Chemical free and hydrophobic carbon paper for effective separation emulsified oil/water mixture based on cellulose and micro glass fiber

Chemical free and hydrophobic carbon paper for effective separation emulsified oil/water mixture based on cellulose and micro glass fiber | 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 Chemical free and hydrophobic carbon paper for effective separation emulsified oil/water mixture based on cellulose and micro glass fiber Qian Yang, Mingyue Zhao, Lanfeng Hui, Jieting Xin, Tingting Zhang, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5086335/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 17 Feb, 2025 Read the published version in Cellulose → Version 1 posted 4 You are reading this latest preprint version Abstract Separating emulsified oil/water mixture is full of challenges. Special permeable wetted surfaces can separate emulsions but usually require modification by fluorine or silicon based chemicals, which can cause second pollution after use. Carbon aerogels are new chemical free porous hydrophobic materials, which provide a promising approach to selectively adsorb oil from oil water mixture. However, during the course of the fabrication of carbon aerogels, freeze drying is essential, which is time-consuming and energy-intensive process. In this article, we introduced wet papermaking technology manufacturing base paper to replace freeze drying, followed by carbonization in N 2 at 800 ºC, hydrophobic carbon paper with a porosity of 90.22% was obtained when the content of micro glass fiber was 70%. The resulting carbon paper not only separates oil slick but also separates emulsified oil/water mixture with an efficiency of 98.5% and flux 1200 L/m 2 ·h. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 1. Introduction Fuel oil and organic solvents are important resources for human life, if they are mixed with water due to unexpected circumstances will cause a waste of resources. According to the existing form of oil/water mixture, oily sewage can be divided into an oil-water incompatible mixture (oil slick), unstable dispersed phase and stable emulsion (Abuhantash et al., 2023 ). Among them, the separation of the oil slick is relatively simple, because there is a density difference, and easy to divide into two layers, the appropriate selection of “water removing type” (Teng et al., 2020 ; Zhao et al, 2024 ) or “oil moving type” (Xu et al., 2024 ; Wahid et al., 2021 ) materials can effectively separate useful oils from the harmful mixture. The separation of the emulsified oil-water mixture is still full of challenges because emulsions have good stability and smaller diameters (less than 20 µm). Traditionally, chemical or flotation demulsification methods are used but gradually restricted or even prohibited due to low efficiency and high energy consumption. Currently, materials with special wetted surfaces were introduced to separate emulsified oil/water mixture, the main factors affecting the surface wettability were surface free energy and surface geometrical structure (Yang et al., 2023 ; Xian et al., 2023 ). At present, silicon (Han et al., 2024 ) or fluorine (He et al., 2024 ) based chemicals are used to reduce the surface free energy, which is usually expensive and causes secondary pollution (Bai et al., 2023 ; Li et al., 2023 ; Zheng et al., 2023 ). Therefore, the development of environmentally friendly and reliable oil/water separation materials without the use of chemicals has become a hot research and development. Additionally, the pore size of normal separation materials is too big to separate the emulsified mixture (Firmanda et al., 2023 ; Peng et al., 2023 ; Lang et al., 2023 ). Wang et al. ( 2015 ) designed two layers of superhydrophilic sponge, the separation efficiency of the micrometer porous layer is much lower than the nanometer porous layer, which indicated that the pore size was particularly important for the separation efficiency of emulsified oil/water mixture. Soffer et al. ( 1999 ) applied for the patent of cellulose carbonization, in the process of carbonization, cellulose was depolymerized into monosaccharides, then formed condensed aromatic structures and released gases containing non-carbon atoms (Kawamoto et al., 2003 ). Cellulose based carbon aerogel has a large specific surface area and porosity, low density, lightweight, flame retardant and conductive, and more importantly, its surface is oleophilic and hydrophobic in the absence of chemicals (Dong et al., 2021 : Lang et al., 2023 ), therefore, the separation of an oil-water mixture by carbon aerogel has become a hot research topic in recent years. Han et al. ( 2016 ) prepared hydrophobic porous carbon aerogel from waste newspaper via the process of freeze-drying and carbonization for organic pollution control. However, the production process of carbon aerogel is complex, because freeze drying is time-consuming and has high energy consumption. Besides, during the carbonization, the product shrunk as high as more than half (Jiao et al., 2016 ). In this experiment, unbleached kraft pulp and micro glass fiber were used as the raw materials to prepare the base paper with porous structure by the wet-end papermaking method, and then the carbon paper with porosity of 90.22% was obtained by the carbonization process under N 2 (Fig. 1 ). The carbon paper was hydrophobic and oleophilic, and the water contact angle reached 140 º, which could be hydrophobic in both air and oil. The thickness was only 0.32 mm, and the separation efficiency of the oil slick and emulsified oil were more than 99% and 98.5% respectively only under gravity. 2. Materials and methods 2.1. Materials Unbleached Kraft pulp was obtained from Shandong Huatai Group with beating degree of 33ºSR. Micro glass fiber was purchased from Unifrax (Shanghai) Co., LTD, diameter of 2.44 µm. High purity nitrogen was purchased from Tianjin Junliang City Changfu Gas Co., LTD., with a purity of 99.999%. Other chemicals were obtained from local suppliers and used as received. 2.2. Preparation of base paper Micro glass fiber was dispersed in pH = 4.6 solution at 600 rpm for 5 min, unbleached Kraft pulp was dispersed in a fiber standard dissociator (L&W, Sweden) for 10000 r. Mixed the dispersed micro glass fiber with the pulp solution (pulp suspensions), and stirred for 5000 r, the mixture was well dispersed and made 100 g/m 2 base weight base paper by hand sheet former machine (PTI, Austria). 2.3. Preparation of carbon paper The base paper was cut into 4 cm squares, and the carbonization process was carried out in a tubular furnace. Before the pyrolysis treatment, displacing the air in the furnace with N 2 , the sample was heated to 150 ºC at a heating rate of 10 ºC/min and maintained for 60 min, then heated to 450 ºC at a heating rate of 5 ºC/min and maintained for 60 min, finally heated to 800 ºC at a heating rate of 3 ºC/min and maintained for 120 min. Stopping heating, and the temperature was self cooled to room temperature under the protection of N 2 , the carbon paper was obtained. 2.4. Characterization The maximum pore size, mean pore size, minimum pore size, number of pores and porosity of samples (diameter 15 mm) were tested by capillary pore diameter measuring instrument (Quantachrome, America). Surface morphologies were investigated by scanning electron microscopy (SEM, Hitachi, Japan). Energy disperse spectroscopy (EDS) was measured by X-Max N (Oxford Instruments, British). The crystal structures were tested at a scan rate of 4 º/min from 10 to 40 º by X-ray diffractometer (XRD, Rigaku, Japan). X-ray photoelectron spectroscopy data was recorded using EscaLab 250Xi (XPS, Thermo Fisher, America). Water contact angle (WCA) was measured with 3 µL of deionized water by a dynamic contact angle measuring instrument PGX (Fibro, Sweden). Thermo gravimetric analysis (TGA) was conducted by TGA-50 (Shimadzu, Japan) with a heating rate of 20 ºC min − 1 to 800 ºC under N 2 atmosphere. 2.5. Oil/water mixture separation Oil slick: 10 mL of dichloromethane (dye with Sudan red) and 10 mL of water (dyed with methyl blue) were mixed and stirred, the carbon paper (area 1.76 cm 2 ) was fixed in the separation device and the oil/water mixture was poured above, water was repelled on the carbon paper and dichloromethane was collected below, the separation efficiency ( E ff , %) was calculated according to the equation: $$\:{E}_{ff}={v}_{1}/10\ast\:100\%$$ 1 where \(\:{v}_{1}\) represented the volume of collected dichloromethane. Emulsified oil: Mixed kerosene and water with a volume ratio of 99:1, the mixture was dispersed by high speed dispersing machine T18 (IKA, Germany) for 3 minutes, and the milky emulsion was prepared. The emulsion was separated by device and the kerosene was collected below, the separation efficiency ( E ff , %) and flux were calculated according to equations ( 2 ) and ( 3 ) respectively: $$\:{E}_{ff}=(1-\frac{{C}_{0}}{{C}_{1}})\times\:100\%$$ 2 Where C 0 and C 1 were the water content in oil after and before separation tested by the Karl Fischer method automatic micro moisture tester (Huakun, Shandong). $$\:Flux=\frac{V}{S\ast\:T}$$ 3 Where V was the oil volume of downstream (L), S was the effective area (m 2 ), and T was separation time (h). 