Removal of Pollutants from Landfill Leachate by Adsorption with Nano Zero Valent Iron Particles (nZVI): Adsorption Isotherms and Kinetic Studies

Removal of Pollutants from Landfill Leachate by Adsorption with Nano Zero Valent Iron Particles (nZVI): Adsorption Isotherms and Kinetic Studies | 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 Removal of Pollutants from Landfill Leachate by Adsorption with Nano Zero Valent Iron Particles (nZVI): Adsorption Isotherms and Kinetic Studies Serdar Göçer, Zeynep Zaimoğlu, Kevser CIRK This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-1692542/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Nano zero-valent iron (nZVI) is an effective adsorbent for removing various organic and inorganic contaminants. In this study, nZVI particles, synthesized in our previous work, were used for landfill leachate pre-treatment. The adsorption performance was tested at various adsorbent concentrations (50-500mg Fe 0 /L), pH (3–8), and contact times (15-330min). Chemical Oxygen Demand (COD), Dissolved Organic Carbon (DOC), Nitrate (NO 3 − ) and Ammonium (NH 4 + ) removal efficiency was approximately 75%, 60%, 57%, and 33%, respectively. The obtained data were fitted well by the Langmuir isotherm and adsorption kinetics of pseudo-second-order equations (R 2 > 0.9). The adsorption capacities were found to be 29.62mg/g, 21.01mg/g, and 3.12mg/g, for DOC, NH 4 + , and NO 3 − respectively at Fe 0 concentration of 50mg Fe 0 /L, pH of 8, and contact time of 120min which was determined as the effective operational conditions in this work. The obtained removal levels were higher compared to the conventional activated carbon adsorption (72.3%). Results suggest that nZVI has the potential to create effective adsorption relevant to landfill leachate pre-treatment thereby providing more efficient biological treatment by decreasing important pollutants before biological treatment. Zero Valent Iron Landfill Leachate Adsorption Equilibrium Isotherms Kinetics Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Introduction Adsorption is a significant treatment technology when used singly or in a combined treatment process to remove organic and inorganic substances (Kurniawan and Lo 2009; Oloibiri et al. 2017; Lee and Hur 2016; Kulikowska et al. 2014; Rodriguez et al. 2004). In recent years, nanoparticles (NPs) have been proposed as efficient adsorbents in the remediation of water and soil because of their unique atomic properties, higher reduction capacity, higher removal efficiency, magnetic property, non-toxic, molecular, and chemical properties compared to traditional adsorbents such as granulated -powdered and fibers activated carbons (GAC, PAC, ACF) (Yantasee et al. 2007; Chang et al. 2005; Liu et al. 2008; Hu et al. 2004; Yuan et al. 2010). All these properties can be used in the treatment of different types of wastewaters. The commonly used NPs for wastewater treatment are zero-valent metal nanoparticles, metal oxides nanoparticles, carbon nanotubes, and nanocomposites. Among them, the zero-valent iron nanoparticles (nZVI) have achieved very interesting and promising results for various pollutant remediation such as pesticides, polychlorinated hydrocarbons, chlorobenzenes, coloring agents, etc (Ghasemzadeh et al. 2014 , Galdames et al. 2020 ). Landfill leachate (LFL) is very strong wastewater and causes environmental concern due to the wide range of polluting parameters it contains. Landfill leachate is dark brown colored and odorous wastewater containing many suspended and dissolved organic substances, pathogenic substances, and toxic compounds such as heavy metals and heavy organic substances (Atmaca 2009 ; Gotvajn et al. 2009 ; Lou et al. 2009 ). LFL treatment is very complicated, expensive, and generally requires a combination of various treatment processes (Bashir et al. 2010 ). Although several methods of LFL treatment are available, adsorption has been widely used as pre-treatment or post-treatment due to its simplicity and cost-effectiveness. Furthermore, the adsorption process of LFL by nano zero-valent iron is preferred comparatively with other treatment methods due to its high efficiency, ease of operation, and ability to treat wastewater treatment. Although different isotherm models have been developed to describe the sorption of several pollutants on nZVI, there has been very limited information on adsorption performance towards landfill leachate. Kashitarash et al. ( 2012 ) reported fast removal efficiency of 47.94% for COD in 10 min at optimal conditions however sorption interactions onto nZVI particles have not been included in this study. Thus, for a deeper understanding of the LFL treatment and the related sorption interactions onto nZVI particles, the Langmuir and Freundlich isotherms have been considered in this study. Moreover, pseudo 1st order, pseudo 2nd order, kinetics models were applied to the sorption data for a deeper insight into the removal mechanism. Hence, the main objective of this study is to investigate the suitability of the selected isotherm and kinetic models in describing the treatment of LFL by nZVI. Besides, DOC, COD, NH 4 + , NO 3 - and color of LFL and the effect of pH, reaction time, and nZVI dosage variation were investigated to determine the optimum conditions. Material And Methods Preparation of nZVI The nZVI was synthesized with dispersing agent, polyethylene glycol (PEG-4000). The basic principle of the synthesis was that ferrous ion was rapidly reduced to nZVI by borohydride solution according to the following reaction (Eq. 1) (He et al. 2012 ): Fe 2 + (aq) + 2BH 4 − (aq) + 6H 2 O→Fe 0 (s) + 2B(OH) 3(aq) + 7H 2 ↑ (1) In this method; 1.7868 g FeSO 4 •7H 2 O was dissolved in 90 mL 4/1 (v/v) ethanol/deionized water mixture in a 500-mL bottle and then 0.3 g PEG-4000 was added into the above solution. The temperature was kept at 20°C. The solution was stirred at 220 rpm for 30 min to ensure that PEG-4000 was completely dissolved. Before reductant addition, the solution pH was adjusted to about 6.5 with 1 M NaOH. Then, 50 mL of 1.3883 g KBH 4 aqueous solution was added dropwise into the mixture at 220 rpm. The solution was stirred for another 30 min after the addition of all KBH 4 . Then the resulting black solid particles were washed with deoxygenated water three times and deoxygenated absolute ethanol twice and were collected by magnetic separation. Finally, the nZVI particles were dried at 70°C and stored in a under N 2 gas to prevent nZVI oxidation from atmospheric oxygen. In our previous work, synthesized nZVI characterization was carried out using XRD, SEM, and EDX techniques (Gocer et al. 2019). Landfill Leachate Raw LFL was collected from a municipal sanitary landfill located in Kahramanmaras, Turkey. The total amounts of LFL deposited daily were 815—830tons. LFL was collected from the equilibration tank and stored at 4°C until used. The characteristics of raw LFL is summarized in Table 1. Table 1 Landfill Leachate Characterization Parameters Concentration Parameters Concentration Total Organic Carbon (DOC) 7058±400(mg/L) NO 2 - 320±20(mg/L) COD 16000±1500(mg/L) NO 3 - 670±40(mg/L) BOD 1500±300(mg/L) Pt-Co (Color unit) 6380±300 NH 4 + -N 2120±200(mg/L) PO 4 -3 -P 78±10(mg/L) Adsorption experiments and capacity The effect of various parameters including pH (3–8), contact time (15-330min), nZVI concentration (50–500 mgFe 0 /L) was tested on NН 4 + , NO 3 − , DOC, and COD removal in batch adsorption experiments, for the evaluation of the optimum process conditions. (Table 2 ). Table 2 Experimental Plan Nano Zero Valent Iron (nZVI) Adsorbent Concentration (mgFe 0 /L) pH Mixing Rate (rpm) Contact Time (min) Temperature ( o C) 50 3 4 5 6 7 8 200 15–330 Room Temperature (25 o C) 100 3 4 5 6 7 8 200 3 4 5 6 7 8 300 3 4 5 6 7 8 400 3 4 5 6 7 8 500 3 4 5 6 7 8 The adsorption capacity, qe, (mg g − 1 ), and pollutants removal efficiency (%) of the tested nZVI were calculated by Eqs. ( 2 ) and ( 3 ), respectively: In Eqs. ( 2 ) and ( 3 ), V is the volume of the leachate (L), W is the amount of adsorbent (g), Co and Ce are the initial and equilibrium concentrations of pollutants (mg L − 1 ) in the leachate, respectively. Analyses All samples were centrifuged at 4000 rpm for 5 min (Eppendorf Centrifuge 5415R, Hamburg, Germany) and then, were filtered using a sterile syringe 0.45μm filter (Sartorius AG, Gottingen, Germany). DOC and TN concentrations were analyzed using a TOC instrument coupled with TN (Shimadzu TOC-VCPN, Kyoto, Japan). The pH was measured by a pH meter (Thermo, Orion 4 Star, Indonesia). Ionic composition of influent and effluent samples (ammonium, nitrate) was measured by ion chromatography (Dionex ICS-3000, Sunnyvale, CA, USA). The COD measurements were carried out according to the dichromate-closed reflux Colorimetric Method described in Standard Methods (Standard Methods, 5220 D). The color was analyzed as Pt-Co units. Pt-Co color measurements were performed spectrophotometrically at 465 nm during lab-scale studies. Adsorption Isotherms and Kinetics The Langmuir, Freundlich isotherms and pseudo 1st order, pseudo 2nd order kinetics models were selected to simulate the isotherm adsorption of nZVI in this work. Adsorption kinetics The amount of nZVI absorbed on the pollutants was calculated using the following equation (Eq. 4 ): $${q}_{e}=\left(Co-Ct\right)*\frac{V}{m}$$ 4 Where qe expresses the adsorption capacity (mg g − 1 ); C 0 and Ct are pollutant concentrations (such as DOC, COD, NH 4 + , and NO 3 − ) (mg L − 1 ) at time 0 and t, respectively. V indicates the volume of solution (mL) and m is the mass of nZVI (g). Adsorption kinetic parameters are divided into two; these are expressed as pseudo-first-order equations (Ho, 2004 ) and pseudo-second-order equations (Azizian 2004 ; Ho 2006). Pseudo-first-order kinetics The so-called first-order equation (Lagergren's equation) is expressed as the adsorption of solid-liquid solutions based on the adsorption capacity of solids (Ho, 2004 ). The linear form of the so-called first-order model can be expressed by the following equation (Eq. 5 ): $$Log\left(qe-qt\right)=Logqe-\left(\frac{k1}{2.303}\right)t$$ 5 where qe and qt (mg g − 1 ) are defined as the adsorption capacities at time t(h) at equilibrium, respectively. Pseudo-second order kinetics The pseudo-second-order kinetics are used to define chemical adsorption from liquid solutions (Azizian 2004 ; Ho 2006). The linear expression of this kinetics is shown in Eq. 6 below (Eqs. 6 ): where k 2 is the rate constant for pseudo-second-order adsorption (g mg − 1 h − 1 ) and k 2 qe 2 is the initial adsorption rate (mg g − 1 h − 1 ). Adsorption isotherm models Freundlich isotherm Freundlich isotherm models are valid for both monolayer (chemisorption) and multilayer