\u003cp\u003eThe catalyst performance of LSR naphtha aromatization was assessed in a fixed-bed continuous flow reactor (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The reactor comprised a 316 stainless steel tube (203 mm length, 7.9 mm i.d., 3.2 mm wall thickness), packed with 0.5 g of sieved catalyst (500\u0026ndash;1000 \u0026micro;m), supported between layers of silicon carbide and separated by glass wool (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Prior to reaction, the catalyst was pretreated at 550\u0026deg;C for 2h under 20 mL/min N\u003csub\u003e2\u003c/sub\u003e flow, following ASTM D4463 guidelines.\u003c/p\u003e\u003cp\u003eThe reactions were conducted at 550\u0026deg;C under atmospheric pressure, a WHSV of 1.0 h\u003csup\u003e\u0026minus;\u0026thinsp;1,\u003c/sup\u003e and a time-on-stream (TOS) of 1\u0026ndash;6 h. Hydrotreated LSR naphtha was fed at 0.01\u0026ndash;0.5 mL/min, and nitrogen was co-fed at 10 mL/min to maintain flow. The feed and reactor lines were enclosed in an oven maintained at 200\u0026deg;C to ensure complete vaporization. Reaction products were separated via a gas-liquid separator (-10\u0026deg;C), non-condensable gases were analyzed online using a four-channel Agilent Micro-GC (ASTM D7833) to quantify H\u003csub\u003e2\u003c/sub\u003e, N\u003csub\u003e2\u003c/sub\u003e, and C\u003csub\u003e1\u003c/sub\u003e-C\u003csub\u003e6\u003c/sub\u003e hydrocarbons. Liquid samples were collected hourly, weighed, and analyzed using an offline DHA-GC (PIONA column) in accordance with ASTM D6729.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eSystematically monitored the reaction mass balance during all catalytic tests. The calculations are based on the approximate mass of the feed and products, which encompass both liquid and non-condensable gases. Conversion was calculated based on the difference in non-aromatic hydrocarbons between feed and products. Aromatic selectivity was defined as the mass ratio of BTX to total products (normalized to 100%), and liquid yield as the mass of liquid products per mass of naphtha fed over the reaction period.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eOperating parameters of the fixed-bed flow reactor system.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParameter\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eValue\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eReactor temperature, \u0026deg;C\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e550\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCatalyst weight in grams, sieved to 500\u0026ndash;1000 \u0026micro;m particle size\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTime on stream, h\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u0026ndash;6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNitrogen flowrate, mL/min\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePressure\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAtmospheric\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFeed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eLight naphtha\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLight naphtha flowrate, mL/min\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWeight hour space velocity, h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eReactor length/ID, inch\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e8/0.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Results and Discussion","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\u003ch2\u003e3.1. Structural and Textural Properties.\u003c/h2\u003e\u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e presents the XRD patterns of all zeolite-based catalysts. All catalysts' diffraction patterns displayed the typical feature of the MFI structure. Additionally, no diffraction peaks corresponding to La or Zn oxide phases were observed, indicating that La and Zn species are uniformly and well-dispersed on Z5. The alkali modified Z5 sample, after desilication, showed a slight decrease in relative crystallinity of 0.4% in comparison to ZSM-5 parent zeolite. This suggests that the desilication process adopted has a minor impact on the integrity of the zeolite framework.\u003csup\u003e\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e\u003c/sup\u003e The catalyst relative crystallinity decreases with the impregnation of metal(s). The relative crystallinity of bimetallic sample 2%La-1%Zn/Z5-AT decreased significantly to 36%, which can be attributed to the lattice effects caused by the deposition of metal oxide on the surface of zeolite.\u003csup\u003e\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e During the alkaline treatment, partial extraction of Si and some Al from the zeolite structure framework led to Al enrichment on the external surface. As a result, aluminum atoms aggregate on the surface of zeolite, obstructing the small pores and diminishing the crystallinity of ZSM-5.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\u003ch2\u003e3.2. Pore Structure and Surface Properties.\u003c/h2\u003e\u003cp\u003eFigure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e shows the N\u003csub\u003e2\u003c/sub\u003e adsorption-desorption isotherms and pore-size distributions of parent and as-synthesized zeolite catalysts. Compared to microporous pristine Z5, all desilicated samples (Z5-AT, 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT) exhibited increased N\u003csub\u003e2\u003c/sub\u003e uptake in the relative pressure (p/p\u003csup\u003e0\u003c/sup\u003e) range of 0.4\u0026ndash;0.8, confirming the effective creation of mesopores via the desilication method. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, the mesopores for alkali modified Z5-AT sample are centered at about 5\u0026ndash;10 nm. Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e lists the specific textural features of all as-synthesized catalysts. Alkali modified Z5-AT sample has a specific surface area of 343 m\u003csup\u003e2\u003c/sup\u003e/g. Compared to the parent Z5, the desilicated Z5-AT exhibited relatively high specific surface areas and mesopore volumes. The BJH pore size distribution confirmed the presence of intracrystalline mesopores with a medium diameter of 6.3 nm in Z5-AT. A significant increase in the V\u003csub\u003emeso\u003c/sub\u003e/V\u003csub\u003emicro\u003c/sub\u003e ratio was observed after the impregnation of metal(s). Specifically, 1%Zn/Z5-AT and 2%La-1%Zn/Z5-AT achieved values of approximately 2, compared to 1.92 for the Z5-AT. The interaction of NO\u003csub\u003e3\u003c/sub\u003e and NH\u003csub\u003e3\u003c/sub\u003e during the nitride impregnation followed by calcination primarily facilitates desilication, which accounts for the mesoporosity.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e The observed mesoporous characteristics could contribute to their efficacy in light naphtha aromatization.