3. Result and discussion 3.1. Preparation of carbon paper The preparation of carbon paper consisted of two steps, firstly, mixed micro glass fiber and unbleached Kraft pulp together and made base paper by wet-end papermaking technology, then the base paper was pyrolyzed at 800 ºC for 2 hours under N 2 atmosphere, the obtained carbon paper was named as MxWy, where x and y represented the content of micro glass fiber and Kraft pulp respectively. As shown in Fig. 2 (A) , the size of the original yellowish base paper was 4*4 cm 2 , however, after the carbonization process, all the carbon paper turned black, and the size of the carbon paper was reduced. From Fig. 2 (B) we can see that sample M0W100 with only wood pulp, has shrunk to around 3*3 cm 2 , and the size of sample M70W30 shrank only by 0.3 cm, which indicated that micro glass fiber helped reduce the size shrinkage of carbon paper. Because, during carbonization, the wood fiber shrinkage was inevitable, Han et al. ( 2016 ) studied the carbonized aerogel size made of waste newspaper decreased from 35.46 mm to 26.23 mm. Jiao et al. ( 2016 ) found that the average diameter of carbonized bamboo pulp fibers decreased from 15.33 µm to 6.02 µm. Meanwhile, the carbon paper with only wood pulp was fragile and limited its application, fortunately, the carbon paper of M70W30 was flexible, as shown in Fig. 2 (C) . Pore size, internal pores structure and porosity were used to judge the properties of filter materials (Xu et al., 2023 ). Porosity and internal pores structure determined the dust hold capacity of the filter medium (Bae et al., 2023 ). Pore size and pore structure can determine the size of trapped particles and determine the accuracy of the filter medium (Ling et al., 2023 ). As can be seen from Table 1 , after carbonization, both the maximum and minimum pore diameter of carbon paper were reduced. Because the diameter of wood pulp fiber was reduced after carbonization at high temperatures, resulting in the size shrinkage of the base paper. Due to the addition of 70% micro glass fiber, more holes were generated in the shrinkage process of wood pulp. The number of pores of the carbon paper M70W30 increased by 72%, while the porosity also increased by 40% compared with base paper. Since the average diameter of micro glass fiber and unbleached Kraft pulp fiber was 2.44 µm and 30 µm respectively, it was found that comparing the pore size data of carbon paper that with the increase of micro glass fiber content, the maximum pore size, minimum pore size and average pore size of carbon paper all decreased, however, the number of pores and porosity were increased. Table 1 Analysis of pore structure of base paper and carbon paper. Sample Maximum pore size (µm) Mean pore size (µm) Minimum Pore size (µm) Number of pores (*10 6 ) Porosity (%) Base paper M70W30 9.57 5.02 1.73 3.18 64.27 Carbon paper M70W30 7.63 4.51 1.15 5.46 90.22 Carbon paper M50W50 10.32 5.22 1.19 3.29 73.53 Carbon paper M30W70 12.84 6.09 1.27 2.11 63.57 3.2. SEM and EDS analysis SEM and EDS were used to explore the morphology and surface chemical composition changes of M70W30 base paper and carbon paper before and after carbonization. Figure 3 (A, B) showed that the SEM images of both base paper and carbon paper were interlaced and porous structures. EDS measured that the content of C and O elements in the base paper is 35.43% and 35.88% respectively, while the content of C and O of carbon paper was 58.68% and 19.60% respectively, indicating that the content of C was significantly increased, and most oxygen-containing groups were damaged during pyrolysis treatment. After carbonization, the diameter of the wood pulp fiber of carbon paper shrunk and became wrinkled (Fig. 3 C), because of the different shrinkage rates between the surface and the internal structure of the wood pulp fiber during carbonization (Ma et al., 2023 ). Many studies have shown that micron-scale roughness makes the material superhydrophobic (Piedrahita et al., 2024 ) However, the micro glass fiber was not affected by high temperature, and the surface did not change significantly Fig. 3 D. Figure 2 B shows that the size of the carbon paper of M70W30 was smaller and became more compact. The base weight of carbon paper M70W30 was 74.7 g/m 2 , which was 25.3% lower than base paper. 3.3. XRD analysis XRD was conducted on base paper and carbon paper of M70W30 to check the structure changes after carbonization. As can be seen from Fig. 4 , there were significant differences after carbonization. The typical signal peaks of base paper were 2θ ≈ 16.18 ° and 22.68 º, which were derived from the mixture of the (101) and (10ī) crystal plane and the (002) crystal plane of cellulose (Nishiyama et al., 2002 ). After carbonization, the peak of cellulose completely disappears, indicating that the crystallization region of cellulose has been completely destroyed. The (002) crystalline plane of graphitized carbon (Cheng et al., 2016 ) was formed at 2θ ≈ 26.30 º. According to the formula d 002 = nγ/2sinθ 002 , g=(0.3440-d 002 )/(0.3440 − 0.3354) , where d 002 was the layer spacing between graphite crystals, γ was the wavelength of X-ray, 0.15406 nm, θ 002 = 13.15 º, g was the degree of graphitization, after calculation, the degree of carbonization of M70W30 carbon paper was 63%. 3.4. TGA analysis TGA was analyzed to investigate the thermal stability of base paper and carbon paper, the result was shown in Fig. 5 . The base paper was containing 70% micro glass fiber and 30% unbleached Kraft pulp, the thermo gravimetric process of the base paper went through two stages: the loss of water and the degradation of cellulose, the temperature at maximum weight loss was 361°C. When the temperature rose to 800°C, the mass loss was about 29%. The residue without thermal decomposition was mainly micro glass fiber because the main component was silica, which had good heat resistance. Obviously, the mass loss of carbon paper was only 1.2% during heating from 20°C to 800°C, indicating that the carbon paper contained only a small amount of water vapor absorbed from the air, which also proved that the structure of carbon paper has undergone a great change, with a large reduction of oxygen groups. 3.5. XPS analysis XPS can analyze the chemical composition with higher resolution. As can be seen from Fig. 6 (A) , Si 2p and Si 2s were marked at 102 eV and 153 eV, C 1s was at 284 eV and O 1s was at 531 eV respectively in the full scan spectra of base paper and carbon paper of 0 ~ 600 eV. The content of C and O of base paper M70W30 was 51.85% and 38.32%. After carbonization, the content of C and O of carbon paper M70W30 was 57.68% and 32.92%. After carbonization, the O content in the base paper decreased, so the ratio of C/O increased from 1.35 to 1.75, implying that oxygen-containing groups were destroyed during pyrolyze treatment. Figure 6 (B, C) showed high resolution base paper and carbon paper O 1s spectrum, the three obvious peaks at 531.1, 532.1 and 533.1 eV represented the carbonyl group C = O, the phenolic hydroxyl Ar-OH and C-O (C-OH, C-O-C, O = C-OR) groups (Ma et al., 2016 ; Ishimaru et al., 2007 ), respectively. In Fig. 5 (D), the deconvoluted C 1s spectrum of base paper revealed four peaks at 284.6eV (C-C/C = C, 33.83%), 285.2 eV (C-O, 12.33%), 286.37 eV (C = O, 53.24%) and 289.2 eV (O = C-O, 0.60%). After carbonization, the chemical composition of C in carbon paper has changed. As seen in Fig. 5 (E), the main peak was sp 2 hybrid graphitized C at 284.6eV (C-C/C = C) (Chen et al., 2014 ). 3.6. Wettability analysis Figure 7 (A) showed that water droplets (dyed with methyl blue) and kerosene was base paper were quickly absorbed by the base paper with a water contact angle of 0 º, indicating that base paper was hydrophilic and oleophilic in the air because of hydroxyl groups (Yang et al., 2023 ). In general, the surface wettability of hydrophobic oil-water separation materials was constructed by chemicals modification, while carbon paper was prepared by one-step carbonization from base paper (Zheng et al., 2022 ). Figure 7 (B) demonstrated water droplets were present in spherical shape on the carbon paper surface with a water contact angle of 140 ºC, which performed highly hydrophobic, kerosene was quickly absorbed by carbon paper, and the carbon paper has hydrophobic and oleophilic in the air. Put base paper in kerosene, then add the water, parts of the water slid away, but the base paper was dyed blue, as shown in Fig. 7 (C) , suggesting that base paper was hydrophilic in the oil phase and can be polluted by water. When carbon paper was in kerosene, when water flowed through carbon paper, carbon paper was not contaminated by water, as shown in Fig. 7 (D) . Thus, the carbon paper was highly hydrophobic in oil. To verify the antifouling performance, carbon paper was dropped into the mixture of kerosene and water, as shown in Fig. 7 (E) , carbon paper descended slowly and lodged between the oil phase and water phase interface, using external force pressed carbon paper to the water phase, when loosed the tweezers, carbon paper floated back to interface soon, took out the carbon paper and found that there was no blue water on the surface, it showed that the carbon paper in the oil phase had the good self-cleaning capacity and pollution prevention performance. 