adsorption processes. This isotherm is known adsorbing to the heterogeneous surface of an adsorbent. The linear form of the Freundlich equation is expressed as (Eq. 7 ): $$Lnqe=LnKF+\frac{1}{n}LnCe$$ 7 where K F and n are Freundlich isotherm constants related to adsorption capacity and adsorption intensity, respectively and Ce is the equilibrium concentration (mg L − 1 ) (Tan 2009 ). Langmuir isotherm The Langmuir isotherm assumes monolayer adsorption on a single surface with a certain number of adsorption sites. After the adsorption zone is filled, no more tendency takes place. In this way, it will reach a saturation point where maximum adsorption of the surface will be achieved. The linear form of the Langmuir isotherm model is expressed as (Eq. 8 ): $$\frac{Ce}{qe}=\frac{Ce}{qmax}+\frac{1}{KLqmax}$$ 8 where K L is the Langmuir constant related to the energy of adsorption and qm is the maximum adsorption capacity (mg g − 1 ) (Barkat et al. 2009 ; Chingombe et al. 2006 ). Results And Discussion Adsorption Experiments and Capacities In the adsorption experiments, optimum conditions were examined for different pH (3-4-5-6-7-8) and contact time (15-330min). In terms of COD, optimum conditions were determined at pH and contact time of 8 and 120 min, respectively. The highest COD removal efficiency was about 60%. After that, the effect of increasing zero-valued iron concentration (50–500 mg/L, Table 2 ) on pollutant removal was tested at pH of 8 and contact time of 120min. Optimum zero-valent iron concentration was 50mg/L in terms of COD, DOC, NH 4 + , and NO 3 − , corresponding to removals of 75%, 60%, 57% and 33%, respectively. Figure 1 . shows the effect of increasing nZVI concentration on the adsorption capacity (qe). It was noticed the increase in nZVI from 50 to 500mg/L decreased the adsorption capacity of pollutants which may be attributed to the collection of the nanoparticles. According to Fig. 1 nZVI adsorption capacity for DOC, NH 4 + and NO 3 − were found to be 29.62 mg/g, 21.01 mg/g, and 3.12 mg/g at 50mg/L nZVI concentration, respectively. Adly et al. ( 2022 ) reported that they investigated the removal of phosphorus adsorption on nanoscale zero-valent iron (nZVI)/activated carbon composite. They found that the maximum adsorption capacity at pH 4 was 53.76 mg/g. They obtained high adsorption capacity due to the use of nZVI and activated carbon (AC) as a support material. In another study, biochar prepared with nZVI and sewage sludge was used for arsenic removal from aqueous solutions. They found relatively higher adsorption capacity (60.61 mg/g) compared to our results which was probably due to the adverse effect of the strong and the complicated LFL (Liu et al. 2021 ). Halim et al. ( 2010 ) reported that composite medium, zeolite, and activated carbon the adsorption capacities of 32.89 mg/g, 17.45 mg/g, and 6.08 mg/g respectively which is in good agreement with our study. Eljamal et al., ( 2022 ) reported that nanoparticles have great potential for the practical applications of pollutants removal from wastewater. Unlike our study, according to the studies of Boparai et al. ( 2011 ) nZVI particles reported removal of Cd 2 + in the concentration range of 25–450 mg/L. The maximum adsorption capacity of nZVI for Cd 2+ was determined as 769.2 mg/g. They reported that nZVI can be used as an efficient adsorbent for the removal of cadmium from polluted water sources. Adsorption Isotherms Adsorption isotherms are a widely used method to determine the isotherm equilibrium condition of an adsorption system. Also this method; helps to decide the surface area of the adsorbent, the volume, size distribution of the pores, the temperature of adsorption, and the absorbability of a gas or vapor on the adsorbent. Adsorption of DOC, NO 3 − , NH 4 + by nZVI particles was modeled using the Freundlich and Langmuir isotherms with the quality of the fit assessed using the correlation coefficient (Fig. 2 – 4 ). Isotherm parameters in terms of dissolved organic carbon (DOC) are given in Table 3 below. Table 3 Adsorption Isotherms Parameters (DOC parameter) Langmuir Isotherms Freundlich Isotherms Adsorbent Concentration (mg/L) Slope K L q max R L R 2 K L . Ce qe Slope K F n R 2 50 0,0756 3,25 13,22 0,00056 0,9931 1765,95 13,22 -0,9014 1,574 -1,109 0,9927 100 0,7835 3,64 1,276 0,00013 0,971 7211,41 1,276 -3,2661 1,261 -0,306 0,9866 200 1,6968 0,276 0,588 0,00011 0,9573 7211,41 0,588 -3,3491 1,173 -0,298 0,9799 300 0,4893 5,12 2,04 0,0022 0,9669 448,224 2,04 -2,9702 2,341 -0,342 0,9858 400 2,2328 4,339 0,447 0,00017 0,9839 5787,6 0,447 2,6268 1,07 -0,38 0,9922 500 3,2552 1,83 0,307 0,00015 0,923 6555,25 0,307 -2,735 1,015 -0,365 0,9632 The slope and intercept of plots of Ce/qe versus Ce, at adsorbent concentration, were used to calculate qm and K L (Fig. 2 A). The size of qmax and K L indicates high adsorption capacity (50mg/L adsorption concentration, Table 3 ). If K L Ce < > 1 is high. When the table above is evaluated, it is observed that K L Ce is > > 1 and the amount of adsorption is high. If the R L value is greater than 1, the adsorption process is inconvenient, it is linear if it is equal to 1, it is convenient if it is between 0 and 1, and it is irreversible if it is 0 (Eq. 7 ). When the Langmuir isotherm is examined, it is observed that the R L value is between 0 and 1 (Table 3 ). The Freundlich isotherm constants K F and n are determined from the intercept and slope of a plot of Lnqe versus LnCe (Fig. 2 B). It is 1/n from the slope of the LnCe graph against Lnqe and LnK F from the cutting point of the y axis (Eq. 6 ). The high LnK F and n values show that sorbent has a high tendency to adsorption and adsorption capacity. The value of 1/n ranging from 0 to 1 is expressed as a measure of an adsorption tendency and heterogeneity that becomes heterogeneous as it approaches zero. 1/n 1 indicates compatibility with adsorption condition. As a result, it is observed that the DOC removal adapts to the Langmuir isotherm. The best adsorption capacity suitable for the Langmuir isotherm occurred at a concentration of 50 mg /L nZVI (R 2 > 0.9931). Langmuir isotherm parameter fits (Table 3 ) for DOC removal efficiency adsorption on nZVI yielded isotherms that were in good agreement with observed behavior (R 2 ≥ 0.99). Maamoun et al. ( 2021 ) investigated the suitability of various adsorption isotherms and kinetic models to explain the removal of phosphorus (P) from aqueous solutions by nanoscale zero-valent-iron (nZVI). They found that the Langmuir isotherm and the pseudo-second-order kinetic model are the best models with the highest linear and nonlinear correlation (R 2 ). Similarly; in another study, the adsorption capacity of synthesized modified adsorbent (nZVI/AC) for arsenite and arsenate at pH 6.5 was calculated from Langmuir adsorption isotherms in batch experiments was 18.2 and 12.0 mg/g, respectively. It can be concluded that nZVI without the use of support material reached the similar results due to the its positive effect (Zhu et al. 2009 ). Adsorption of NO 3 − by nZVI particles was modeled using the Freundlich and Langmuir isotherms with the quality of the fit assessed using the correlation coefficient (Fig. 3 A-B). Isotherm parameters in terms of NO 3 − removal efficiency is given in Table 4 below. Table 4 Adsorption Isotherms Parameters (NO 3 − parameter) Langmuir Isotherms Freundlich Isotherms Adsorbent Concentration (mg/L) Slope K L q max R L R 2 K L . Ce qe Slope K F n R 2 50 0,5935 1,82 1,67 0,0045 0,9999 220,2 1,67 -0,8096 1,26 -1,23 0,9999 100 0,5769 1,78 1,73 0,0046 0,9999 211,82 1,73 -0,781 1,264 -1,28 0,9999 200 0,6166 1,84 1,62 0,0043 0,9999 231 1,62 -0,8412 1,253 -1,18 0,9999 300 0,6166 1,84 1,62 0,0043 0,9999 234 1,62 -0,8412 1,253 -1,18 0,9999 400 0,6367 1,92 1,57 0,0042 0,9994 234,24 1,57 -0,8688 1,256 -1,151 0,9993 500 1,0433 2,43 0,958 0,0024 0,9995 400,95 0,958 -1,3999 1,181 -0,71 0,9996 It was observed that NO 3 − removal is fitted to the Freundlich isotherm (Fig. 3 B). Additionally, K L Ce is > > 1 and the amount of adsorption is high. According to Langmuir isotherm, it was observed that the R L value is between 0 and 1 (Table 4 ) confirming Langmuir isotherm is suitable NO 3 − removal. The high LnK F and n values show that sorbent has a high tendency for high adsorption capacity. Unlike our study, Kanel et al. ( 2005 ) investigated arsenic removal efficiency in groundwater by using nZVI as an adsorbent and observed 3.5 mg As(III)/g adsorption capacity with Freundlich isotherm. Other studies using new composite materials for landfill leachate treatment found different results. Langmuir and Freundlich reported that the isotherm's regression coefficients (R 2 ) for COD and ammonia nitrogen were 0.9971 and 0.9914, respectively (Detho et al. 2021 ). Hassemi et al. (2021) investigated ammonium removal efficiency from landfill leachate (LL) using montmorillonite/hematite nanocomposite (M/HNC). They reported that the ammonium adsorption data on the nanoparticle material agreed with the Langmuir isotherm models. Isotherm parameters in terms of NH 4 + removal efficiency are given in Table 5 below. Table 5 Adsorption Isotherms Parameters (NH 4 + parameter) Langmuir Isotherms Freundlich Isotherms Adsorbent Concentration (mg/L) Slope K L q max R L R 2 K L . Ce qe Slope K F n R 2 50 0,2399 3,56 4,16 0,00013 0,9725 7298 4,16 -2,7844 1,421 -0,359 0,9872 100 0,7312 4,8 1,36 0,00008 0,9899 11942,4 1,36 -3,7169 1,276 -0,269 0,9959 200 1,5718 4,95 0,636 0,00008 0,9944 12300,7 0,636 -3,9212 1,158 -0,255 0,9978 300 2,6273 5,31 0,38 0,00007 0,9949 13142,2 0,38 -4,1943 1,094 -0,238 0,9981 400 2,2266 3,8 0,449 0,0001 0,9737 9541,8 0,449 -3,0823 1,074 -0,324 0,9881 500 2,9092 3,83 0,343 0,0001 0,9747 9720,5 0,343 -3,1881 1,037 -0,313 0,9905 In terms of NH 4 + removal efficiency and zero-valued iron concentration, it was observed that it fits to the Freundlich isotherm (Fig. 4 B). The size of qmax and K L in Langmuir isotherm indicates high adsorption capacity (Table 5 ). When all these results were examined; Langmuir and Freundlich isotherm equations are created upon ammonium removal and with increasing adsorbent concentrations. These results showed that the optimum conditions for adsorption capacity and isotherms were at 50 mg/L nZVI (R 2 > 0.9). Mittal ( 2006 ) used chicken feathers as an adsorbent for the removal of toxic substances containing dye waters. They found adsorption data, Langmuir and Freundlich confirmed with adsorption isotherm models. According to our study, similar results were obtained in terms of both removal efficiency and adsorption isotherms. In another study, the adsorption capacities of As(III) and As(V) were obtained as 35.83 mg g − 1 and 29.04 mg g − 1 , respectively, as determined from Langmuir adsorption isotherms