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eTextural characteristics of prepared catalysts.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eProperty\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZ5\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eZ5-AT\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1%Zn/Z5-AT\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2%La/Z5-AT\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2%La-1%Zn/Z5-AT\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSurface area\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBET surface area (m\u003csup\u003e2\u003c/sup\u003e/g)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e342\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e343\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e310\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e307\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e297\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003et\u003c/em\u003e-Plot micropore area (m\u003csup\u003e2\u003c/sup\u003e/g)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e210\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e208\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e194\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e199\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e190\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003et\u003c/em\u003e-Plot external surface area (m\u003csup\u003e2\u003c/sup\u003e/g)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e132\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e135\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e116\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e108\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e107\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePore volume\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTotal pore volume (cm\u003csup\u003e3\u003c/sup\u003e/g)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.278\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.324\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.308\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.286\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.303\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003et\u003c/em\u003e-Plot micropore volume (cm\u003csup\u003e3\u003c/sup\u003e/g) V\u003csub\u003emicro\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.112\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.111\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.103\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.106\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.101\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMesopore volume (cm\u003csup\u003e3\u003c/sup\u003e/g) V\u003csub\u003emeso\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.166\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.213\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.205\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.187\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.202\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eV\u003csub\u003emeso\u003c/sub\u003e/V\u003csub\u003emicro\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.92\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.99\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAverage pore diameter (nm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7.10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6.67\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e7.44\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e3.3. Acidity Measurements.\u003c/h2\u003e\u003cp\u003eThe acidity of parent Z5 and modified catalysts (Z5-AT, 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT) was assessed using NH\u003csub\u003e3\u003c/sub\u003e-TPD analysis. The ammonia desorption is separated using Gaussian peak deconvolution and fitted into three clear peaks. The acid sites can be classified as weak, medium, or strong.\u003csup\u003e\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e,\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u003c/sup\u003e The profiles of NH\u003csub\u003e3\u003c/sub\u003e-TPD profiles, as shown in \u003cb\u003eTable \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e\u003c/b\u003e, determine the quantities of each type of acid site. Desilication seems to slightly reduce the acidity of Z5-AT compared to the parent Z5 (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea \u003cb\u003eand Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e\u003c/b\u003e).\u003c/p\u003e\u003cp\u003ePrevious findings\u003csup\u003e\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u003c/sup\u003e, suggest that desilication under alkaline conditions resulted in the leaching of silicon atoms, leading to the extraction of aluminum atoms. The Al atoms clustered and gathered on the exterior surface, obstructing the micro- and mesopores as Lewis acid sites.\u003csup\u003e\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e,\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e\u003c/sup\u003e When 1%Zn or 2%La species are introduced, the overall acid strength of Z5-AT drops, particularly affecting the strong-acid sites,\u003csup\u003e\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e\u003c/sup\u003e whereas the concentration of medium strong-acid sites somewhat increases (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eb and \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ec). The addition of 2% La and 1% Zn to Z5-AT significantly enhances the overall acidity. This effect contributes to a notable shift of strong acid sites into medium-strong sites, likely as the result of the presence of the abundant Br\u0026oslash;nsted acid sites in the La-Zn/ZSM-5 sample (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ed).\u003csup\u003e\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eFigure \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e depicts the Py-FTIR spectra of all materials at four distinct temperatures from 150 \u003csup\u003eo\u003c/sup\u003eC to 300 \u003csup\u003eo\u003c/sup\u003eC, which were acquired to better assess the acidity of zeolite after desilication and metal modification. Figures\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ea and \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eb illustrate that the introduction of Zn species significantly reduces the quantity of Br\u0026oslash;nsted acid sites, concurrently enhancing the concentration of Lewis acid sites, as evidenced by a notable blue shift. These results suggest that during the Zn modification process, Zn species interact with ZSM-5 Br\u0026oslash;nsted acid sites to produce additional Lewis acid sites. \u003csup\u003e\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e\u003c/sup\u003e According to reports, the impregnated Zn species exist as [ZnOH]\u003csup\u003e+\u003c/sup\u003e ions \u003csup\u003e\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e\u003c/sup\u003e or [ZnOZn]\u003csup\u003e2+\u003c/sup\u003e ions,\u003csup\u003e41\u003c/sup\u003e that enable the conversion of Br\u0026oslash;nsted acid sites to Lewis acid sites. Following additional loading of La species, we observe a decrease in both Br\u0026oslash;nsted and Lewis acid site quantities in Figs.