3.7. Oil-water separation performance of carbon paper 3.7.1. Separation of slick oil Oil and water exist in various forms, mainly including floating oil, emulsified oil and dissolved oil (Huang et al., 2024 ). The separation of oil slick and emulsified oil is a focus of oil water separation research. The thickness of M70W30 carbon paper was about 0.32 mm, which was suitable to be used as a filter layer to separate oil slick and emulsified oil by separation device in the laboratory. Mixed 10 mL of dichloromethane and 10 mL of water, stirred and poured into the separation device. Carbon paper was sandwiched in the middle with an effective area of about 1.76 cm 2 , as shown in Fig. 8 (A) . When the mixture was transferred to the carbon paper, the blue water phase touched the carbon paper first, followed by the oil phase due to the density difference. Carbon paper was hydrophobic in air and oil. The water phase was repelled, while the oil phase can pass through smoothly. When the separation was completed, the oil phase completely entered the receiving bottle, and the water phase stayed above the carbon paper. Carbon paper also showed good separation efficiency on light density oil and water mixtures such as kerosene, n-hexane, and engine oil. As shown in Fig. 8 (B) , the separation efficiency of light oil and heavy oil was all above 99%. In order to explore the reuse performance of carbon paper, after the separation of dichloromethane and water mixture, the carbon paper was washed with methanol and dried in air, after 5 cycles of testing, the results as shown in Fig. 8 (C) , the separation performance showed good stability with efficiency more above 99%, and the flux 2600 ~ 3400 L/m 2 ·h. The M70W30 carbon paper was compared with the oil-water separation materials published in recent years, as shown in Table 2 . It was found that the membrane had high separation flux and high separation efficiency. Table 2 Materials previously reported for water/oil mixture separation are summarized. Samples WCA (°) Separation Pressure Flux (L·m 2 ·h − 1 ) Efficiency (%) Ref. SA-NiCo-CH@Al 2 SiO 5 FP 153 Gravity 400–7000 95.4 Chen et al., 2021 PDMS/UiO-66-NH 2 @CP 162 Gravity 100–500 98 Chen et al., 2024 PF@PDA/BaSO4 156 Gravity 500–600 99 Yang et al., 2020 Poly(DR-DMP)@HAP fabric 162 Gravity 8000–9000 97 Wang et al., 2024 DTS@paper 165 Gravity 500–600 94–96 Yang et al., 2023 EP@PDMS@Fe 3 O 4 @SiO 2 @PP 155 Gravity 40–130 98 Li et al., 2022 M70W30 carbon paper 140 Gravity 2600–3400 99 This work 3.7.2. Separation of emulsified oil Due to the good stability of emulsified water (Zhang et al., 2023 ) and its size usually less than 20 µm in diameter (Ge et al., 2018 ), water-in-oil emulsion was covered by oil film and has lower surface tension, which impeded the aggregation of water droplets (Wang et al., 2024 ). In this experiment, stable emulsion was prepared under high speed dispersive agitation. M70W30 carbon paper was used to separate the emulsion, successfully separating emulsified water only under gravity, separation efficiency reached 98.5%, and flux reached 1200 L/m 2 ·h, which was higher than the usual cellulose-based separation media, due to the higher porosity of carbon paper. Figure 9 (A) showed that the appearance of emulsified oil was a milky solution, the particle diameter of the original emulsion with a wider droplet size distribution under the optical electron microscope, the average diameter was 959 nm measured by laser particle size analyzer. After separation, as shown in Fig. 9 (B) , kerosene became clear and transparent, no emulsified particles were observed by the optical electron microscope, and the average diameter was 1.1 nm measured by a laser particle size analyzer. Figure 9 (C) depicts the separation mechanism of emulsion separation. The droplets of emulsion were captured by the micro glass fiber in the form of coalescence, the adjacent emulsion droplets squeezed and collided on the carbon paper and then flocculated into large droplets, the large droplets were released and separated from the carbon paper and achieved oil water separation (Li et al., 2023 ). When the emulsion was close to the filter material, the capture efficiency depended on the fiber diameter, the diameter of the emulsion droplet and the flow rate. In this experiment, the emulsion particles were captured by the labyrinth structure of carbon paper, after being squeezed and collided, the emulsion droplets accumulated into large particles. The mean pore size of carbon paper was measured as 4.51 µm, which could guarantee the efficient emulsion breaking, besides, the released water was gathered above while the oil passed through the carbon paper. 4. Conclusions In this paper, unbleached sulfated coniferous wood pulp and microglass fibers were used as raw materials, and the wet papermaking technology was used to produce. The paper was obtained by high temperature carbonization with different sizes of carbon paper. When the content of microglass fiber was 70%, the carbon paper had better toughness, with an average pore size of 4.51µm and a porosity of 90.22%. After high-temperature carbonization, the carbon paper has high thermal stability, a water contact angle of 140º in the air, and also exhibits high hydrophobicity and anti-pollution properties in the oil phase. Water-oil separation experiments on M70W30 carbon paper showed that the separation efficiency of this material for oil-water mixtures reached more than 99%, and that for water-in-oil emulsions reached 98.5%, which was higher than the separation performance of cellulose-based filter paper. Therefore, carbon paper is a potential effective filter material for separating floating oil and emulsified oil. Declarations Conflict of interest The authors declare that there are no conflicts of interest related to the publication of this article in this journal. Ethical approval This article does not include any studies conducted by any of the authors on either humans or animals. We did not gather any specimens of both humans and animals. Ethical standards This study was carried out based on Compliance with Ethical Standards. Clinical trial number Not applicable. Consent for publication Not applicable. Funding The National Key Research and Development Program of China (No.2022YFC2105503). Author Contribution Qian Yang: Methodology, Investigation, Formal analysis. Mingyue Zhao: Investigation, Formal analysis, Writing-original draft. Lanfeng Hui: Conceptualization, Funding acquisition, Writing-review & editing. Jieting Xin and Tingting Zhang: Test and Data. 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Appl Surf Sci 659:159700. https://doi.org/10.1016/j.apsusc.2024.159700 Soffer A, Gilron J, Saguee S et al (1999) U.S. Patent No. 5,925,591. Washington, DC: U.S. Patent and Trademark Office. Teng Y, Shi B, Zhang J (2020) Preparation of robust superhydrophobic paper by roll coating with modified micro/nano SiO 2 . Chem Lett 49:1095-1098. https://doi.org/10.1246/cl.200381 Wahid F, Zhao XJ, Duan Y (2021) Designing of bacterial cellulose-based superhydrophilic/underwater superoleophobic membrane for oil/water separation. Carbohydr Polym 257:117611. https://doi.org/10.1016/j.carbpol.2020.117611 Wang G, He Y, Wang H (2015) A cellulose sponge with robust superhydrophilicity and under-water superoleophobicity for highly effective oil/water separation. Green Chem 17:3093-3099. https://doi.org/10.1039/c5gc00025d Wang W, Chen C, Li Z (2024) A novel superhydrophobic cotton fabric constructed by rosin-based polymer and nano-hydroxyapatite for oil/water separation. Sep Purif Technol 349:127847. https://doi.org/10.1016/j.seppur.2024.127847 Wang Z, Cui Z, Qi X (2024) Constructing superhydrophilic/superhydrophobic Janus membrane assisted by dual-interface-confined strategy for on-demand oil-in-water and water-in-oil emulsions separation. Sep Purif Technol 350:127846. https://doi.org/10.1016/j.seppur.2024.127846 Xian Z, Du Z, Chen Y (2023) Dynamic contact angle measurement of hydrophilic open microchannels: The role of surface wettability. Phys Fluids 35:092110. https://doi.org/10.1063/5.0169449 Xu H, Zhang Z, Jiang (2024) Multifunctional amphibious superhydrophilic-oleophobic cellulose nanofiber aerogels for oil and water purification. Carbohydr Polym 330:121774. https://doi.org/10.1016/j.carbpol.2023.121774 Xu T, Shi L, Shao S (2023) Dynamic pore modulation of contracted carbon fiber filter for wastewater treatment: Filtration performance and in-situ regeneration mechanism. Chem Eng J 473:145243. https://doi.org/10.1016/j.cej.2023.145243 Yang G, Wang M (2023) Surface roughness effect on dynamic wettability in imbibition process. Comput Fluids 263:105959. https://doi.org/10.1016/j.compfluid.2023.105959 Yang J, Xie A, Cui J (2020) An acid-alkali-salt resistant cellulose membrane by rapidly depositing polydopamine and assembling BaSO4 nanosheets for oil/water separation. Cellulose 27:5169-5178. https://doi.org/ 10.1007/s10570-020-03114-9 Yang Y, Zhao X, Ye L (2023) Facile construction of durable superhydrophobic cellulose paper for oil-water separation. Cellulose 30:3255-3265. https://doi.org/10.1007/s10570-023-05074-2 Zhang M, Fan L, Liu Y, Li J (2023) Effects of interface generation, droplet size and antioxidant partitioning on the oxidation rate and oxidative stability of water-in-oil emulsions: A comparison of coarse emulsions and nanoemulsions. Food Hydrocolloids 136:108227. https://doi.org/10.1016/j.foodhyd.2022.108227 Zhao M, Hui L, Gao Y (2024) Electrospun PVDF-based cellulose stearoyl ester nanocomposites for effective separation of water-in-oil emulsions. Ind Crops Prod 210:118140. https://doi.org/10.1016/j.indcrop.2024.118140 Zheng G, Kang X, Ye H (2023) Recent advances in functional utilisation of environmentally friendly and recyclable high-performance