in batch experiments (Wang et al. 2014 ). When compared with our study, it is seen that the adsorption capacity is high. Similarly; in another study, lead and cadmium adsorption efficiency from leachate by the natural zeolite clinoptilolite was investigated and they found best isotherm model for lead adsorption fits the Freundlich model, while for cadmium it fits the Langmuir model (Farai et al. 2021). Adsorption Kinetics The adsorption rate is a vital parameter to assess the efficiency of an adsorbent for the removal of contaminates. The adsorption of nitrate (NO 3 − ), ammonium (NH 4 + ), and dissolved organic carbon (DOC) onto the nZVI was explained through pseudo-first-order and pseudo-second-order kinetic models. Pseudo-first-order kinetic model examines the change in adsorption capacity depending on time. Kinetics parameters in terms of dissolved organic carbon (DOC), nitrate (NO 3 − ), and ammonium (NH 4 + ) removal efficiency are given in Fig. 5 - 7 A-B. k 1 and qe, at the adsorbent concentration evaluated experimentally, were calculated using the slope and intercept of plots of log(qe − qt) versus t (Fig. 5 A, Table 6 ), (Eq. 4 – 5 ). Pseudo-second-order adsorption parameters qe and k 2 in Eq. ( 5 ) were determined by plotting t/qt versus t (Table 6 ). Table 6 Adsorption Kinetics Parameters (DOC parameter) Pseudo-first-order kinetics Pseudo-second-order kinetics Adsorbent Concentration (mg/L) Slope (k 1 ) qe (mg/mg) R 2 Slope (qe) k 2 R 2 50 -0,0001 0,0364 0,0114 0,0009 0,0009 0,9233 100 -0,0003 0,0324 0,0073 0,0006 0,0005 0,9673 200 -0,0008 0,033 0,00594 0,0006 0,0005 0,9673 300 0,0017 0,0336 0,2662 0,0006 0,0006 0,973 400 0,0013 0,0336 0,2487 0,0006 0,0006 0,9853 500 0,0027 0,0333 0,3835 0,0007 0,0006 0,9656 R 2 value in the adsorption kinetics equation; considering the adsorbent concentration and DOC removal efficiency, it is observed that the R 2 value is very close to 1 in the pseudo-second-order adsorption kinetic equation (R 2 = 0.9853, 400mg/L Fe 0 ), (Table 6 ). However, DOC was complied with pseudo-second-order adsorption kinetics (Fig. 5 B-Table 6 ). These results show that pseudo-second-order kinetics are adsorbed onto the nZVI surface via chemical interaction. Foul et al. ( 2009 ) investigated the removal efficiency of landfill leachate using two different adsorbents (activated carbon and limestone). Adsorption kinetics, on the other hand, determined their suitability to the pseudo-second-order kinetic model. Similarly, Boparai et al. ( 2011 ) used nZVI particles to investigate the removal of Cd 2+ (25–450 mg L − 1 ). They observed that the adsorption kinetics was well adapted using a pseudo-second-order kinetic model. In another study, they aimed to achieve both anionic and cationic dye removal efficiency by using a zero-valent-iron loaded composite nanoparticle material. The adsorption process of both dyes was well fitted with the Langmuir isotherm model and pseudo-second-order kinetic model (Eltaweil et al. 2021 ). Table 7 Adsorption Kinetics Parameters (NO 3 − parameter) Pseudo-first-order kinetics Pseudo-second-order kinetics Adsorbent Concentration (mg/L) Slope (k 1 ) qe (mg/mg) R 2 Slope (qe) k 2 R 2 50 - 0,0259 0,2654 0,0082 0,0082 0,9995 100 - 0,026 0,0002 0,0083 0,0083 0,9991 200 - 0,0258 0,0449 0,008 0,008 0,9994 300 - 0,0258 0,0449 0,008 0,008 0,9994 400 - 0,0259 0,0511 0,0079 0,008 0,991 500 -0,0002 0,0246 0,3195 0,0061 0,0062 0,9974 The rate parameters of these adsorption kinetic models listed in Table 7 – 8 indicate that adsorption of ammonia and nitrate from aqueous solution on nZVI obeys the pseudo-second-order kinetic model according to R 2 (> 0.99) (Fig. 6 – 7 ). Previous studies have reported that the adsorption of ammonia on zeolite obeys the pseudo-second-order model (Doğan et al. 2006; Lei et al. 2008 ). Genethliou et al. ( 2021 ) used natural zeolite for the removal of pollutants in raw landfill leachate. They reported that mostly followed the linear pseudo-second-order model with the isotherm and kinetic conformity they obtained, NH 4 + -N adsorption. In another study, used activated biochar-loaded nano-zero iron (A-BC-NZVI) to remove uranium from wastewater. They found that it complies with the pseudo-second-order equation and the maximum U(VI) adsorption amount of the Langmuir model at pH 6.0 was 331.13 mg/g (Zhang et al. 2021 ). Table 8 Adsorption Kinetics Parameters (NH 4 + parameter) Pseudo-first-order kinetics Pseudo-second-order kinetics Adsorbent Concentration (mg/L) Slope (k 1 ) qe (mg/mg) R 2 Slope (qe) k 2 R 2 50 0,0018 0,0018 0,07231 0,0005 0,0005 0,989 100 0,0005 0,0333 0,0647 0,0004 0,0004 0,9946 200 - 0,0329 0,0051 0,0004 0,0004 0,9983 300 0,0001 0,0328 0,0218 0,0004 0,0004 0,9989 400 -0,0003 0,0334 0,021 0,0004 0,0004 0,9895 500 -0,0002 0,0332 0,0143 0,0004 0,0004 0,9875 Conclusion Nano zero-valent iron (nZVI) can be used as an effective adsorbent for removing COD, DOC, NO 3 − and NH 4 + from landfill leachate. Equilibrium isotherms in this study were analyzed using Langmuir and Freundlich. Kinetic data were obtained and analyzed using pseudo 1st and pseudo 2nd equations. Optimum conditions were determined as pH 8, reaction time 120 minutes, and adsorbent dose 50mg/L nZVI. COD, DOC, NO 3 − and NH 4 + removal efficiency was approximately 75%, 60%, 57% and 33%, respectively. DOC, NH 4 + and NO 3 − adsorption capacities, respectively; It was found to be 29.62 mg/g, 21.01 mg/g and 3.12 mg/g. The experimental results were applied to isotherms commonly used in landfill leachate and the most suitable isotherm was found to be Langmuir. As a result of administering the experimental data to kinetic equation, the mechanism controlling the rate was determined and the most suitable model was found to be the pseudo 2nd equation. Results from this study suggest that nZVI is a very effective adsorbent for pollutants, as anticipated. Sorption kinetics is investigated to develop an understanding of controlling reaction pathways and the mechanisms of sorption reactions. In near future, nanoparticles may turn out to be the essential and indispensable components of water purification and treatment systems and facilities. Further research can be focused on improving the functional properties of nanoparticles to meet the versatile needs in both the detection and treatment of pollutants. Declarations Competing interest The authors declare no conflicts of interest. Acknowledgements This article was supported by the Scientific Research Unit of the Çukurova University. Project No: FDK-2019-11782. References Adly A, Mostafa NG, Elawwad A et al (2022) Adsorption of phosphorus onto nanoscale zero-valent iron/activated carbon: removal mechanisms, thermodynamics, and interferences Journal of Water Reuse and Desalination. Atmaca E (2009) Treatment of landfill leachate by using electro-Fenton method J Hazard Mater 163(1):109–114. Azizian S (2004) Kinetic models of sorption: a theoretical analysis J. Colloid Interface Sci 276, 47–52. Barkat M, Nibou D, Chearouche S, Mellah A et al (2009) Kinetics and thermodynamics studies of chromium(VI) ions adsorption onto activated carbon from aqueous solutions Chem. Eng. Process. 48, 38–47. Bashir MJ, Aziz HA, Yusoff MS, Adlan MN, et al (2010) Application of response surface methodology (RSM) for optimization of ammoniacal nitrogen removal from semi-aerobic landfill leachate using ion exchange resin Desalination 254(1–3), 154–161. Boparai HK, Joseph M, O’Carroll DM, et al (2011) Kinetics and thermodynamics of cadmium ion removal by adsorption onto nano zerovalent iron particles Journal of hazardous materials, 186(1), 458–465. Chingombe P, Saha B, Wakeman R.J, et al (2006) Sorption of atrazine on conventional and surface modified activated carbons J. Colloid Interface Sci 302, 408–416. Detho A, Daud Z, Rosli MA, Ridzuan MB, Awang H, Kamaruddin MA, Halim AA et al (2021) COD and ammoniacal nitrogen reduction from stabilized landfill leachate using carbon mineral composite adsorbent Desalination and Water Treatment, 210, 143–151. Doğan K, Yunus K, Mustafa T, Bulent A et al (2005) Removal of ammonium ion from aqueous solution using natural Turkish clinoptilolite J. Hazard. Mater B136, 604–609. Eljamal O, Eljamal R, Maamoun I, Khalil AM, Shubair T, Falyouna O, Sugihara Y et al (2022) Efficient treatment of ammonia-nitrogen contaminated waters by nano zero-valent iron/zeolite composite Chemosphere, 287, 131990. Eltaweil AS, El-Tawil AM, Abd El-Monaem EM, El-Subruiti GM et al (2021) Zero valent iron nanoparticle- loaded nanobentonite intercalated carboxymethyl chitosan for efficient removal of both anionic and cationic dyes ACS omega, 6(9), 6348–6360. Faraji M, Mehrizi EA, Sadani M, Karimaei M, Ghahramani E, Ghadiri K, Taghizadeh MS et al (2012) Isotherms and kinetics of lead and cadmium uptake from the waste leachate by natural and modified clinoptilolite International Journal of Environmental Health Engineering, 1(1), 26. Foul AA, Aziz HA, Isa MH, Hung YT et al (2009) Primary treatment of anaerobic landfill leachate using activated carbon and limestone: batch and column studies International Journal of Environment and Waste Management, 4(3–4), 282–298. Galdames A, Ruiz-Rubio L, Orueta M, Sánchez-Arzalluz M, Vilas-Vilela JL et al (2020) Zero-Valent Iron Nanoparticles for Soil and Groundwater Remediation International Journal of Environmental Research and Public Health, 17(16), 5817. Genethliou C, Triantaphyllidou IE, Giannakis D, Papayianni M, Sygellou L, Tekerlekopoulou AG, Vayenas DV et al (2021) Simultaneous removal of ammonium nitrogen, dissolved chemical oxygen demand and color from sanitary landfill leachate using natural zeolite Journal of Hazardous Materials, 406, 124679. Ghasemzadeh G, Momenpour M, Omidi F, Hosseini MR, Ahani M, Barzegari A et al (2014) Applications of nanomaterials in water treatment and environmental remediation. Frontiers of environmental science & engineering, 8(4), 471–482. Göçer S, Kozak M, Akgül V, Duyar A, Zaimoğlu Z, Cırık K et al (2019) Synthesıs Of Nanoscale Zero-Valent Iron (nZVI), International Symposium on Advanced Engineering Technologies (ISADET), (02–04 May 2019) p:828–833, Kahramanmaraş/Turkey. Gotvajn AZ, Tisler T, Zagorc-Koncan J et al (2009) Comparison of different treatment strategies for industrial landfill leachate J Hazard Mater, 162(2–3):1446–1456. Halim AA, Aziz HA, Johari MAM, Ariffin KS et al (2010) Comparison study of ammonia and COD adsorption on zeolite, activated carbon and composite materials in landfill leachate treatment Desalination, 262(1–3), 31–35. Hashemi H, Bahrami S, Emadi Z, Shariatipor H, Nozari M et al (2021) Optimization of ammonium adsorption from landfill leachate using montmorillonite/hematite nanocomposite: response surface method based on central composite design Desalination And Water