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ec and \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ed. This is because the acid centers are covered by the impregnation of Zn and La oxides.\u003csup\u003e\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e\u003c/sup\u003e Desilication in alkaline environments minimally influences the acidity of zeolites when compared with the modification process, particularly for the ratio of Br\u0026oslash;nsted to Lewis acid sites.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003e3.4. Morphology Analysis.\u003c/h2\u003e\u003cp\u003eScanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the surface, shape, and size distribution of mesopores in zeolite-based materials. In Figs.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003ea and \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003ed, the images obtained from SEM and TEM Z5 display that Z5 has a hexagonal crystal structure with homogeneous micropores, characteristic of ZSM-5 zeolite.\u003csup\u003e\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e,\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e\u003c/sup\u003e In Figs.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eb and \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003ee, the SEM-TEM images of Z5-AT revealed a distinctive hybrid structure containing crystals in spherical and hexagonal shapes, representing a distinct morphology. Moreover, micropores and mesopores are clearly visible throughout the material. The observations corroborate the N\u003csub\u003e2\u003c/sub\u003e adsorption-desorption data, indicating that the desilication process had a substantial effect on the pore structure. The TEM image in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003ef for 2%La-1%Zn/Z5-AT shows dark spots, demonstrating a uniform distribution of La and Zn species across the zeolite framework. In addition, the SAED pattern showed an amorphous nature of the material (inset bottom), which further confirms that La and Zn are well dispersed over the zeolite framework. Figure\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eg \u003cb\u003eand Figure S2\u003c/b\u003e present the elemental mapping data, and the EDX spectrum verifies the existence of silicon (Si), aluminum (Al), oxygen (O), lanthanum (La), and zinc (Zn) in the synthesized catalyst. Additionally, it also confirms the uniform dispersion of La and Zn inside the zeolite structure.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003e3.6. Catalytic Aromatization of Light Naphtha.\u003c/h2\u003e\u003cp\u003eLight naphtha aromatization was carried out in a fixed-bed reactor at 550\u0026deg;C and atmospheric pressure with a WHSV of 1.0 h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, using the parent and modified Z5-based catalysts. Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e offers a comprehensive assessment of the products, highlighting their performance and characteristics. The product distribution from light naphtha aromatization is typically categorized into liquid and gaseous fractions, as illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ea and Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eb, respectively. The liquid phase primarily consists of BTX aromatics along with C\u003csub\u003e5+\u003c/sub\u003e paraffins and olefins, whereas the gas phase includes C\u003csub\u003e1\u003c/sub\u003e, C\u003csub\u003e2\u003c/sub\u003e, C\u003csub\u003e2=\u003c/sub\u003e, and C\u003csub\u003e3\u003c/sub\u003e-C\u003csub\u003e4\u003c/sub\u003e hydrocarbons. All tested catalysts Z5, Z5-AT, 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT achieved near-complete conversion (99\u0026ndash;100%) of light straight-run (LSR) naphtha under reaction conditions of 550\u0026deg;C and atmospheric pressure.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe parent Z5 catalyst exhibited an aromatic yield of 31.9 wt.%, while desilicated Z5-AT demonstrated a significantly enhanced aromatic yield of 49.7 wt.%, approximately 1.5 times greater than that of microporous parent Z5. Further enhancement in aromatization activity was observed for the metal-modified catalysts 1%Zn/Z5-AT, 2%La/Z5-AT, and 2%La-1%Zn/Z5-AT catalysts can be attributed to a combination of: tailored acidity through metal incorporation and framework modification, (ii) enhanced dehydrogenation activity provided by Zn species, and (iii) improved mass transport from the mesoporous-microporous structure, with La contributing to acidity moderation and selectivity enhancement.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eProduct distribution in LSR naphtha aromatization over parent and modified ZSM-5 catalysts.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCatalyst\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZ5\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eZ5-AT\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1%Zn/Z5-AT\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2%La/Z5-AT\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2%La-1%Zn/Z5-AT\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNaphtha Conversion, %\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e99.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e99.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e99.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYield (wt.%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBenzene\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e15.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e17.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e32.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e16.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e33.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eToluene\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e21.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e26.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e20.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e26.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eXylenes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e10.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e7.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e12.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBTX\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e24.