green biocomposites: A review. Chin Chem Lett 35:108817. https://doi.org/10.1016/j.cclet.2023.108817 Zheng X, Ji B, Jiang et al (2022) Polydimethylsiloxane/carbonized bacterial cellulose sponge for oil/water separation. Process Saf Environ Prot 165:173-180. https://doi.org/10.1016/j.psep.2022.07.014 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 17 Feb, 2025 Read the published version in Cellulose → Version 1 posted Editorial decision: Revision requested 12 Oct, 2024 Editor assigned by journal 12 Oct, 2024 Submission checks completed at journal 29 Sep, 2024 First submitted to journal 13 Sep, 2024 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5086335","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":365289220,"identity":"3421872a-ce26-485b-8ca3-4b72d2aa79d5","order_by":0,"name":"Qian Yang","email":"","orcid":"","institution":"Tianjin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Qian","middleName":"","lastName":"Yang","suffix":""},{"id":365289221,"identity":"2172efb3-95ee-441a-9a30-9161d984602d","order_by":1,"name":"Mingyue Zhao","email":"","orcid":"","institution":"Tianjin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Mingyue","middleName":"","lastName":"Zhao","suffix":""},{"id":365289222,"identity":"b560ba93-eec9-48bd-99cd-209f4e1a3a20","order_by":2,"name":"Lanfeng Hui","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAr0lEQVRIiWNgGAWjYBACAwbGBiCVIMfG3n6ANC3GfDxnEojVAgYJifMkHAyI02Iukdz24ENNWnqbBEMCw4+KbYS1WM5IbDeccSwnt0268QBjz5nbRDjsRmKbNA9bRW6bzIEEZsY2YrX8+VeRziaRYECCFsa2nAQStJx52G7Y25dm2AYM5IPE+eV4+rMHP74ly8u3tx988KOCCC1AwAZnHSBKPYqWUTAKRsEoGAVYAQDekj3RWr+w2AAAAABJRU5ErkJggg==","orcid":"","institution":"Tianjin University of Science and Technology","correspondingAuthor":true,"prefix":"","firstName":"Lanfeng","middleName":"","lastName":"Hui","suffix":""},{"id":365289223,"identity":"adb0e908-9b89-4790-bb2e-d7c463533515","order_by":3,"name":"Jieting Xin","email":"","orcid":"","institution":"Tianjin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Jieting","middleName":"","lastName":"Xin","suffix":""},{"id":365289224,"identity":"4bf182fa-cfb8-459f-87bf-0206cfd14b1f","order_by":4,"name":"Tingting Zhang","email":"","orcid":"","institution":"Tianjin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Tingting","middleName":"","lastName":"Zhang","suffix":""},{"id":365289225,"identity":"059062b0-edf5-44a8-a61e-1573aa9504bf","order_by":5,"name":"Zhong Liu","email":"","orcid":"","institution":"Tianjin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Zhong","middleName":"","lastName":"Liu","suffix":""},{"id":365289226,"identity":"e741d736-8092-455f-8d9b-58c4c8e84467","order_by":6,"name":"Jiayan Li","email":"","orcid":"","institution":"Tianjin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Jiayan","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2024-09-14 01:14:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5086335/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5086335/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10570-025-06402-4","type":"published","date":"2025-02-17T15:57:27+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":70547085,"identity":"d7546902-fb4f-4020-81dc-36e2460c8526","added_by":"auto","created_at":"2024-12-04 09:29:43","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":157548,"visible":true,"origin":"","legend":"\u003cp\u003ePreparation schematic of hydrophobic carbon paper\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/1b0fbe0ae6396c964dd421fc.png"},{"id":70547439,"identity":"00eaff3f-69ad-4e27-abb6-04cdcd2477e7","added_by":"auto","created_at":"2024-12-04 09:37:43","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":239502,"visible":true,"origin":"","legend":"\u003cp\u003eThe size of (A) base paper, (B) carbon paper; and (C) flexibility of carbon paper M70W30.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/4fe94325c7047d4c68e748b7.png"},{"id":70547089,"identity":"42ca5053-bafb-4588-8e58-b35bcab24824","added_by":"auto","created_at":"2024-12-04 09:29:43","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":354402,"visible":true,"origin":"","legend":"\u003cp\u003e(A) and (B) are SEM and EDS of base paper and carbon paper, respectively; (C) and (D) are SEM of wood pulp and micro glass fiber after carbonized.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/7393f4a5731d6e0a0b1cb37f.png"},{"id":70547091,"identity":"db7b4523-90c2-4912-b62b-63f006936f3e","added_by":"auto","created_at":"2024-12-04 09:29:43","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":492007,"visible":true,"origin":"","legend":"\u003cp\u003eXRD spectra of base paper and carbon paper\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/d3adc853f99528da5e174e5b.png"},{"id":70548958,"identity":"76f804a6-a936-49c4-ae36-e71d258a817c","added_by":"auto","created_at":"2024-12-04 09:45:43","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":254613,"visible":true,"origin":"","legend":"\u003cp\u003eThermo gravimetric change of base paper and carbon paper\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/ca5507b5a38c65c5a588f886.png"},{"id":70547086,"identity":"6705eef7-3fb2-4284-b986-eb531ea18f45","added_by":"auto","created_at":"2024-12-04 09:29:43","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":150615,"visible":true,"origin":"","legend":"\u003cp\u003e(A) is XPS spectra of base paper and carbon paper, (B, C) is O 1s high-resolution XPS spectra, and (D, E) is C 1s high-resolution XPS spectra of base paper and carbon paper.\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/a428a785f31bdb1da3cd8820.png"},{"id":70547087,"identity":"cf9acc04-d326-463d-867c-b55b171f2240","added_by":"auto","created_at":"2024-12-04 09:29:43","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":494543,"visible":true,"origin":"","legend":"\u003cp\u003e(A, B) Surface wettability of base paper and carbon paper, (C) hydrophilic of base paper in oil, (D) hydrophobic of carbon paper in oil, (E) antifouling test of carbon paper.\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/02ce54813582afaab42f51cf.png"},{"id":70547442,"identity":"fd155325-7815-42ad-96fc-8a208eeea0cb","added_by":"auto","created_at":"2024-12-04 09:37:43","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":331444,"visible":true,"origin":"","legend":"\u003cp\u003e(A) diagram of the separation process of oil slick of carbon paper, (B) separation efficiency of various oils, and (C) the influence of recycling on separation efficiency and flux.\u003c/p\u003e","description":"","filename":"floatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/f754e7dab0c0053fc6ee9d44.png"},{"id":70547440,"identity":"d8c7ace3-a528-4ffb-93b1-55fa52fa0d6e","added_by":"auto","created_at":"2024-12-04 09:37:43","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":475200,"visible":true,"origin":"","legend":"\u003cp\u003eDiagram of the separation process of emulsified oil. (A, B) photos before and after separation, optical microscope pictures and particle size distribution of emulsions and (C) mechanism of emulsion separation.\u003c/p\u003e","description":"","filename":"floatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/a50455d2ddb19c9a82f9c59e.png"},{"id":77052744,"identity":"01b33736-063a-4da6-988f-680940f15a5f","added_by":"auto","created_at":"2025-02-24 16:24:19","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3808750,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5086335/v1/21f81643-f83c-4ebf-9808-4ad4491a0124.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Chemical free and hydrophobic carbon paper for effective separation emulsified oil/water mixture based on cellulose and micro glass fiber","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eFuel oil and organic solvents are important resources for human life, if they are mixed with water due to unexpected circumstances will cause a waste of resources. According to the existing form of oil/water mixture, oily sewage can be divided into an oil-water incompatible mixture (oil slick), unstable dispersed phase and stable emulsion (Abuhantash et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Among them, the separation of the oil slick is relatively simple, because there is a density difference, and easy to divide into two layers, the appropriate selection of \u0026ldquo;water removing type\u0026rdquo; (Teng et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Zhao et al, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2024\u003c/span\u003e) or \u0026ldquo;oil moving type\u0026rdquo; (Xu et al., \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Wahid et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) materials can effectively separate useful oils from the harmful mixture. The separation of the emulsified oil-water mixture is still full of challenges because emulsions have good stability and smaller diameters (less than 20 \u0026micro;m).