Treatment, 232, 39–54. He P, Wang X, Liu Y, Liu X, Yi L et al (2012) Comparison of electrocatalytic activity of carbon-supported Au– M (M = Fe, Co, Ni, Cu and Zn) bimetallic nanoparticles for direct borohydride fuel cells. International journal of hydrogen energy, 37(16), 11984–11993. Ho YS (2004) Citation review of Lagergren kinetic rate equation on adsorption reactions, Scientometrics 59 (2004) 171–177. Kanel SR, Manning B, Charlet L, Choi H et al (2005) Removal of arsenic (III) from groundwater by nanoscale zero-valent iron Environmental science & technology, 39(5), 1291–1298. Kashitarash ZE, Taghi SM, Kazem N, Abbass A, Alireza R et al (2012) Application of iron nanaoparticles in landfill leachate treatment-case study: Hamadan landfill leachate Iranian journal of environmental health science & engineering, 9(1), 1–5. Lei L, Li X, Zhang X (2008) Ammonium removal from aqueous solutions using microwave-treated natural Chinese zeolite. Separation and purification Technology, 58(3), 359–366. Liu L, Zhao J, Liu X, Bai S, Lin H, Wang D et al (2021) Reduction and removal of As (V) in aqueous solution by biochar derived from nano zero-valent-iron (nZVI) and sewage sludge. Chemosphere, 277, 130273. Lou Z, Dong B, Chai X, Song Y, Zhao Y, Zhu N et al (2009) Characterization of refuse landfill leachates of three different stages in landfill stabilization process. J Environ Sci, 21(9):1309–1314. Maamoun I, Eljamal R, Falyouna O, Bensaida K, Sugihara Y, Eljamal O et al (2021) Insights into kinetics, isotherms and thermodynamics of phosphorus sorption onto nanoscale zero-valent iron. Journal of Molecular Liquids, 328, 115402. Mittal A (2006) Adsorption kinetics of removal of a toxic dye, Malachite Green, from wastewater by using hen feathers. Journal of hazardous materials, 133(1–3), 196–202. Rahmani AR, Ghaffari HR, Samadi MT et al (2011) A comparative study on arsenic (III) removal from aqueous solution using nano and micro sized zero-valent iron. Tan GQ, Xiao D (2009) Adsorption of cadmium ion from aqueous solution by ground wheat stems, J. Hazard. Mater. 164, 1359–1363. Wang C, Luo H, Zhang Z, Wu Y, Zhang J, Chen S et al (2014) Removal of As (III) and As (V) from aqueous solutions using nanoscale zero-valent iron-reduced graphite oxide modified composites. Journal of Hazardous materials, 268, 124–131. Yang CH (1998) Statistical mechanical study on the Freundlich isotherm equation, J. Colloid Interface Sci. 208, 379–387. Zhang Q, Wang Y, Wang Z, Zhang Z, Wang X, Yang Z et al (2021) Active biochar support nano zero-valent iron for efficient removal of U (VI) from sewage water. Journal of Alloys and Compounds, 852, 156993. Zhu H, Jia Y, Wu X, Wang H et al (2009) Removal of arsenic from water by supported nano zero-valent iron on activated carbon, J. Hazard. Mater. 172, 1591–1596. Additional Declarations No competing interests reported. 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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-1692542","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":108712344,"identity":"5f877ea3-6463-4da3-9f45-9c9e843d1d3c","order_by":0,"name":"Serdar Göçer","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABA0lEQVRIiWNgGAWjYJACCSjN/PBDxQEw68ADIrWwGUucOcDAA9KSQKQWBgneNogWBnxa5Nt7H974uadWjr+994GB5Lw7cvZihx8CbbGT023ArsXgzHFjy55nx4FuOm7woHDbM2Me6TQDoJZkY7MDOLRIpLFJ8Bw4lrhBIo3BQHLb4cQe6QSQlgOJ23BokZ//jE3yD0iL/DOgX+aAtKR/wKuF4QYbmzTPgRqgLWxALQ0gLTn4bTE4k8ZsLXPgANAvacBAPnbYmOd2TsGBBAPcfpFvP8Z4882BOmCIHQNGZc1hOfbZ6Zs/fKiwk8OlBQoOY9iOVzkI1BFUMQpGwSgYBSMYAADle2KZuvdn/gAAAABJRU5ErkJggg==","orcid":"","institution":"Çukurova University","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Serdar","middleName":"","lastName":"Göçer","suffix":""},{"id":108712345,"identity":"a0965b39-4a9a-45d2-a253-f23203198056","order_by":1,"name":"Zeynep Zaimoğlu","email":"","orcid":"","institution":"Çukurova University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zeynep","middleName":"","lastName":"Zaimoğlu","suffix":""},{"id":108712346,"identity":"a1effc03-9d59-4137-8a76-4c8ffb152658","order_by":2,"name":"Kevser CIRK","email":"","orcid":"","institution":"Kahramanmaras Sutcu Imam University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Kevser","middleName":"","lastName":"CIRK","suffix":""}],"badges":[],"createdAt":"2022-05-25 12:29:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-1692542/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-1692542/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":21885453,"identity":"7fd0fe00-af03-42d7-9427-00df70d8a6e9","added_by":"auto","created_at":"2022-05-25 17:20:13","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":6076,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of nZVI concentration on the adsorption capacity (qe) for DOC, NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e, and NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e by nZVI particles\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-1692542/v1/4765f493588bff63422cb1f3.png"},{"id":21885949,"identity":"081cf8c3-1b00-42fb-82a3-43379b442840","added_by":"auto","created_at":"2022-05-25 17:25:13","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":6731,"visible":true,"origin":"","legend":"\u003cp\u003e(A)\u003cstrong\u003e \u003c/strong\u003eLangmuir isotherms with DOC removal, (B) Freundlich isotherms with DOC removal\u003c/p\u003e","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-1692542/v1/1879b7f0f9073e075e43a2c3.png"},{"id":21885454,"identity":"c848ccd3-5f1d-4352-95b1-d289d1cc4752","added_by":"auto","created_at":"2022-05-25 17:20:13","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":5388,"visible":true,"origin":"","legend":"\u003cp\u003e(A) Langmuir isotherms with NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e removal, (B) Freundlich isotherms with NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e removal\u003c/p\u003e","description":"","filename":"Onlinefloatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-1692542/v1/564378100860e55a7f28b1b0.png"},{"id":21885458,"identity":"682ca8f7-cbe3-4aa3-876f-b6a928b61129","added_by":"auto","created_at":"2022-05-25 17:20:13","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":6571,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003e(\u003c/strong\u003eA) Langmuir isotherms with NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e removal, (B) Freundlich isotherms with NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e removal\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"Onlinefloatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-1692542/v1/3118732975ae9e66c6785c34.png"},{"id":21885951,"identity":"b02f9998-366e-47c3-b7df-aa0507d7e5c7","added_by":"auto","created_at":"2022-05-25 17:25:13","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":7658,"visible":true,"origin":"","legend":"\u003cp\u003e(A)\u0026nbsp;Pseudo first-order kinetics with DOC removal, (B) Pseudo second-order kinetics with DOC removal\u003c/p\u003e","description":"","filename":"Onlinefloatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-1692542/v1/bb28aa66f9f7097fc02a4d3f.png"},{"id":21885950,"identity":"1c440dc4-4c42-46c0-b458-8f93adec2ac7","added_by":"auto","created_at":"2022-05-25 17:25:13","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":6677,"visible":true,"origin":"","legend":"\u003cp\u003e(A) Pseudo first-order kinetics with NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e removal, (B) Pseudo second-order kinetics with NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e\u0026nbsp;removal\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"Onlinefloatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-1692542/v1/cd177bc5c19feb4dda3dc6e5.png"},{"id":21885456,"identity":"eb7161af-830f-412a-9fd3-66981db11f24","added_by":"auto","created_at":"2022-05-25 17:20:13","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":7541,"visible":true,"origin":"","legend":"\u003cp\u003e(A) Pseudo first-order kinetics with NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e removal, (B) Pseudo second-order kinetics with NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e removal\u003c/p\u003e","description":"","filename":"Onlinefloatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-1692542/v1/b4b23c1d84c790febedd3e78.png"},{"id":22270551,"identity":"75fbde38-52a7-428b-9a44-a366ba3e62f5","added_by":"auto","created_at":"2022-06-05 16:44:19","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":552022,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-1692542/v1/29e2d4c5-74b3-4c1e-a5c3-2e031f4d71c1.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Removal of Pollutants from Landfill Leachate by Adsorption with Nano Zero Valent Iron Particles (nZVI): Adsorption Isotherms and Kinetic Studies","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAdsorption is a significant treatment technology when used singly or in a combined treatment process to remove organic and inorganic substances (Kurniawan and Lo 2009; Oloibiri et al. 2017; Lee and Hur 2016; Kulikowska et al. 2014; Rodriguez et al. 2004). In recent years, nanoparticles (NPs) have been proposed as efficient adsorbents in the remediation of water and soil because of their unique atomic properties, higher reduction capacity, higher removal efficiency, magnetic property, non-toxic, molecular, and chemical properties compared to traditional adsorbents such as granulated -powdered and fibers activated carbons (GAC, PAC, ACF) (Yantasee et al. 2007; Chang et al. 2005; Liu et al. 2008; Hu et al. 2004; Yuan et al. 2010). All these properties can be used in the treatment of different types of wastewaters. The commonly used NPs for wastewater treatment are zero-valent metal nanoparticles, metal oxides nanoparticles, carbon nanotubes, and nanocomposites. Among them, the zero-valent iron nanoparticles (nZVI) have achieved very interesting and promising results for various pollutant remediation such as pesticides, polychlorinated hydrocarbons, chlorobenzenes, coloring agents, etc (Ghasemzadeh et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2014\u003c/span\u003e, Galdames et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Landfill leachate (LFL) is very strong wastewater and causes environmental concern due to the wide range of polluting parameters it contains. Landfill leachate is dark brown colored and odorous wastewater containing many suspended and dissolved organic substances, pathogenic substances, and toxic compounds such as heavy metals and heavy organic substances (Atmaca \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2009\u003c/span\u003e; Gotvajn et al. \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2009\u003c/span\u003e; Lou et al. \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). LFL treatment is very complicated, expensive, and generally requires a combination of various treatment processes (Bashir et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). Although several methods of LFL treatment are available, adsorption has been widely used as pre-treatment or post-treatment due to its simplicity and cost-effectiveness. Furthermore, the adsorption process of LFL by nano zero-valent iron is preferred comparatively with other treatment methods due to its high efficiency, ease of operation, and ability to treat wastewater treatment. Although different isotherm models have been developed to describe the sorption of several pollutants on nZVI, there has been very limited information on adsorption performance towards landfill leachate. Kashitarash et al. (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2012\u003c/span\u003e) reported fast removal efficiency of 47.94% for COD in 10 min at optimal conditions however sorption interactions onto nZVI particles have not been included in this study. Thus, for a deeper understanding of the LFL treatment and the related sorption interactions onto nZVI particles, the Langmuir and Freundlich isotherms have been considered in this study. Moreover, pseudo 1st order, pseudo 2nd order, kinetics models were applied to the sorption data for a deeper insight into the removal mechanism.