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e49.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e69.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e45.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e72.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEthyl benzene\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e9\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;Aromatics\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e1.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e5\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;Paraffins\u0026thinsp;+\u0026thinsp;Olefins\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e14.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTotal Aromatics\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e31.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e49.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e70.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e47.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e74.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e9.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e5.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e3.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e3.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e6.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e6.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e5.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e=\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e4.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003csub\u003e3\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;C\u003csub\u003e4\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e33.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e43.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e16.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e42.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e15.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTotal Paraffins\u0026thinsp;+\u0026thinsp;Olefins\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e53.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e49.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e29.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e52.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e25.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSum\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe correlation between L/B ratio, H\u003csub\u003e2\u003c/sub\u003e evolution, BTX yield, and total paraffins and olefins content across the ZSM-5-based catalysts reveals key structure-function relationships in naphtha aromatization (Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e). As the L/B ratio increases from 0.045 (Z5) to 1.95 (2%La-1%Zn/Z5-AT), both BTX and total aromatics yields improve significantly, indicating the crucial role of Lewis acid sites, particularly those introduced by Zn, in promoting dehydrogenation and aromatization. The highest H\u003csub\u003e2\u003c/sub\u003e evolution (9.09 mol%) observed for 1%Zn/Z5-AT confirms the role of Zn in enhancing alkane to olefin and olefin to aromatic pathways. Interestingly, the 2%La-1%Zn/Z5-AT catalyst exhibits the highest BTX yield (72.7 wt.%) but a slightly lower H\u003csub\u003e2\u003c/sub\u003e formation (7.70 mol%), suggesting that La incorporation modulates Zn dispersion and acidity in a way that enhances selectivity without excessive dehydrogenation. Whereas 2%La/Z5-AT exhibits a higher L/B ratio than Z5-AT, its BTX yield is slightly lower. This is likely due to La\u003csup\u003e3+\u003c/sup\u003e neutralizing Br\u0026oslash;nsted acid sites, reducing the cracking and olefin formation necessary for aromatization. While the Lewis acidity increases, the absence of a dehydrogenation function and diminished Br\u0026oslash;nsted activity limit the formation of BTX precursors, resulting in lower selectivity. In contrast, the parent Z5, with a low L/B ratio and lacking a dehydrogenation metal, exhibits poor BTX selectivity (24 wt.%) and high retention of paraffins and olefins (53.1 wt.%), highlighting the limitations of Br\u0026oslash;nsted acidity-dominated systems. Overall, the combined tuning of acid site distribution and metal function provides a synergistic pathway for boosting BTX production while controlling hydrocarbon cracking and gas formation.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe conversion of light naphtha involves multiple reaction pathways primarily governed by the carbenium mechanism, which facilitates cracking, isomerization, oligomerization, and cyclization at Br\u0026oslash;nsted acid sites. In contrast, the Lewis acid sites promote dehydrogenation and/or hydrogen transfer reactions.\u003csup\u003e\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e\u003c/sup\u003e During aromatization, the accumulation of larger intermediates on internal acid sites can lead to micropore blockage, causing coke formation and catalyst deactivation.\u003csup\u003e\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e\u003c/sup\u003e The adequate balance of acid sites significantly enhance the aromatization performance by supporting key steps in the reaction mechanism. Firstly, the alkanes are transformed into olefins by dissociative chemisorption, which are subsequently transformed into aromatics via cyclization and oligomerization on acidic sites.\u003csup\u003e\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eUniform dispersion of metal species over mesoporous zeolites enhances the aromatization by suppressing excessive cracking to lower olefins. Mesostructured zeolites enhance mass transfer, increase accessibility to acid sites, and facilitate better metal distribution, contributing to higher reaction efficiency. The total aromatics yields by the 1%Zn/Z5-AT and 2%La-1%Zn/Z5-AT catalysts are 70.6 wt.% and 74.4 wt.%, respectively, with a toluene-to-benzene ratio of approximately 0.5 for both catalysts. The high aromatic selectivity is attributed to the dehydrogenation function of Zn, while La plays a role in acidity tuning and diffusion control, enabling conversion of small paraffinic fragments (e.g., C\u003csub\u003e3\u003c/sub\u003e and C\u003csub\u003e4\u003c/sub\u003e) into aromatics via secondary reactions.\u003c/p\u003e\u003cp\u003eIn contrast, 2%La/Z5-AT catalysts yielded significantly lower aromatics (47 wt.%), which can be ascribed to limited dehydrogenation activity, increased olefin dimerization, and reduced Br\u0026oslash;nsted acidity. However, the gaseous olefin and paraffin products C\u003csub\u003e1\u003c/sub\u003e, C\u003csub\u003e2\u003c/sub\u003e, C\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e=\u003c/sup\u003e, and C\u003csub\u003e3\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;C\u003csub\u003e4\u003c/sub\u003e displayed a slight change with or without the addition of bimetallic species to Z5-AT. 2%La-1%Zn/Z5-AT, methane and ethane yields stabilized at ~\u0026thinsp;3.8 wt.