\u003c/p\u003e \u003cp\u003eTraditionally, chemical or flotation demulsification methods are used but gradually restricted or even prohibited due to low efficiency and high energy consumption. Currently, materials with special wetted surfaces were introduced to separate emulsified oil/water mixture, the main factors affecting the surface wettability were surface free energy and surface geometrical structure (Yang et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Xian et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). At present, silicon (Han et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2024\u003c/span\u003e) or fluorine (He et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2024\u003c/span\u003e) based chemicals are used to reduce the surface free energy, which is usually expensive and causes secondary pollution (Bai et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Li et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Zheng et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Therefore, the development of environmentally friendly and reliable oil/water separation materials without the use of chemicals has become a hot research and development. Additionally, the pore size of normal separation materials is too big to separate the emulsified mixture (Firmanda et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Peng et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Lang et al., \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Wang et al. (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2015\u003c/span\u003e) designed two layers of superhydrophilic sponge, the separation efficiency of the micrometer porous layer is much lower than the nanometer porous layer, which indicated that the pore size was particularly important for the separation efficiency of emulsified oil/water mixture.\u003c/p\u003e \u003cp\u003eSoffer et al. (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e1999\u003c/span\u003e) applied for the patent of cellulose carbonization, in the process of carbonization, cellulose was depolymerized into monosaccharides, then formed condensed aromatic structures and released gases containing non-carbon atoms (Kawamoto et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2003\u003c/span\u003e). Cellulose based carbon aerogel has a large specific surface area and porosity, low density, lightweight, flame retardant and conductive, and more importantly, its surface is oleophilic and hydrophobic in the absence of chemicals (Dong et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2021\u003c/span\u003e: Lang et al., \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), therefore, the separation of an oil-water mixture by carbon aerogel has become a hot research topic in recent years. Han et al. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) prepared hydrophobic porous carbon aerogel from waste newspaper via the process of freeze-drying and carbonization for organic pollution control. However, the production process of carbon aerogel is complex, because freeze drying is time-consuming and has high energy consumption. Besides, during the carbonization, the product shrunk as high as more than half (Jiao et al., \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2016\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn this experiment, unbleached kraft pulp and micro glass fiber were used as the raw materials to prepare the base paper with porous structure by the wet-end papermaking method, and then the carbon paper with porosity of 90.22% was obtained by the carbonization process under N\u003csub\u003e2\u003c/sub\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The carbon paper was hydrophobic and oleophilic, and the water contact angle reached 140 \u0026ordm;, which could be hydrophobic in both air and oil. The thickness was only 0.32 mm, and the separation efficiency of the oil slick and emulsified oil were more than 99% and 98.5% respectively only under gravity.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"2. Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Materials\u003c/h2\u003e \u003cp\u003eUnbleached Kraft pulp was obtained from Shandong Huatai Group with beating degree of 33\u0026ordm;SR. Micro glass fiber was purchased from Unifrax (Shanghai) Co., LTD, diameter of 2.44 \u0026micro;m. High purity nitrogen was purchased from Tianjin Junliang City Changfu Gas Co., LTD., with a purity of 99.999%. Other chemicals were obtained from local suppliers and used as received.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Preparation of base paper\u003c/h2\u003e \u003cp\u003eMicro glass fiber was dispersed in pH\u0026thinsp;=\u0026thinsp;4.6 solution at 600 rpm for 5 min, unbleached Kraft pulp was dispersed in a fiber standard dissociator (L\u0026amp;W, Sweden) for 10000 r. Mixed the dispersed micro glass fiber with the pulp solution (pulp suspensions), and stirred for 5000 r, the mixture was well dispersed and made 100 g/m\u003csup\u003e2\u003c/sup\u003e base weight base paper by hand sheet former machine (PTI, Austria).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Preparation of carbon paper\u003c/h2\u003e \u003cp\u003eThe base paper was cut into 4 cm squares, and the carbonization process was carried out in a tubular furnace. Before the pyrolysis treatment, displacing the air in the furnace with N\u003csub\u003e2\u003c/sub\u003e, the sample was heated to 150 \u0026ordm;C at a heating rate of 10 \u0026ordm;C/min and maintained for 60 min, then heated to 450 \u0026ordm;C at a heating rate of 5 \u0026ordm;C/min and maintained for 60 min, finally heated to 800 \u0026ordm;C at a heating rate of 3 \u0026ordm;C/min and maintained for 120 min. Stopping heating, and the temperature was self cooled to room temperature under the protection of N\u003csub\u003e2\u003c/sub\u003e, the carbon paper was obtained.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4. Characterization\u003c/h2\u003e \u003cp\u003eThe maximum pore size, mean pore size, minimum pore size, number of pores and porosity of samples (diameter 15 mm) were tested by capillary pore diameter measuring instrument (Quantachrome, America). Surface morphologies were investigated by scanning electron microscopy (SEM, Hitachi, Japan). Energy disperse spectroscopy (EDS) was measured by X-Max\u003csup\u003eN\u003c/sup\u003e (Oxford Instruments, British). The crystal structures were tested at a scan rate of 4 \u0026ordm;/min from 10 to 40 \u0026ordm; by X-ray diffractometer (XRD, Rigaku, Japan). X-ray photoelectron spectroscopy data was recorded using EscaLab 250Xi (XPS, Thermo Fisher, America). Water contact angle (WCA) was measured with 3 \u0026micro;L of deionized water by a dynamic contact angle measuring instrument PGX (Fibro, Sweden). Thermo gravimetric analysis (TGA) was conducted by TGA-50 (Shimadzu, Japan) with a heating rate of 20 \u0026ordm;C min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e to 800 \u0026ordm;C under N\u003csub\u003e2\u003c/sub\u003e atmosphere.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.5. Oil/water mixture separation\u003c/h2\u003e \u003cp\u003eOil slick: 10 mL of dichloromethane (dye with Sudan red) and 10 mL of water (dyed with methyl blue) were mixed and stirred, the carbon paper (area 1.76 cm\u003csup\u003e2\u003c/sup\u003e) was fixed in the separation device and the oil/water mixture was poured above, water was repelled on the carbon paper and dichloromethane was collected below, the separation efficiency (\u003cem\u003eE\u003c/em\u003e\u003csub\u003e\u003cem\u003eff\u003c/em\u003e\u003c/sub\u003e, %) was calculated according to the equation:\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ1\" name=\"EquationSource\"\u003e\n$$\\:{E}_{ff}={v}_{1}/10\\ast\\:100\\%$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e1\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{v}_{1}\\)\u003c/span\u003e\u003c/span\u003e represented the volume of collected dichloromethane.\u003c/p\u003e \u003cp\u003eEmulsified oil: Mixed kerosene and water with a volume ratio of 99:1, the mixture was dispersed by high speed dispersing machine T18 (IKA, Germany) for 3 minutes, and the milky emulsion was prepared. The emulsion was separated by device and the kerosene was collected below, the separation efficiency (\u003cem\u003eE\u003c/em\u003e\u003csub\u003e\u003cem\u003eff\u003c/em\u003e\u003c/sub\u003e, %) and \u003cem\u003eflux\u003c/em\u003e were calculated according to equations (\u003cspan refid=\"Equ2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) and (\u003cspan refid=\"Equ3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) respectively:\u003cdiv id=\"Equ2\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ2\" name=\"EquationSource\"\u003e\n$$\\:{E}_{ff}=(1-\\frac{{C}_{0}}{{C}_{1}})\\times\\:100\\%$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e2\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sub\u003e and \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sub\u003e were the water content in oil after and before separation tested by the Karl Fischer method automatic micro moisture tester (Huakun, Shandong).\u003cdiv id=\"Equ3\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ3\" name=\"EquationSource\"\u003e\n$$\\:Flux=\\frac{V}{S\\ast\\:T}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e3\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere \u003cem\u003eV\u003c/em\u003e was the oil volume of downstream (L), \u003cem\u003eS\u003c/em\u003e was the effective area (m\u003csup\u003e2\u003c/sup\u003e), and \u003cem\u003eT\u003c/em\u003e was separation time (h).\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Result and discussion","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.1. Preparation of carbon paper\u003c/h2\u003e \u003cp\u003eThe preparation of carbon paper consisted of two steps, firstly, mixed micro glass fiber and unbleached Kraft pulp together and made base paper by wet-end papermaking technology, then the base paper was pyrolyzed at 800 \u0026ordm;C for 2 hours under N\u003csub\u003e2\u003c/sub\u003e atmosphere, the obtained carbon paper was named as MxWy, where x and y represented the content of micro glass fiber and Kraft pulp respectively.