\u003c/p\u003e \u003cp\u003eHence, the main objective of this study is to investigate the suitability of the selected isotherm and kinetic models in describing the treatment of LFL by nZVI. Besides, DOC, COD, NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e, NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e and color of LFL and the effect of pH, reaction time, and nZVI dosage variation were investigated to determine the optimum conditions.\u003c/p\u003e"},{"header":"Material And Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePreparation of nZVI\u003c/h2\u003e \u003cp\u003eThe nZVI was synthesized with dispersing agent, polyethylene glycol (PEG-4000). The basic principle of the synthesis was that ferrous ion was rapidly reduced to nZVI by borohydride solution according to the following reaction (Eq.\u0026nbsp;1) (He et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2012\u003c/span\u003e):\u003c/p\u003e \u003cp\u003eFe\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e\u003csub\u003e(aq)\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;2BH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e\u003csub\u003e(aq)\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;6H\u003csub\u003e2\u003c/sub\u003eO\u0026rarr;Fe\u003csup\u003e0\u003c/sup\u003e\u003csub\u003e(s)\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;2B(OH)\u003csub\u003e3(aq)\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;7H\u003csub\u003e2\u003c/sub\u003e\u0026uarr; (1)\u003c/p\u003e \u003cp\u003eIn this method; 1.7868 g FeSO\u003csub\u003e4\u003c/sub\u003e\u0026bull;7H\u003csub\u003e2\u003c/sub\u003eO was dissolved in 90 mL 4/1 (v/v) ethanol/deionized water mixture in a 500-mL bottle and then 0.3 g PEG-4000 was added into the above solution. The temperature was kept at 20\u0026deg;C. The solution was stirred at 220 rpm for 30 min to ensure that PEG-4000 was completely dissolved. Before reductant addition, the solution pH was adjusted to about 6.5 with 1 M NaOH. Then, 50 mL of 1.3883 g KBH\u003csub\u003e4\u003c/sub\u003e aqueous solution was added dropwise into the mixture at 220 rpm. The solution was stirred for another 30 min after the addition of all KBH\u003csub\u003e4\u003c/sub\u003e. Then the resulting black solid particles were washed with deoxygenated water three times and deoxygenated absolute ethanol twice and were collected by magnetic separation. Finally, the nZVI particles were dried at 70\u0026deg;C and stored in a under N\u003csub\u003e2\u003c/sub\u003e gas to prevent nZVI oxidation from atmospheric oxygen. In our previous work, synthesized nZVI characterization was carried out using XRD, SEM, and EDX techniques (Gocer et al. 2019).\u003c/p\u003e \u003c/div\u003e\u003cp\u003e\u0026nbsp;\u003cstrong\u003eLandfill Leachate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRaw LFL was collected from a municipal sanitary landfill located in Kahramanmaras, Turkey. The total amounts of LFL deposited daily were 815\u0026mdash;830tons. LFL was collected from the equilibration tank and stored at 4\u0026deg;C until used. The characteristics of raw LFL is summarized in Table 1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1\u003c/strong\u003e Landfill Leachate Characterization\u0026nbsp;\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellpadding=\"0\" cellspacing=\"0\" width=\"619\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.516962843295637%\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e\u003cstrong\u003eConcentration\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e\u003cstrong\u003eConcentration\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.516962843295637%\"\u003e\n \u003cp\u003eTotal Organic Carbon (DOC)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e7058\u0026plusmn;400(mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003eNO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e320\u0026plusmn;20(mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.516962843295637%\"\u003e\n \u003cp\u003eCOD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e16000\u0026plusmn;1500(mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003eNO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e670\u0026plusmn;40(mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.516962843295637%\"\u003e\n \u003cp\u003eBOD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e1500\u0026plusmn;300(mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003ePt-Co (Color unit)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e6380\u0026plusmn;300\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.516962843295637%\"\u003e\n \u003cp\u003eNH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e2120\u0026plusmn;200(mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003ePO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e-3\u003c/sup\u003e-P\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"26.494345718901453%\"\u003e\n \u003cp\u003e78\u0026plusmn;10(mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAdsorption experiments and capacity\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eThe effect of various parameters including pH (3\u0026ndash;8), contact time (15-330min), nZVI concentration (50\u0026ndash;500 mgFe\u003csup\u003e0\u003c/sup\u003e/L) was tested on NН\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e, NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e, DOC, and COD removal in batch adsorption experiments, for the evaluation of the optimum process conditions. (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e2\u003c/span\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 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eExperimental Plan\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"11\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"6\" rowspan=\"7\"\u003e \u003cp\u003eNano Zero Valent Iron (nZVI)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAdsorbent Concentration (mgFe\u003csup\u003e0\u003c/sup\u003e/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c8\" namest=\"c3\"\u003e \u003cp\u003epH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMixing Rate (rpm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eContact Time (min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eTemperature (\u003csup\u003eo\u003c/sup\u003eC)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003e15\u0026ndash;330\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003eRoom Temperature (25\u003csup\u003eo\u003c/sup\u003eC)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8\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 adsorption capacity, qe, (mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), and pollutants removal efficiency (%) of the tested nZVI were calculated by Eqs.\u0026nbsp;(\u003cspan refid=\"Equ1\" class=\"InternalRef\"\u003e2\u003c/span\u003e) and (\u003cspan refid=\"Equ2\" class=\"InternalRef\"\u003e3\u003c/span\u003e), respectively:\u003c/p\u003e\u003cp\u003e\u003cimg src=\"data:image/png;base64,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\"\u003e\u003c/p\u003e \u003cp\u003eIn Eqs.\u0026nbsp;(\u003cspan refid=\"Equ1\" class=\"InternalRef\"\u003e2\u003c/span\u003e) and (\u003cspan refid=\"Equ2\" class=\"InternalRef\"\u003e3\u003c/span\u003e), V is the volume of the leachate (L), W is the amount of adsorbent (g), Co and Ce are the initial and equilibrium concentrations of pollutants (mg L\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) in the leachate, respectively.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eAnalyses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll samples were centrifuged at 4000 rpm for 5 min (Eppendorf Centrifuge 5415R, Hamburg, Germany) and then, were filtered using a sterile syringe 0.45\u0026mu;m filter (Sartorius AG, Gottingen, Germany). DOC and TN concentrations were analyzed using a TOC instrument coupled with TN (Shimadzu TOC-VCPN, Kyoto, Japan). The pH was measured by a pH meter (Thermo, Orion 4 Star, Indonesia). Ionic composition of influent and effluent samples (ammonium, nitrate) was measured by ion chromatography (Dionex ICS-3000, Sunnyvale, CA, USA). The COD measurements were carried out according to the dichromate-closed reflux Colorimetric Method described in Standard Methods (Standard Methods, 5220 D). The color was analyzed as Pt-Co units. Pt-Co color measurements were performed spectrophotometrically at 465 nm during lab-scale studies.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eAdsorption Isotherms and Kinetics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Langmuir, Freundlich isotherms and pseudo 1st order, pseudo 2nd order kinetics models were selected to simulate the isotherm adsorption of nZVI in this work.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAdsorption kinetics\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eThe amount of nZVI absorbed on the pollutants was calculated using the following equation (Eq.