% and 5.4 wt.%, respectively, during 1 h TOS, while C\u003csub\u003e3\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;C\u003csub\u003e4\u003c/sub\u003e hydrocarbons remained the dominant fraction (~\u0026thinsp;15.2 wt.%) influencing overall gas selectivity. These findings confirm that 2% La-1%Zn/Z5-AT is as an effective catalyst, with performance comparable to recently reported systems for light naphtha conversion, as summarized in \u003cb\u003eTable S2\u003c/b\u003e.\u003c/p\u003e\u003cp\u003eThe catalytic stability of Z5-AT and 2%La-1%Zn/Z5-AT for light naphtha aromatization was evaluated based on BTX and gaseous products yields, as shown in \u003cb\u003eFigure S3\u003c/b\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ec-d. Both Catalysts maintained consistent conversion levels, with Z5-AT showing commendable stability in BTX production. Notably, the 2%La-1%Zn/Z5-AT catalyst sustained a high BTX yield of 72.7 wt.% over 6 hours on stream, reflecting its robust performance. Catalyst deactivation, particularly in Z5, was primarily attributed to coke accumulation within micropores. The measured coke deposits on the spent catalysts as follows. Z5 (1.61 wt.%), Z5-AT (1.13 wt.%), 1%Zn/Z5-AT (1.58 wt.%), 2%La/Z5-AT (0.55 wt.%), and 2%La-1%Zn/Z5-AT (1.53 wt.%). The significantly reduced coke deposition observed in Z5-AT and 2%La/Z5-AT compared to Z5 confirms the beneficial role of mesoporosity and modified acidity in mitigating carbon buildup. These results indicate that introducing mesoporous architecture enhances catalyst stability by facilitating molecular diffusion and reducing pore blockage. Interestingly, despite moderate coke accumulation, the BTX yield for 2%La\u0026ndash;1%Zn/Z5-AT slightly increased with time-on-stream, suggesting that this catalyst resists deactivation and maintains active site accessibility. This study highlights the effectiveness of tailored mesoporous-microporous ZSM-5 structures for long-term naphtha aromatization and presents strategies to overcome limitations associated with microporous catalysts. The findings may also benefit other acid-catalyzed processes constrained by diffusional resistance or rapid deactivation.\u003c/p\u003e\u003c/div\u003e"},{"header":"4. Conclusions","content":"\u003cp\u003eThe micropores in the Z5 [Si/Al ratio of 30] structure limit the catalytic conversion of naphtha aromatization due to the diffusion constraints imposed by naphtha bulky feed molecules. To circumvent this, desilication in an alkaline solution resulted in the formation of homogeneous intracrystalline mesopores in Z5, improving molecular transport and enhancing hydrocracking and aromatization activity. The microporous Z5 produces 24 wt.% BTX, while the mesoporous Z5-AT demonstrates a markedly improved yield for aromatics at 49 wt.%. Further incorporation of optimal amounts of La and Zn introduced dehydrogenation functionality, enabling the modified Z5-AT to reach a maximum BTX yield of 72.7 wt.% at 550 °C. The uniform distribution of La and Zn species across the mesoporous matrix improved catalytic performance by boosting dehydrogenation, promoting aromatic ring formation, and suppressing undesired gaseous by-products. The synergistic interaction between zinc and lanthanum, combined with enhanced mesoporosity and a balanced distribution of Brønsted and Lewis acid sites, facilitated both cyclization and dehydrogenation pathways, thus maximizing aromatic selectivity and catalyst efficiency.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eASSOCIATED CONTENT\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSupporting Information \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Supporting Information contains: \u003c/p\u003e\n\u003cp\u003eNH\u003csub\u003e3\u003c/sub\u003e-TPD profiles of parent Z5 material; acid quantities of several zeolite samples as calculated from NH\u003csub\u003e3\u003c/sub\u003e-TPD profiles; EDX spectrum of 2%La-1%Zn/Z5-AT material; stability test results of Z5-AT catalyst samples; liquid yield stability, gas yield stability.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCorresponding Author\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eZiyauddin S. Qureshi\u003c/strong\u003e-\u003cem\u003e Interdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum \u0026amp; Minerals, Dhahran 31261, Saudi Arabia, Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia; \u003c/em\u003e\u003cstrong\u003e\u003cem\u003ehttps://orcid.org/0000-0002-5033-9016\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eE-mail: \u003c/em\u003e\u003cstrong\u003e\u003cem\[email protected]\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMuhammad Waqas\u003cem\u003e-\u003c/em\u003e\u003c/strong\u003e\u003cem\u003eInterdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum \u0026amp; Minerals, Dhahran 31261, Saudi Arabia\u003c/em\u003e\u003cem\u003e, \u003c/em\u003e\u003cstrong\u003e\u003cem\u003ehttps://orcid.org/0000-0002-4249-3857\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTatinaidu Kella-\u003c/strong\u003e \u003cem\u003eInterdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum \u0026amp; Minerals, Dhahran 31261, Saudi Arabia, \u003c/em\u003e\u003cstrong\u003e\u003cem\u003ehttps://orcid.org/0000-0003-4936-9821\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eYaming Jin- \u003c/strong\u003e\u003cem\u003eResearch \u0026amp; Development Center, Saudi Aramco, Dhahran 31311, Saudi Arabia\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAbdullah M. Aitani-\u003c/strong\u003e\u003cem\u003eInterdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum \u0026amp; Minerals, Dhahran 31261, Saudi Arabia, Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia\u003c/em\u003e\u003cem\u003e, \u003c/em\u003e\u003cstrong\u003e\u003cem\u003ehttps://orcid.org/0000-0001-5071-4034\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHassan Alasiri- \u003c/strong\u003e\u003cem\u003eInterdisciplinary Research Center for Refining and Advanced Chemicals, King Fahd University of Petroleum \u0026amp; Minerals, Dhahran 31261, Saudi Arabia, Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia, \u003c/em\u003e\u003cstrong\u003e\u003cem\u003ehttps://orcid.org/0000-0003-4043-5677\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eNotes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing financial interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors are grateful to Saudi Aramco for funding for project CRP02283. We greatly appreciate the assistance from King Fahd University of Petroleum \u0026amp; Minerals (KFUPM), Dhahran, Saudi Arabia.