\u003c/p\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cb\u003e(A)\u003c/b\u003e, the size of the original yellowish base paper was 4*4 cm\u003csup\u003e2\u003c/sup\u003e, however, after the carbonization process, all the carbon paper turned black, and the size of the carbon paper was reduced. From Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cb\u003e(B)\u003c/b\u003e we can see that sample M0W100 with only wood pulp, has shrunk to around 3*3 cm\u003csup\u003e2\u003c/sup\u003e, and the size of sample M70W30 shrank only by 0.3 cm, which indicated that micro glass fiber helped reduce the size shrinkage of carbon paper. Because, during carbonization, the wood fiber shrinkage was inevitable, Han et al. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) studied the carbonized aerogel size made of waste newspaper decreased from 35.46 mm to 26.23 mm. Jiao et al. (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) found that the average diameter of carbonized bamboo pulp fibers decreased from 15.33 \u0026micro;m to 6.02 \u0026micro;m. Meanwhile, the carbon paper with only wood pulp was fragile and limited its application, fortunately, the carbon paper of M70W30 was flexible, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cb\u003e(C)\u003c/b\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003ePore size, internal pores structure and porosity were used to judge the properties of filter materials (Xu et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Porosity and internal pores structure determined the dust hold capacity of the filter medium (Bae et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Pore size and pore structure can determine the size of trapped particles and determine the accuracy of the filter medium (Ling et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). As can be seen from Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, after carbonization, both the maximum and minimum pore diameter of carbon paper were reduced. Because the diameter of wood pulp fiber was reduced after carbonization at high temperatures, resulting in the size shrinkage of the base paper. Due to the addition of 70% micro glass fiber, more holes were generated in the shrinkage process of wood pulp. The number of pores of the carbon paper M70W30 increased by 72%, while the porosity also increased by 40% compared with base paper.\u003c/p\u003e \u003cp\u003eSince the average diameter of micro glass fiber and unbleached Kraft pulp fiber was 2.44 \u0026micro;m and 30 \u0026micro;m respectively, it was found that comparing the pore size data of carbon paper that with the increase of micro glass fiber content, the maximum pore size, minimum pore size and average pore size of carbon paper all decreased, however, the number of pores and porosity were increased.\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\u003eAnalysis of pore structure of base paper and carbon paper.\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=\"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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSample\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eMaximum pore size (\u0026micro;m)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean pore size (\u0026micro;m)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMinimum Pore size (\u0026micro;m)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNumber of pores (*10\u003csup\u003e6\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003ePorosity (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBase paper M70W30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e5.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e64.27\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarbon paper M70W30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e4.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e90.22\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarbon paper M50W50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e5.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e73.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarbon paper M30W70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e6.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e63.57\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=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.2. SEM and EDS analysis\u003c/h2\u003e \u003cp\u003eSEM and EDS were used to explore the morphology and surface chemical composition changes of M70W30 base paper and carbon paper before and after carbonization. Figure\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e\u003cb\u003e(A, B)\u003c/b\u003e showed that the SEM images of both base paper and carbon paper were interlaced and porous structures. EDS measured that the content of C and O elements in the base paper is 35.43% and 35.88% respectively, while the content of C and O of carbon paper was 58.68% and 19.60% respectively, indicating that the content of C was significantly increased, and most oxygen-containing groups were damaged during pyrolysis treatment. After carbonization, the diameter of the wood pulp fiber of carbon paper shrunk and became wrinkled (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eC), because of the different shrinkage rates between the surface and the internal structure of the wood pulp fiber during carbonization (Ma et al., \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Many studies have shown that micron-scale roughness makes the material superhydrophobic (Piedrahita et al., \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2024\u003c/span\u003e) However, the micro glass fiber was not affected by high temperature, and the surface did not change significantly Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eD. Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB shows that the size of the carbon paper of M70W30 was smaller and became more compact. The base weight of carbon paper M70W30 was 74.7 g/m\u003csup\u003e2\u003c/sup\u003e, which was 25.3% lower than base paper.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.3. XRD analysis\u003c/h2\u003e \u003cp\u003eXRD was conducted on base paper and carbon paper of M70W30 to check the structure changes after carbonization. As can be seen from Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, there were significant differences after carbonization. The typical signal peaks of base paper were 2θ\u0026thinsp;\u0026asymp;\u0026thinsp;16.18 \u0026deg; and 22.68 \u0026ordm;, which were derived from the mixture of the (101) and (10ī) crystal plane and the (002) crystal plane of cellulose (Nishiyama et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2002\u003c/span\u003e). After carbonization, the peak of cellulose completely disappears, indicating that the crystallization region of cellulose has been completely destroyed. The (002) crystalline plane of graphitized carbon (Cheng et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) was formed at 2θ\u0026thinsp;\u0026asymp;\u0026thinsp;26.30 \u0026ordm;. According to the formula \u003cem\u003ed\u003c/em\u003e\u003csub\u003e\u003cem\u003e002\u003c/em\u003e\u003c/sub\u003e\u0026thinsp;\u003cem\u003e=\u0026thinsp;nγ/2sinθ\u003c/em\u003e\u003csub\u003e\u003cem\u003e002\u003c/em\u003e\u003c/sub\u003e, \u003cem\u003eg=(0.3440-d\u003c/em\u003e\u003csub\u003e\u003cem\u003e002\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e)/(0.3440\u0026thinsp;\u0026minus;\u0026thinsp;0.3354)\u003c/em\u003e, where \u003cem\u003ed\u003c/em\u003e\u003csub\u003e\u003cem\u003e002\u003c/em\u003e\u003c/sub\u003e was the layer spacing between graphite crystals, \u003cem\u003eγ\u003c/em\u003e was the wavelength of X-ray, 0.15406 nm, \u003cem\u003eθ\u003c/em\u003e\u003csub\u003e\u003cem\u003e002\u003c/em\u003e\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;13.15 \u0026ordm;, g was the degree of graphitization, after calculation, the degree of carbonization of M70W30 carbon paper was 63%.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.4. TGA analysis\u003c/h2\u003e \u003cp\u003eTGA was analyzed to investigate the thermal stability of base paper and carbon paper, the result was shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. The base paper was containing 70% micro glass fiber and 30% unbleached Kraft pulp, the thermo gravimetric process of the base paper went through two stages: the loss of water and the degradation of cellulose, the temperature at maximum weight loss was 361\u0026deg;C. When the temperature rose to 800\u0026deg;C, the mass loss was about 29%. The residue without thermal decomposition was mainly micro glass fiber because the main component was silica, which had good heat resistance. Obviously, the mass loss of carbon paper was only 1.2% during heating from 20\u0026deg;C to 800\u0026deg;C, indicating that the carbon paper contained only a small amount of water vapor absorbed from the air, which also proved that the structure of carbon paper has undergone a great change, with a large reduction of oxygen groups.