\u0026nbsp;\u003cspan refid=\"Equ3\" class=\"InternalRef\"\u003e4\u003c/span\u003e):\u003cdiv id=\"Equ3\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ3\" name=\"EquationSource\"\u003e\n$${q}_{e}=\\left(Co-Ct\\right)*\\frac{V}{m}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e4\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere qe expresses the adsorption capacity (mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e); C\u003csub\u003e0\u003c/sub\u003e and Ct are pollutant concentrations (such as DOC, COD, NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e, and NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e) (mg L\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) at time 0 and t, respectively. V indicates the volume of solution (mL) and m is the mass of nZVI (g). Adsorption kinetic parameters are divided into two; these are expressed as pseudo-first-order equations (Ho, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2004\u003c/span\u003e) and pseudo-second-order equations (Azizian \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2004\u003c/span\u003e; Ho 2006).\u003c/p\u003e\u003cp\u003e\u003cstrong\u003ePseudo-first-order kinetics\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eThe so-called first-order equation (Lagergren's equation) is expressed as the adsorption of solid-liquid solutions based on the adsorption capacity of solids (Ho, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). The linear form of the so-called first-order model can be expressed by the following equation (Eq.\u0026nbsp;\u003cspan refid=\"Equ4\" class=\"InternalRef\"\u003e5\u003c/span\u003e):\u003cdiv id=\"Equ4\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ4\" name=\"EquationSource\"\u003e\n$$Log\\left(qe-qt\\right)=Logqe-\\left(\\frac{k1}{2.303}\\right)t$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e5\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere qe and qt (mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) are defined as the adsorption capacities at time t(h) at equilibrium, respectively.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003ePseudo-second order kinetics\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eThe pseudo-second-order kinetics are used to define chemical adsorption from liquid solutions (Azizian \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2004\u003c/span\u003e; Ho 2006). The linear expression of this kinetics is shown in Eq.\u0026nbsp;\u003cspan refid=\"Equ5\" class=\"InternalRef\"\u003e6\u003c/span\u003e below (Eqs.\u0026nbsp;\u003cspan refid=\"Equ5\" class=\"InternalRef\"\u003e6\u003c/span\u003e):\u003c/p\u003e\u003cp\u003e\u003cimg src=\"data:image/png;base64,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\"\u003e\u003c/p\u003e \u003cp\u003ewhere k\u003csub\u003e2\u003c/sub\u003e is the rate constant for pseudo-second-order adsorption (g mg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and k\u003csub\u003e2\u003c/sub\u003eqe\u003csup\u003e2\u003c/sup\u003e is the initial adsorption rate (mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e).\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eAdsorption isotherm models\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eFreundlich isotherm\u003c/h2\u003e \u003cp\u003eFreundlich isotherm models are valid for both monolayer (chemisorption) and multilayer adsorption processes. This isotherm is known adsorbing to the heterogeneous surface of an adsorbent. The linear form of the Freundlich equation is expressed as (Eq.\u0026nbsp;\u003cspan refid=\"Equ6\" class=\"InternalRef\"\u003e7\u003c/span\u003e):\u003cdiv id=\"Equ6\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ6\" name=\"EquationSource\"\u003e\n$$Lnqe=LnKF+\\frac{1}{n}LnCe$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e7\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere K\u003csub\u003eF\u003c/sub\u003e and n are Freundlich isotherm constants related to adsorption capacity and adsorption intensity, respectively and Ce is the equilibrium concentration (mg L\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) (Tan \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2009\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e\u003cp\u003e\u003cstrong\u003eLangmuir isotherm\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eThe Langmuir isotherm assumes monolayer adsorption on a single surface with a certain number of adsorption sites. After the adsorption zone is filled, no more tendency takes place. In this way, it will reach a saturation point where maximum adsorption of the surface will be achieved. The linear form of the Langmuir isotherm model is expressed as (Eq.\u0026nbsp;\u003cspan refid=\"Equ7\" class=\"InternalRef\"\u003e8\u003c/span\u003e):\u003cdiv id=\"Equ7\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ7\" name=\"EquationSource\"\u003e\n$$\\frac{Ce}{qe}=\\frac{Ce}{qmax}+\\frac{1}{KLqmax}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e8\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere K\u003csub\u003eL\u003c/sub\u003e is the Langmuir constant related to the energy of adsorption and qm is the maximum adsorption capacity (mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) (Barkat et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2009\u003c/span\u003e; Chingombe et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2006\u003c/span\u003e).\u003c/p\u003e"},{"header":"Results And Discussion","content":"\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eAdsorption Experiments and Capacities\u003c/h2\u003e \u003cp\u003eIn the adsorption experiments, optimum conditions were examined for different pH (3-4-5-6-7-8) and contact time (15-330min). In terms of COD, optimum conditions were determined at pH and contact time of 8 and 120 min, respectively. The highest COD removal efficiency was about 60%. After that, the effect of increasing zero-valued iron concentration (50\u0026ndash;500 mg/L, Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e2\u003c/span\u003e) on pollutant removal was tested at pH of 8 and contact time of 120min. Optimum zero-valent iron concentration was 50mg/L in terms of COD, DOC, NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e, and NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e, corresponding to removals of 75%, 60%, 57% and 33%, respectively. Figure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. shows the effect of increasing nZVI concentration on the adsorption capacity (qe). It was noticed the increase in nZVI from 50 to 500mg/L decreased the adsorption capacity of pollutants which may be attributed to the collection of the nanoparticles. According to Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e nZVI adsorption capacity for DOC, NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e and NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e were found to be 29.62 mg/g, 21.01 mg/g, and 3.12 mg/g at 50mg/L nZVI concentration, respectively. Adly et al. (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) reported that they investigated the removal of phosphorus adsorption on nanoscale zero-valent iron (nZVI)/activated carbon composite. They found that the maximum adsorption capacity at pH 4 was 53.76 mg/g. They obtained high adsorption capacity due to the use of nZVI and activated carbon (AC) as a support material. In another study, biochar prepared with nZVI and sewage sludge was used for arsenic removal from aqueous solutions. They found relatively higher adsorption capacity (60.61 mg/g) compared to our results which was probably due to the adverse effect of the strong and the complicated LFL (Liu et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eHalim et al. (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2010\u003c/span\u003e) reported that composite medium, zeolite, and activated carbon the adsorption capacities of 32.89 mg/g, 17.45 mg/g, and 6.08 mg/g respectively which is in good agreement with our study. Eljamal et al., (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) reported that nanoparticles have great potential for the practical applications of pollutants removal from wastewater. Unlike our study, according to the studies of Boparai et al. (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2011\u003c/span\u003e) nZVI particles reported removal of Cd\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;+\u0026thinsp;in the concentration range of 25\u0026ndash;450 mg/L. The maximum adsorption capacity of nZVI for Cd\u003csup\u003e2+\u003c/sup\u003e was determined as 769.2 mg/g. They reported that nZVI can be used as an efficient adsorbent for the removal of cadmium from polluted water sources.\u003c/p\u003e \u003c/div\u003e\u003cp\u003e\u003cstrong\u003eAdsorption Isotherms\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eAdsorption isotherms are a widely used method to determine the isotherm equilibrium condition of an adsorption system. Also this method; helps to decide the surface area of the adsorbent, the volume, size distribution of the pores, the temperature of adsorption, and the absorbability of a gas or vapor on the adsorbent. Adsorption of DOC, NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e, NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e by nZVI particles was modeled using the Freundlich and Langmuir isotherms with the quality of the fit assessed using the correlation coefficient (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Isotherm parameters in terms of dissolved organic carbon (DOC) are given in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e3\u003c/span\u003e below.\u003c/p\u003e \u003cp\u003e \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 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAdsorption Isotherms Parameters (DOC parameter)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"7\" nameend=\"c8\" namest=\"c2\"\u003e \u003cp\u003eLangmuir Isotherms\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003eFreundlich Isotherms\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAdsorbent\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eConcentration (mg/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eSlope\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eq\u003c/b\u003e\u003csub\u003e\u003cb\u003emax\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e.