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAkhtar, M. N.; Aitani, A. M.; Ummer, A. C.; Alasiri, H. S. Review on the Catalytic Conversion of Naphtha to Aromatics: Advances and Outlook. \u003cem\u003eEnergy. Fuels. \u003c/em\u003e\u003cstrong\u003e2023\u003c/strong\u003e, \u003cem\u003e37\u003c/em\u003e, 2586-2607. \u003c/li\u003e\n\u003cli\u003eSong, S., Li, T., Ju, Y., Li, Y., Lv, Z., Zheng, P., ... \u0026amp; Wang, X. Lanthanum/Gallium-modified Zn/ZSM-5 zeolite for efficient isomerization/aromatization of FCC light gasoline. Ind. Eng. Chem. Res. \u003cstrong\u003e2022\u003c/strong\u003e, 61, 9667-9677.\u003c/li\u003e\n\u003cli\u003eUmmer, A. C., Akhtar, M. N., Alnaimi, E., Ding, L., \u0026amp; Alasiri, H. S. Aromatization of Commercial Full Range Naphtha Over Modified Hierarchical ZSM‐5 Catalyst. ChemistrySelect. \u003cstrong\u003e2021\u003c/strong\u003e, 6, 11541-11550.\u003c/li\u003e\n\u003cli\u003ellouh, M.; Qureshi, Z. S.; Aitani, A.; Akhtar, M. N.; Jin, Y.; Koseoglu, O.; Alasiri, H. Light paraffinic naphtha to BTX aromatics over metal‐modified Pt/ZSM‐5. \u003cem\u003eChemistrySelect. \u003c/em\u003e\u003cstrong\u003e2020\u003c/strong\u003e, \u003cem\u003e5\u003c/em\u003e, 13807-13813.\u003c/li\u003e\n\u003cli\u003eEgolf, B.; Lafyatis, D.; Serban, M.; Lok, K.; Lapinski, M. The Honeywell UOP CCR Platforming\u0026trade; Process for BTX Production (Case Study). In \u003cem\u003eIndustrial Arene Chemistry\u003c/em\u003e, \u003cstrong\u003e2023\u003c/strong\u003e; pp 269-295.\u003c/li\u003e\n\u003cli\u003eFung, S. C. Deactivation and Regeneration/Redispersion Chemistry of Pt/KL-Zeolite. In \u003cem\u003eStudies in Surface Science and Catalysis\u003c/em\u003e, Spivey, J. J., Roberts, G. W., Davis, B. H. Eds.; Vol. 139; Elsevier, \u003cstrong\u003e2001\u003c/strong\u003e; pp 399-406.\u003c/li\u003e\n\u003cli\u003eRodr\u0026iacute;guez, M. A.; Ancheyta, J. Detailed description of kinetic and reactor modeling for naphtha catalytic reforming. \u003cem\u003eFuel. \u003c/em\u003e\u003cstrong\u003e2011\u003c/strong\u003e, \u003cem\u003e90\u003c/em\u003e, 3492-3508. \u003c/li\u003e\n\u003cli\u003eHughes, T. R.; Buss, W. C.; Tamm, P. W.; Jacobson, R. L. Aromatization of Hydrocarbons over Platinum Alkaline Earth Zeolites. In \u003cem\u003eStudies in Surface Science and Catalysis\u003c/em\u003e, Murakami, Y., Iijima, A., Ward, J. W. Eds.; Vol. 28; Elsevier, \u003cstrong\u003e1986\u003c/strong\u003e; pp 725-732.\u003c/li\u003e\n\u003cli\u003eAitani, A.; Akhtar, M. N.; Al-Khattaf, S.; Jin, Y.; Koseoglo, O.; Klein, M. T. Catalytic Upgrading of Light Naphtha to Gasoline Blending Components: A Mini Review. \u003cem\u003eEnerg. Fuels. \u003c/em\u003e\u003cstrong\u003e2019\u003c/strong\u003e, \u003cem\u003e33\u003c/em\u003e, 3828-3843. \u003c/li\u003e\n\u003cli\u003eFalter, Christoph. Solar Thermochemical Fuels. \u003cem\u003eConversion of Water and CO\u003csub\u003e2\u003c/sub\u003e to Fuels using Solar Energy: Science, Technology and Materials. \u003c/em\u003e\u003cstrong\u003e2024\u003c/strong\u003e, 47-82. \u003c/li\u003e\n\u003cli\u003eQureshi, Z. S.; Ellouh, M.; Aitani, A.; Akhtar, M. N.; Jin, Y.; Koseoglu, O.; Alasiri, H. Efficient conversion of light paraffinic naphtha to aromatics over metal-modified Mo/MFI catalysts. \u003cem\u003eJ. Porous Mater. \u003c/em\u003e\u003cstrong\u003e2022\u003c/strong\u003e, \u003cem\u003e29\u003c/em\u003e, 683-692. \u003c/li\u003e\n\u003cli\u003eWu, Y.; Yang, J.; Wu, G.; Gao, W.; Silva Lora, E. E.; Isa, Y. M.; Subramanian, K. A.; Kozlov, A.; Zhang, S.; Huang, Y. Benzene, toluene, and xylene (BTX) production from catalytic fast pyrolysis of biomass: a review. \u003cem\u003eACS Sustain. Chem. Eng. \u003c/em\u003e\u003cstrong\u003e2023\u003c/strong\u003e, \u003cem\u003e11\u003c/em\u003e, 11700-11718.\u003c/li\u003e\n\u003cli\u003eWaqas, M.; Qureshi, Z. S.; Siddiqui, M. A.; Aitani, A.; Akah, A. C. Development of hierarchical ZSM-11 for synthesis of light olefins from crude oil. \u003cem\u003eJ. Anal. Appl. Pyrolysis. \u003c/em\u003e\u003cstrong\u003e2024\u003c/strong\u003e, 185, 106870.\u003c/li\u003e\n\u003cli\u003eShamzhy, M.; Opanasenko, M.; Concepci\u0026oacute;n, P.; Mart\u0026iacute;nez, A. New trends in tailoring active sites in zeolite-based catalysts. \u003cem\u003eChem. Soc. Rev. \u003c/em\u003e\u003cstrong\u003e2019\u003c/strong\u003e, \u003cem\u003e48\u003c/em\u003e, 1095-1149. \u003c/li\u003e\n\u003cli\u003eMole, T.; Anderson, J. R.; Creer, G. The reaction of propane over ZSM-5-H and ZSM-5-Zn zeolite catalysts. \u003cem\u003eApplied catalysis \u003c/em\u003e\u003cstrong\u003e1985\u003c/strong\u003e, \u003cem\u003e17\u003c/em\u003e, 141-154. \u003c/li\u003e\n\u003cli\u003eGuisnet, M.; Gnep, N. S.; Alario, F. Aromatization of short chain alkanes on zeolite catalysts. \u003cem\u003eAppl. Catal. A: Gen. \u003c/em\u003e\u003cstrong\u003e1992\u003c/strong\u003e, \u003cem\u003e89\u003c/em\u003e, 1-30.\u003c/li\u003e\n\u003cli\u003ePan, D.; Song, X.; Yang, X.; Gao, L.; Wei, R.; Zhang, J.; Xiao, G. Efficient and selective conversion of methanol to para-xylene over stable H [Zn, Al] ZSM-5/SiO\u003csub\u003e2\u003c/sub\u003e composite catalyst. \u003cem\u003eAppl. Catal. A: Gen. \u003c/em\u003e\u003cstrong\u003e2018\u003c/strong\u003e, \u003cem\u003e557\u003c/em\u003e, 15-24.\u003c/li\u003e\n\u003cli\u003eZhang, J.; Qian, W.; Kong, C.; Wei, F. Increasing para-xylene selectivity in making aromatics from methanol with a surface-modified Zn/P/ZSM-5 catalyst. \u003cem\u003eACS Catal. \u003c/em\u003e\u003cstrong\u003e2015\u003c/strong\u003e, \u003cem\u003e5\u003c/em\u003e, 2982-2988.\u003c/li\u003e\n\u003cli\u003eMiyamoto, M.; Mabuchi, K.; Kamada, J.; Hirota, Y.; Oumi, Y.; Nishiyama, N.; Uemiya, S. para-Selectivity of silicalite-1 coated MFI type galloaluminosilicate in aromatization of light alkanes. \u003cem\u003eJ. Porous Mater. \u003c/em\u003e\u003cstrong\u003e2015\u003c/strong\u003e, \u003cem\u003e22\u003c/em\u003e, 769-778. \u003c/li\u003e\n\u003cli\u003eFrey, K.; Lubango, L. M.; Scurrell, M. S.; Guczi, L. Erratum to: Light alkane aromatization over modified Zn-ZSM-5 catalysts: characterization of the catalysts by hydrogen/deuterium isotope exchange. \u003cem\u003eReact. Kinet. Mech. Catal. \u003c/em\u003e\u003cstrong\u003e2011\u003c/strong\u003e, \u003cem\u003e104\u003c/em\u003e, 311.\u003c/li\u003e\n\u003cli\u003eDong, S.; Ryu, T.; Oi, C.; Wu, J.; Altvater, N. R.; Hagmann, R.; Alikhani, Z.; Lebr\u0026oacute;n-Rodr\u0026iacute;guez, E. A.; Jansen, J. H.; Cecon, V. S. Catalytic conversion of post-consumer recycled high-density polyethylene oil over Zn-impregnated ZSM-5 catalysts. \u003cem\u003eChem. Eng. J. \u003c/em\u003e\u003cstrong\u003e2024\u003c/strong\u003e, \u003cem\u003e482\u003c/em\u003e, 148889.