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e3.5. XPS analysis\u003c/h2\u003e \u003cp\u003eXPS can analyze the chemical composition with higher resolution. As can be seen from Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e\u003cb\u003e(A)\u003c/b\u003e, Si 2p and Si 2s were marked at 102 eV and 153 eV, C 1s was at 284 eV and O 1s was at 531 eV respectively in the full scan spectra of base paper and carbon paper of 0\u0026thinsp;~\u0026thinsp;600 eV. The content of C and O of base paper M70W30 was 51.85% and 38.32%. After carbonization, the content of C and O of carbon paper M70W30 was 57.68% and 32.92%. After carbonization, the O content in the base paper decreased, so the ratio of C/O increased from 1.35 to 1.75, implying that oxygen-containing groups were destroyed during pyrolyze treatment.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e \u003cb\u003e(B, C)\u003c/b\u003e showed high resolution base paper and carbon paper O 1s spectrum, the three obvious peaks at 531.1, 532.1 and 533.1 eV represented the carbonyl group C\u0026thinsp;=\u0026thinsp;O, the phenolic hydroxyl Ar-OH and C-O (C-OH, C-O-C, O\u0026thinsp;=\u0026thinsp;C-OR) groups (Ma et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Ishimaru et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2007\u003c/span\u003e), respectively. In Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e (D), the deconvoluted C 1s spectrum of base paper revealed four peaks at 284.6eV (C-C/C\u0026thinsp;=\u0026thinsp;C, 33.83%), 285.2 eV (C-O, 12.33%), 286.37 eV (C\u0026thinsp;=\u0026thinsp;O, 53.24%) and 289.2 eV (O\u0026thinsp;=\u0026thinsp;C-O, 0.60%). After carbonization, the chemical composition of C in carbon paper has changed. As seen in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e (E), the main peak was sp\u003csup\u003e2\u003c/sup\u003e hybrid graphitized C at 284.6eV (C-C/C\u0026thinsp;=\u0026thinsp;C) (Chen et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2014\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003e3.6. Wettability analysis\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e\u003cb\u003e(A)\u003c/b\u003e showed that water droplets (dyed with methyl blue) and kerosene was base paper were quickly absorbed by the base paper with a water contact angle of 0 \u0026ordm;, indicating that base paper was hydrophilic and oleophilic in the air because of hydroxyl groups (Yang et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). In general, the surface wettability of hydrophobic oil-water separation materials was constructed by chemicals modification, while carbon paper was prepared by one-step carbonization from base paper (Zheng et al., \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Figure\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e\u003cb\u003e(B)\u003c/b\u003e demonstrated water droplets were present in spherical shape on the carbon paper surface with a water contact angle of 140 \u0026ordm;C, which performed highly hydrophobic, kerosene was quickly absorbed by carbon paper, and the carbon paper has hydrophobic and oleophilic in the air.\u003c/p\u003e \u003cp\u003ePut base paper in kerosene, then add the water, parts of the water slid away, but the base paper was dyed blue, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e\u003cb\u003e(C)\u003c/b\u003e, suggesting that base paper was hydrophilic in the oil phase and can be polluted by water. When carbon paper was in kerosene, when water flowed through carbon paper, carbon paper was not contaminated by water, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e\u003cb\u003e(D)\u003c/b\u003e. Thus, the carbon paper was highly hydrophobic in oil. To verify the antifouling performance, carbon paper was dropped into the mixture of kerosene and water, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e\u003cb\u003e(E)\u003c/b\u003e, carbon paper descended slowly and lodged between the oil phase and water phase interface, using external force pressed carbon paper to the water phase, when loosed the tweezers, carbon paper floated back to interface soon, took out the carbon paper and found that there was no blue water on the surface, it showed that the carbon paper in the oil phase had the good self-cleaning capacity and pollution prevention performance.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e3.7. Oil-water separation performance of carbon paper\u003c/h2\u003e \u003cdiv id=\"Sec16\" class=\"Section3\"\u003e \u003ch2\u003e3.7.1. Separation of slick oil\u003c/h2\u003e \u003cp\u003eOil and water exist in various forms, mainly including floating oil, emulsified oil and dissolved oil (Huang et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). The separation of oil slick and emulsified oil is a focus of oil water separation research. The thickness of M70W30 carbon paper was about 0.32 mm, which was suitable to be used as a filter layer to separate oil slick and emulsified oil by separation device in the laboratory.\u003c/p\u003e \u003cp\u003eMixed 10 mL of dichloromethane and 10 mL of water, stirred and poured into the separation device. Carbon paper was sandwiched in the middle with an effective area of about 1.76 cm\u003csup\u003e2\u003c/sup\u003e, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e\u003cb\u003e(A)\u003c/b\u003e. When the mixture was transferred to the carbon paper, the blue water phase touched the carbon paper first, followed by the oil phase due to the density difference. Carbon paper was hydrophobic in air and oil. The water phase was repelled, while the oil phase can pass through smoothly. When the separation was completed, the oil phase completely entered the receiving bottle, and the water phase stayed above the carbon paper. Carbon paper also showed good separation efficiency on light density oil and water mixtures such as kerosene, n-hexane, and engine oil. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e\u003cb\u003e(B)\u003c/b\u003e, the separation efficiency of light oil and heavy oil was all above 99%. In order to explore the reuse performance of carbon paper, after the separation of dichloromethane and water mixture, the carbon paper was washed with methanol and dried in air, after 5 cycles of testing, the results as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e\u003cb\u003e(C)\u003c/b\u003e, the separation performance showed good stability with efficiency more above 99%, and the flux 2600\u0026thinsp;~\u0026thinsp;3400 L/m\u003csup\u003e2\u003c/sup\u003e\u0026middot;h. The M70W30 carbon paper was compared with the oil-water separation materials published in recent years, as shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. It was found that the membrane had high separation flux and high separation efficiency.\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\u003eMaterials previously reported for water/oil mixture separation are summarized.\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=\"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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSamples\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWCA\u003c/p\u003e \u003cp\u003e(\u0026deg;)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSeparation Pressure\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFlux\u003c/p\u003e \u003cp\u003e(L\u0026middot;m\u003csup\u003e2\u003c/sup\u003e\u0026middot;h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eEfficiency (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eRef.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSA-NiCo-CH@Al\u003csub\u003e2\u003c/sub\u003eSiO\u003csub\u003e5\u003c/sub\u003e FP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e153\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e400\u0026ndash;7000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e95.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eChen et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2021\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePDMS/UiO-66-NH\u003csub\u003e2\u003c/sub\u003e@CP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e162\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100\u0026ndash;500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eChen et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2024\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePF@PDA/BaSO4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e156\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e500\u0026ndash;600\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYang et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2020\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePoly(DR-DMP)@HAP fabric\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e162\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8000\u0026ndash;9000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eWang et al., \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2024\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDTS@paper\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e165\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e500\u0026ndash;600\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e94\u0026ndash;96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYang et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2023\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEP@PDMS@Fe\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@SiO\u003csub\u003e2\u003c/sub\u003e@PP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e155\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e40\u0026ndash;130\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eLi et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eM70W30 carbon paper\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e140\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2600\u0026ndash;3400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eThis work\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section3\"\u003e \u003ch2\u003e3.7.2. Separation of emulsified oil\u003c/h2\u003e \u003cp\u003eDue to the good stability of emulsified water (Zhang et al., \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2023\u003c/span\u003e) and its size usually less than 20 \u0026micro;m in diameter (Ge et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), water-in-oil emulsion was covered by oil film and has lower surface tension, which impeded the aggregation of water droplets (Wang et al., \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). In this experiment, stable emulsion was prepared under high speed dispersive agitation. M70W30 carbon paper was used to separate the emulsion, successfully separating emulsified water only under gravity, separation efficiency reached 98.5%, and flux reached 1200 L/m\u003csup\u003e2\u003c/sup\u003e\u0026middot;h, which was higher than the usual cellulose-based separation media, due to the higher porosity of carbon paper.