\u003cb\u003eCe\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003eqe\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003eSlope\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eF\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003en\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,0756\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3,25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13,22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00056\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9931\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1765,95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e13,22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-0,9014\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,574\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-1,109\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9927\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,7835\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3,64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1,276\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00013\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,971\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7211,41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1,276\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-3,2661\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,261\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,306\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9866\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1,6968\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,276\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,588\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00011\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9573\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7211,41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0,588\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-3,3491\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,173\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,298\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9799\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,4893\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5,12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2,04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0022\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9669\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e448,224\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2,04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-2,9702\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2,341\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,342\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9858\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,2328\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4,339\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,447\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00017\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9839\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5787,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0,447\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2,6268\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9922\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3,2552\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1,83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,307\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00015\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,923\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6555,25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0,307\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-2,735\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,015\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,365\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9632\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 slope and intercept of plots of Ce/qe versus Ce, at adsorbent concentration, were used to calculate qm and K\u003csub\u003eL\u003c/sub\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA). The size of qmax and K\u003csub\u003eL\u003c/sub\u003e indicates high adsorption capacity (50mg/L adsorption concentration, Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e3\u003c/span\u003e). If K\u003csub\u003eL\u003c/sub\u003eCe\u0026thinsp;\u0026lt;\u0026thinsp;\u0026lt;\u0026thinsp;1; It is observed that adsorption is low and K\u003csub\u003eL\u003c/sub\u003eCe\u0026thinsp;\u0026gt;\u0026thinsp;\u0026gt;\u0026thinsp;1 is high. When the table above is evaluated, it is observed that K\u003csub\u003eL\u003c/sub\u003eCe is \u0026gt;\u0026thinsp;\u0026gt;\u0026thinsp;1 and the amount of adsorption is high. If the R\u003csub\u003eL\u003c/sub\u003e value is greater than 1, the adsorption process is inconvenient, it is linear if it is equal to 1, it is convenient if it is between 0 and 1, and it is irreversible if it is 0 (Eq.\u0026nbsp;\u003cspan refid=\"Equ6\" class=\"InternalRef\"\u003e7\u003c/span\u003e). When the Langmuir isotherm is examined, it is observed that the R\u003csub\u003eL\u003c/sub\u003e value is between 0 and 1 (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The Freundlich isotherm constants K\u003csub\u003eF\u003c/sub\u003e and n are determined from the intercept and slope of a plot of Lnqe versus LnCe (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). It is 1/n from the slope of the LnCe graph against Lnqe and LnK\u003csub\u003eF\u003c/sub\u003e from the cutting point of the y axis (Eq.\u0026nbsp;\u003cspan refid=\"Equ5\" class=\"InternalRef\"\u003e6\u003c/span\u003e). The high LnK\u003csub\u003eF\u003c/sub\u003e and n values show that sorbent has a high tendency to adsorption and adsorption capacity. The value of 1/n ranging from 0 to 1 is expressed as a measure of an adsorption tendency and heterogeneity that becomes heterogeneous as it approaches zero. 1/n\u0026thinsp;\u0026lt;\u0026thinsp;1 indicates compatibility with Langmuir isotherm and 1/n\u0026thinsp;\u0026gt;\u0026thinsp;1 indicates compatibility with adsorption condition. As a result, it is observed that the DOC removal adapts to the Langmuir isotherm. The best adsorption capacity suitable for the Langmuir isotherm occurred at a concentration of 50 mg /L nZVI (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.9931). Langmuir isotherm parameter fits (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e3\u003c/span\u003e) for DOC removal efficiency adsorption on nZVI yielded isotherms that were in good agreement with observed behavior (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;\u0026ge;\u0026thinsp;0.99). Maamoun et al. (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) investigated the suitability of various adsorption isotherms and kinetic models to explain the removal of phosphorus (P) from aqueous solutions by nanoscale zero-valent-iron (nZVI). They found that the Langmuir isotherm and the pseudo-second-order kinetic model are the best models with the highest linear and nonlinear correlation (R\u003csup\u003e2\u003c/sup\u003e). Similarly; in another study, the adsorption capacity of synthesized modified adsorbent (nZVI/AC) for arsenite and arsenate at pH 6.5 was calculated from Langmuir adsorption isotherms in batch experiments was 18.2 and 12.0 mg/g, respectively. It can be concluded that nZVI without the use of support material reached the similar results due to the its positive effect (Zhu et al. \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). Adsorption of NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e by nZVI particles was modeled using the Freundlich and Langmuir isotherms with the quality of the fit assessed using the correlation coefficient (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA-B). Isotherm parameters in terms of NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e removal efficiency is given in Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e4\u003c/span\u003e below.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAdsorption Isotherms Parameters (NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e parameter)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"7\" nameend=\"c8\" namest=\"c2\"\u003e \u003cp\u003eLangmuir Isotherms\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003eFreundlich Isotherms\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAdsorbent Concentration (mg/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eSlope\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eq\u003c/b\u003e\u003csub\u003e\u003cb\u003emax\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e.\u003cb\u003eCe\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003eqe\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003eSlope\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eF\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003en\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,5935\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1,82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1,67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0045\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9999\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e220,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1,67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-0,8096\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-1,23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9999\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,5769\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1,78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1,73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9999\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e211,82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1,73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-0,781\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,264\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-1,28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9999\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,6166\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1,84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1,62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9999\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e231\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1,62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-0,8412\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,253\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-1,18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9999\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,6166\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1,84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1,62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9999\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e234\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1,62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-0,8412\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,253\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-1,18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9999\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,6367\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\u003e1,57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9994\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e234,24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1,57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-0,8688\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,256\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-1,151\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9993\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1,0433\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2,43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,958\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0024\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9995\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e400,95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0,958\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-1,3999\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,181\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9996\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\u003eIt