\u003c/li\u003e\n\u003cli\u003eUmmer, A. C.; Akhtar, M. N.; Alnaimi, E.; Alasiri, H. S.; Ding, L.; Sanhoob, M. A.; Alotaibi, F. Understanding the Promotional Effect of Silver in Naphtha Reforming over a Ga/ZSM-5 Catalyst to Enhance Liquid Yield. \u003cem\u003eThe J. Phy. Chem. C. \u003c/em\u003e\u003cstrong\u003e2024\u003c/strong\u003e, \u003cem\u003e128\u003c/em\u003e, 1971-1981. \u003c/li\u003e\n\u003cli\u003eAnekwe, I. M. S.; Chetty, M.; Khotseng, L.; Kiambi, S. L.; Maharaj, L.; Oboirien, B.; Isa, Y. M. Stability, deactivation and regeneration study of a newly developed HZSM-5 and Ni-doped HZSM-5 zeolite catalysts for ethanol-to-hydrocarbon conversion. \u003cem\u003eCatal. Commun. \u003c/em\u003e\u003cstrong\u003e2024\u003c/strong\u003e, \u003cem\u003e186\u003c/em\u003e, 106802. \u003c/li\u003e\n\u003cli\u003eQian, K.; Tian, W.; Yan, S.; Li, W.; Yin, L.; Guo, D.; Yang, Z.; Chen, D.; Feng, Y. Aromatization of HDPE and PP over Ga-promoted zeolite: Effects of pretreatment and zeolite type. \u003cem\u003eFuel. \u003c/em\u003e\u003cstrong\u003e2024\u003c/strong\u003e, \u003cem\u003e357\u003c/em\u003e, 129781. \u003c/li\u003e\n\u003cli\u003eZheng, S.; Heydenrych, H. R.; Jentys, A.; Lercher, J. A. Influence of surface modification on the acid site distribution of HZSM-5. J. Phy. Chem. B. \u003cstrong\u003e2002\u003c/strong\u003e, \u003cem\u003e106\u003c/em\u003e, 9552-9558. \u003c/li\u003e\n\u003cli\u003eHibino, T.; Niwa, M.; Murakami, Y. Shape-selectivity over HZSM-5 modified by chemical vapor deposition of silicon alkoxide. \u003cem\u003eJ. Catal. \u003c/em\u003e\u003cstrong\u003e1991\u003c/strong\u003e, \u003cem\u003e128\u003c/em\u003e, 551-558.\u003c/li\u003e\n\u003cli\u003eLischke, G.; Eckelt, R.; Jerschkewitz, H. G.; Parlitz, B.; Schreier, E.; Storek, W.; Zibrowius, B.; \u0026Ouml;hlmann, G. Spectroscopic and physicochemical characterization of P-modified H-ZSM-5. \u003cem\u003eJ. Catal. \u003c/em\u003e\u003cstrong\u003e1991\u003c/strong\u003e, \u003cem\u003e132\u003c/em\u003e, 229-243.\u003c/li\u003e\n\u003cli\u003eXue, B.; Zhang, G.; Liu, N.; Xu, J.; Shen, Q.; Li, Y. Highly selective synthesis of para-diethylbenzene by alkylation of ethylbenzene with diethyl carbonate over boron oxide modified HZSM-5. \u003cem\u003eJ. Mol. Catal. A Chem. \u003c/em\u003e\u003cstrong\u003e2014\u003c/strong\u003e, \u003cem\u003e395\u003c/em\u003e, 384-391.\u003c/li\u003e\n\u003cli\u003eZhang, J.; Zhu, X.; Wang, G.; Wang, P.; Meng, Z.; Li, C. The origin of the activity and selectivity of silicalite-1 zeolite for toluene methylation to para-xylene. \u003cem\u003eChem. Eng. J. \u003c/em\u003e\u003cstrong\u003e2017\u003c/strong\u003e, \u003cem\u003e327\u003c/em\u003e, 278-285.\u003c/li\u003e\n\u003cli\u003eLi, J.; Tong, K.; Xi, Z.; Yuan, Y.; Hu, Z.; Zhu, Z. Highly-efficient conversion of methanol to p-xylene over shape-selective Mg\u0026ndash;Zn\u0026ndash;Si-HZSM-5 catalyst with fine modification of pore-opening and acidic properties. \u003cem\u003eCatal. Sci. Technol. \u003c/em\u003e\u003cstrong\u003e2016\u003c/strong\u003e, \u003cem\u003e6\u003c/em\u003e, 4802-4813.\u003c/li\u003e\n\u003cli\u003eGroen, J. C.; Moulijn, J. A.; P\u0026eacute;rez-Ram\u0026iacute;rez, J. Alkaline posttreatment of MFI zeolites. From accelerated screening to scale-up. \u003cem\u003eInd. Eng. Chem. Res. \u003c/em\u003e\u003cstrong\u003e2007\u003c/strong\u003e, \u003cem\u003e46\u003c/em\u003e, 4193-4201. \u003c/li\u003e\n\u003cli\u003eZhao, H.; Ma, J.; Zhang, Q.; Liu, Z.; Li, R. Adsorption and diffusion of n-heptane and toluene over mesoporous ZSM-5 zeolites. \u003cem\u003eInd. Eng. Chem. Res. \u003c/em\u003e\u003cstrong\u003e2014\u003c/strong\u003e, \u003cem\u003e53\u003c/em\u003e, 13810-13819.\u003c/li\u003e\n\u003cli\u003eVerboekend, D.; P\u0026eacute;rez-Ram\u0026iacute;rez, J. Design of hierarchical zeolite catalysts by desilication. \u003cem\u003eCatal. Sci. Technol. \u003c/em\u003e\u003cstrong\u003e2011\u003c/strong\u003e, \u003cem\u003e1\u003c/em\u003e, 879-890. \u003c/li\u003e\n\u003cli\u003eTao, H.; Yang, H.; Liu, X.; Ren, J.; Wang, Y.; Lu, G. Highly stable hierarchical ZSM-5 zeolite with intra-and inter-crystalline porous structures. \u003cem\u003eChem. Eng J. \u003c/em\u003e\u003cstrong\u003e2013\u003c/strong\u003e, \u003cem\u003e225\u003c/em\u003e, 686-694.\u003c/li\u003e\n\u003cli\u003eTarach, K. A.; Martinez-Triguero, J.; Rey, F.; G\u0026oacute;ra-Marek, K. Hydrothermal stability and catalytic performance of desilicated highly siliceous zeolites ZSM-5. \u003cem\u003eJ. Catal. \u003c/em\u003e\u003cstrong\u003e2016\u003c/strong\u003e, \u003cem\u003e339\u003c/em\u003e, 256-269.\u003c/li\u003e\n\u003cli\u003eAlmutairi, S. M. T.; Mezari, B.; Magusin, P. C. M. M.; Pidko, E. A.; Hensen, E. J. M. Structure and reactivity of Zn-modified ZSM-5 zeolites: the importance of clustered cationic Zn complexes. \u003cem\u003eACS. Catal. \u003c/em\u003e\u003cstrong\u003e2012\u003c/strong\u003e, \u003cem\u003e2\u003c/em\u003e, 71-83.\u003c/li\u003e\n\u003cli\u003eVishwanathan, V.; Jun, K.-W.; Kim, J.-W.; Roh, H.-S. Vapour phase dehydration of crude methanol to dimethyl ether over Na-modified H-ZSM-5 catalysts. \u003cem\u003eAppl. Catal. A: Gen. \u003c/em\u003e\u003cstrong\u003e2004\u003c/strong\u003e, \u003cem\u003e276\u003c/em\u003e, 251-255.\u003c/li\u003e\n\u003cli\u003eAhn, J. H.; Kolvenbach, R.; Neudeck, C.; Al-Khattaf, S. S.; Jentys, A.; Lercher, J. A. Tailoring mesoscopically structured H-ZSM5 zeolites for toluene methylation. \u003cem\u003eJ. Catal. \u003c/em\u003e\u003cstrong\u003e2014\u003c/strong\u003e, \u003cem\u003e311\u003c/em\u003e, 271-280. \u003c/li\u003e\n\u003cli\u003eZhou, F.; Gao, Y.; Wu, G.; Ma, F.; Liu, C. Improved catalytic performance and decreased coke formation in post-treated ZSM-5 zeolites for methanol aromatization. \u003cem\u003eMicropor. Mesop Mate. \u003c/em\u003e\u003cstrong\u003e2017\u003c/strong\u003e, \u003cem\u003e240\u003c/em\u003e, 96-107.\u003c/li\u003e\n\u003cli\u003eVerboekend, D.; Mitchell, S.; Milina, M.; Groen, J. C.; P\u0026eacute;rez-Ram\u0026iacute;rez, J. Full compositional flexibility in the preparation of mesoporous MFI zeolites by desilication. \u003cem\u003eJ. Phys Chem. C. \u003c/em\u003e\u003cstrong\u003e2011\u003c/strong\u003e, \u003cem\u003e115\u003c/em\u003e, 14193-14203.\u003c/li\u003e\n\u003cli\u003eSu, X.; Zan, W.; Bai, X.; Wang, G.; Wu, W. Synthesis of microscale and nanoscale ZSM-5 zeolites: effect of particle size and acidity of Zn modified ZSM-5 zeolites on aromatization performance. \u003cem\u003eCatal. Sci. Technol. \u003c/em\u003e\u003cstrong\u003e2017\u003c/strong\u003e, \u003cem\u003e7\u003c/em\u003e, 1943-1952.\u003c/li\u003e\n\u003cli\u003eLong, X.; Zhang, Q.; Liu, Z.-T.; Qi, P.; Lu, J.; Liu, Z.-W. Magnesia modified H-ZSM-5 as an efficient acidic catalyst for steam reforming of dimethyl ether. \u003cem\u003eAppl. Catal. B: Environ. \u003c/em\u003e\u003cstrong\u003e2013\u003c/strong\u003e, \u003cem\u003e134\u003c/em\u003e, 381-388. \u003c/li\u003e\n\u003cli\u003eSong, Z.; Takahashi, A.; Nakamura, I.; Fujitani, T. Phosphorus-modified ZSM-5 for conversion of ethanol to propylene. \u003cem\u003eAppl. Catal. A: Gen. \u003c/em\u003e\u003cstrong\u003e2010\u003c/strong\u003e, \u003cem\u003e384\u003c/em\u003e, 201-205.