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e\u003cb\u003e(A)\u003c/b\u003e showed that the appearance of emulsified oil was a milky solution, the particle diameter of the original emulsion with a wider droplet size distribution under the optical electron microscope, the average diameter was 959 nm measured by laser particle size analyzer. After separation, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e\u003cb\u003e(B)\u003c/b\u003e, kerosene became clear and transparent, no emulsified particles were observed by the optical electron microscope, and the average diameter was 1.1 nm measured by a laser particle size analyzer.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e\u003cb\u003e(C)\u003c/b\u003e depicts the separation mechanism of emulsion separation. The droplets of emulsion were captured by the micro glass fiber in the form of coalescence, the adjacent emulsion droplets squeezed and collided on the carbon paper and then flocculated into large droplets, the large droplets were released and separated from the carbon paper and achieved oil water separation (Li et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). When the emulsion was close to the filter material, the capture efficiency depended on the fiber diameter, the diameter of the emulsion droplet and the flow rate. In this experiment, the emulsion particles were captured by the labyrinth structure of carbon paper, after being squeezed and collided, the emulsion droplets accumulated into large particles. The mean pore size of carbon paper was measured as 4.51 \u0026micro;m, which could guarantee the efficient emulsion breaking, besides, the released water was gathered above while the oil passed through the carbon paper.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"4. Conclusions","content":"\u003cp\u003eIn this paper, unbleached sulfated coniferous wood pulp and microglass fibers were used as raw materials, and the wet papermaking technology was used to produce. The paper was obtained by high temperature carbonization with different sizes of carbon paper. When the content of microglass fiber was 70%, the carbon paper had better toughness, with an average pore size of 4.51\u0026micro;m and a porosity of 90.22%. After high-temperature carbonization, the carbon paper has high thermal stability, a water contact angle of 140\u0026ordm; in the air, and also exhibits high hydrophobicity and anti-pollution properties in the oil phase. Water-oil separation experiments on M70W30 carbon paper showed that the separation efficiency of this material for oil-water mixtures reached more than 99%, and that for water-in-oil emulsions reached 98.5%, which was higher than the separation performance of cellulose-based filter paper. Therefore, carbon paper is a potential effective filter material for separating floating oil and emulsified oil.\u003c/p\u003e"},{"header":"Declarations","content":" \u003cp\u003e \u003cstrong\u003eConflict of interest\u003c/strong\u003e \u003cp\u003eThe authors declare that there are no conflicts of interest related to the publication of this article in this journal.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eEthical approval\u003c/strong\u003e \u003cp\u003eThis article does not include any studies conducted by any of the authors on either humans or animals. We did not gather any specimens of both humans and animals.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eEthical standards\u003c/h2\u003e \u003cp\u003eThis study was carried out based on Compliance with Ethical Standards.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eClinical trial number\u003c/strong\u003e \u003cp\u003e Not applicable.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eConsent for publication\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThe National Key Research and Development Program of China (No.2022YFC2105503).\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eQian Yang: Methodology, Investigation, Formal analysis. Mingyue Zhao: Investigation, Formal analysis, Writing-original draft. Lanfeng Hui: Conceptualization, Funding acquisition, Writing-review \u0026amp; editing. Jieting Xin and Tingting Zhang: Test and Data. Zhong Liu: Resources, Writing-review \u0026amp; editing. Jiayan Li: Investigation, Formal analysis. All authors reviewed the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThis project was financially supported by the National Key Research and Development Program of China (No. 2022YFC2105503).\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data that support the findings of this study are available from the corresponding author, professor Hui , upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAbuhantash F, Abuhasheesh YH, Hegab HM et al (2023) Hydrophilic, oleophilic and switchable Janus mixed matrix membranes for oily wastewater treatment: A review. 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Process Saf Environ Prot 165:173-180. https://doi.org/10.1016/j.psep.2022.07.014\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":"cellulose","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cels","sideBox":"Learn more about [Cellulose](https://www.springer.com/journal/10570)","snPcode":"10570","submissionUrl":"https://submission.nature.com/new-submission/10570/3","title":"Cellulose","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-5086335/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5086335/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eSeparating emulsified oil/water mixture is full of challenges. Special permeable wetted surfaces can separate emulsions but usually require modification by fluorine or silicon based chemicals, which can cause second pollution after use. Carbon aerogels are new chemical free porous hydrophobic materials, which provide a promising approach to selectively adsorb oil from oil water mixture. However, during the course of the fabrication of carbon aerogels, freeze drying is essential, which is time-consuming and energy-intensive process. In this article, we introduced wet papermaking technology manufacturing base paper to replace freeze drying, followed by carbonization in N\u003csub\u003e2\u003c/sub\u003e at 800 \u0026ordm;C, hydrophobic carbon paper with a porosity of 90.22% was obtained when the content of micro glass fiber was 70%. The resulting carbon paper not only separates oil slick but also separates emulsified oil/water mixture with an efficiency of 98.5% and flux 1200 L/m\u003csup\u003e2\u003c/sup\u003e\u0026middot;h.\u003c/p\u003e","manuscriptTitle":"Chemical free and hydrophobic carbon paper for effective separation emulsified oil/water mixture based on cellulose and micro glass fiber","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-04 09:29:38","doi":"10.21203/rs.3.rs-5086335/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-10-12T16:56:44+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-10-12T16:54:52+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-09-30T01:14:43+00:00","index":"","fulltext":""},{"type":"submitted","content":"Cellulose","date":"2024-09-14T01:12:22+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"cellulose","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cels","sideBox":"Learn more about [Cellulose](https://www.springer.com/journal/10570)","snPcode":"10570","submissionUrl":"https://submission.nature.com/new-submission/10570/3","title":"Cellulose","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"7ab0a9dd-f7bb-4fdf-a674-ceafbfb91801","owner":[],"postedDate":"December 4th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-02-24T16:05:51+00:00","versionOfRecord":{"articleIdentity":"rs-5086335","link":"https://doi.org/10.1007/s10570-025-06402-4","journal":{"identity":"cellulose","isVorOnly":false,"title":"Cellulose"},"publishedOn":"2025-02-17 15:57:27","publishedOnDateReadable":"February 17th, 2025"},"versionCreatedAt":"2024-12-04 09:29:38","video":"","vorDoi":"10.1007/s10570-025-06402-4","vorDoiUrl":"https://doi.org/10.1007/s10570-025-06402-4","workflowStages":[]},"version":"v1","identity":"rs-5086335","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5086335","identity":"rs-5086335","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}