\u003c/li\u003e\n\u003cli\u003eNiu, X.; Gao, J.; Wang, K.; Miao, Q.; Dong, M.; Wang, G.; Fan, W.; Qin, Z.; Wang, J. Influence of crystal size on the catalytic performance of H-ZSM-5 and Zn/H-ZSM-5 in the conversion of methanol to aromatics. \u003cem\u003eFuel Process. Technol. \u003c/em\u003e\u003cstrong\u003e2017\u003c/strong\u003e, \u003cem\u003e157\u003c/em\u003e, 99-107.\u003c/li\u003e\n\u003cli\u003eBerndt, H.; Lietz, G.; V\u0026ouml;lter, J. Zinc promoted H-ZSM-5 catalysts for conversion of propane to aromatics II. Nature of the active sites and their activation. \u003cem\u003eAppl. Catal. A: Gen. \u003c/em\u003e\u003cstrong\u003e1996\u003c/strong\u003e, \u003cem\u003e146\u003c/em\u003e, 365-379.\u003c/li\u003e\n\u003cli\u003eLi, F.; Ding, S.; Wang, Z.; Li, Z.; Li, L.; Gao, C.; Zhong, Z.; Lin, H.; Chen, C. Production of light olefins from catalytic cracking bio-oil model compounds over La2O3-modified ZSM-5 zeolite. \u003cem\u003eEnerg. fuels. \u003c/em\u003e\u003cstrong\u003e2018\u003c/strong\u003e, \u003cem\u003e32\u003c/em\u003e, 5910-5922.\u003c/li\u003e\n\u003cli\u003eSang, Y.; Li, H. Effect of phosphorus and mesopore modification on the HZSM-5 zeolites for n-decane cracking. \u003cem\u003eJ. Solid State Chem. \u003c/em\u003e\u003cstrong\u003e2019\u003c/strong\u003e, \u003cem\u003e271\u003c/em\u003e, 326-333.\u003c/li\u003e\n\u003cli\u003eOno, Y. Transformation of lower alkanes into aromatic hydrocarbons over ZSM-5 zeolites. \u003cem\u003eCatalysis Reviews \u003c/em\u003e\u003cstrong\u003e1992\u003c/strong\u003e, \u003cem\u003e34\u003c/em\u003e, 179-226.\u003c/li\u003e\n\u003cli\u003eM\u0026Eacute;Riaudeau, P.; Naccache, C. Dehydrocyclization of alkanes over zeolite-supported metal catalysts: monofunctional or bifunctional route. \u003cem\u003eCatal. Rev. \u003c/em\u003e\u003cstrong\u003e1997\u003c/strong\u003e, \u003cem\u003e39\u003c/em\u003e, 5-48.\u003c/li\u003e\n\u003cli\u003eLee, K.; Lee, S.; Jun, Y.; Choi, M. Cooperative effects of zeolite mesoporosity and defect sites on the amount and location of coke formation and its consequence in deactivation. \u003cem\u003eJ. Catal. \u003c/em\u003e\u003cstrong\u003e2017\u003c/strong\u003e, \u003cem\u003e347\u003c/em\u003e, 222-230.\u003c/li\u003e\n\u003cli\u003eSu, X.; Fang, Y.; Bai, X.; Wu, W. Synergic effect of GaO+/Br\u0026oslash;nsted acid in hierarchical Ga/Al-ZSM-5 bifunctional catalysts for 1-hexene aromatization. \u003cem\u003eInd. Eng. Chem. Res. \u003c/em\u003e\u003cstrong\u003e2019\u003c/strong\u003e, \u003cem\u003e58\u003c/em\u003e, 20543-20552.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-porous-materials","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jopo","sideBox":"Learn more about [Journal of Porous Materials](http://link.springer.com/journal/10934)","snPcode":"10934","submissionUrl":"https://submission.nature.com/new-submission/10934/3","title":"Journal of Porous Materials","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Mesostructured zeolite, Bimetallic catalyst, Naphtha aromatization, Dehydrogenation, BTX aromatics, petrochemicals","lastPublishedDoi":"10.21203/rs.3.rs-7408317/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7408317/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eDiffusion limitations in microporous ZSM-5 zeolites hinder the efficient aromatization of light naphtha into valuable BTX (benzene, toluene, xylenes). In this work, we report the development of a mesostructured bimetallic catalyst through controlled alkaline desilication of ZSM-5 (Z5), followed by the incorporation of 2 wt.% La and 1 wt.% Zn via wet impregnation. The desilicated zeolite (Z5-AT) exhibited enhanced mesoporosity, improving molecular diffusion and boosting BTX yield from 24 wt.% (Z5) to 49 wt.%. Further metal modification significantly enhanced performance, with the optimized 2%La-1%Zn/Z5-AT catalyst achieving a BTX yield of 72.7 wt.% at 550 °C in a fixed-bed down-flow reactor. Zn incorporation enhances the Lewis-to-Brønsted acid site (L/B) ratio, which accelerates dehydrogenation activity and promotes higher BTX formation. Textural and acidity characterizations confirmed uniform metal dispersion, improved surface area, and a favorable increase in L/B ratio. In-situ pyridine-FTIR and NH\u003csub\u003e3\u003c/sub\u003e-TPD analyses revealed synergistic effects between La and Zn, promoting dehydrogenation, acidity tuning, and coke suppression. These results demonstrate the effectiveness of mesostructured bimetallic ZSM-5 in enhancing light naphtha aromatization, with high aromatic selectivity and improved stability.\u003c/p\u003e","manuscriptTitle":"Mesostructured Bimetallic MFI Zeolite for Efficient Aromatization of Light Naphtha to BTX Aromatics","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-03 09:12:57","doi":"10.21203/rs.3.rs-7408317/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-09-14T13:14:07+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-10T07:12:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"220533100030113266169291433671694217961","date":"2025-08-27T00:41:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"63497085637215345301824654802463118239","date":"2025-08-26T22:45:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"217082341656800145521440423038070744759","date":"2025-08-26T21:46:37+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"267490577331280660977919434605787777899","date":"2025-08-26T21:39:40+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-08-26T20:29:37+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-08-20T11:49:52+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-20T11:47:59+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Porous Materials","date":"2025-08-19T11:47:01+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-porous-materials","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jopo","sideBox":"Learn more about [Journal of Porous Materials](http://link.springer.com/journal/10934)","snPcode":"10934","submissionUrl":"https://submission.nature.com/new-submission/10934/3","title":"Journal of Porous Materials","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"2335e72c-fb94-4f15-b08a-46dfaf914d80","owner":[],"postedDate":"September 3rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-08T16:02:42+00:00","versionOfRecord":{"articleIdentity":"rs-7408317","link":"https://doi.org/10.1007/s10934-025-01879-7","journal":{"identity":"journal-of-porous-materials","isVorOnly":false,"title":"Journal of Porous Materials"},"publishedOn":"2025-12-05 15:57:59","publishedOnDateReadable":"December 5th, 2025"},"versionCreatedAt":"2025-09-03 09:12:57","video":"","vorDoi":"10.1007/s10934-025-01879-7","vorDoiUrl":"https://doi.org/10.1007/s10934-025-01879-7","workflowStages":[]},"version":"v1","identity":"rs-7408317","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7408317","identity":"rs-7408317","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}