was observed that NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e removal is fitted to the Freundlich isotherm (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eB). Additionally, K\u003csub\u003eL\u003c/sub\u003eCe is \u0026gt;\u0026thinsp;\u0026gt;\u0026thinsp;1 and the amount of adsorption is high. According to Langmuir isotherm, it was observed that the R\u003csub\u003eL\u003c/sub\u003e value is between 0 and 1 (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e4\u003c/span\u003e) confirming Langmuir isotherm is suitable NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e removal. The high LnK\u003csub\u003eF\u003c/sub\u003e and n values show that sorbent has a high tendency for high adsorption capacity. Unlike our study, Kanel et al. (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2005\u003c/span\u003e) investigated arsenic removal efficiency in groundwater by using nZVI as an adsorbent and observed 3.5 mg As(III)/g adsorption capacity with Freundlich isotherm. Other studies using new composite materials for landfill leachate treatment found different results. Langmuir and Freundlich reported that the isotherm's regression coefficients (R\u003csup\u003e2\u003c/sup\u003e) for COD and ammonia nitrogen were 0.9971 and 0.9914, respectively (Detho et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Hassemi et al. (2021) investigated ammonium removal efficiency from landfill leachate (LL) using montmorillonite/hematite nanocomposite (M/HNC). They reported that the ammonium adsorption data on the nanoparticle material agreed with the Langmuir isotherm models. Isotherm parameters in terms of NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e removal efficiency are given in Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e5\u003c/span\u003e below.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAdsorption Isotherms Parameters (NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e parameter)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"7\" nameend=\"c8\" namest=\"c2\"\u003e \u003cp\u003eLangmuir Isotherms\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003eFreundlich Isotherms\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAdsorbent Concentration (mg/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eSlope\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eq\u003c/b\u003e\u003csub\u003e\u003cb\u003emax\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eL\u003c/b\u003e\u003c/sub\u003e.\u003cb\u003eCe\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003eqe\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003eSlope\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003eK\u003c/b\u003e\u003csub\u003e\u003cb\u003eF\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003en\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,2399\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3,56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4,16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00013\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9725\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7298\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4,16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-2,7844\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,421\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,359\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9872\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,7312\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4,8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1,36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9899\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e11942,4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1,36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-3,7169\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,276\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,269\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9959\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1,5718\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4,95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,636\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9944\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e12300,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0,636\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-3,9212\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,158\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,255\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9978\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,6273\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5,31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,00007\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9949\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e13142,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0,38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-4,1943\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,094\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,238\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9981\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,2266\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3,8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,449\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9737\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9541,8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0,449\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-3,0823\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,074\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,324\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9881\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,9092\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3,83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,343\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,9747\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9720,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0,343\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-3,1881\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1,037\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0,313\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0,9905\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\u003e \u003c/p\u003e \u003cp\u003eIn terms of NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e removal efficiency and zero-valued iron concentration, it was observed that it fits to the Freundlich isotherm (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB). The size of qmax and K\u003csub\u003eL\u003c/sub\u003e in Langmuir isotherm indicates high adsorption capacity (Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e5\u003c/span\u003e). When all these results were examined; Langmuir and Freundlich isotherm equations are created upon ammonium removal and with increasing adsorbent concentrations. These results showed that the optimum conditions for adsorption capacity and isotherms were at 50 mg/L nZVI (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.9). Mittal (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) used chicken feathers as an adsorbent for the removal of toxic substances containing dye waters. They found adsorption data, Langmuir and Freundlich confirmed with adsorption isotherm models. According to our study, similar results were obtained in terms of both removal efficiency and adsorption isotherms. In another study, the adsorption capacities of As(III) and As(V) were obtained as 35.83 mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 29.04 mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, respectively, as determined from Langmuir adsorption isotherms in batch experiments (Wang et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). When compared with our study, it is seen that the adsorption capacity is high. Similarly; in another study, lead and cadmium adsorption efficiency from leachate by the natural zeolite clinoptilolite was investigated and they found best isotherm model for lead adsorption fits the Freundlich model, while for cadmium it fits the Langmuir model (Farai et al. 2021).\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eAdsorption Kinetics\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eThe adsorption rate is a vital parameter to assess the efficiency of an adsorbent for the removal of contaminates. The adsorption of nitrate (NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e), ammonium (NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e), and dissolved organic carbon (DOC) onto the nZVI was explained through pseudo-first-order and pseudo-second-order kinetic models. Pseudo-first-order kinetic model examines the change in adsorption capacity depending on time. Kinetics parameters in terms of dissolved organic carbon (DOC), nitrate (NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e), and ammonium (NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e) removal efficiency are given in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e-\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eA-B. k\u003csub\u003e1\u003c/sub\u003e and qe, at the adsorbent concentration evaluated experimentally, were calculated using the slope and intercept of plots of log(qe\u0026thinsp;\u0026minus;\u0026thinsp;qt) versus t (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eA, Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e6\u003c/span\u003e), (Eq.\u0026nbsp;\u003cspan refid=\"Equ3\" class=\"InternalRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Equ4\" class=\"InternalRef\"\u003e5\u003c/span\u003e). Pseudo-second-order adsorption parameters qe and k\u003csub\u003e2\u003c/sub\u003e in Eq.\u0026nbsp;(\u003cspan refid=\"Equ4\" class=\"InternalRef\"\u003e5\u003c/span\u003e) were determined by plotting t/qt versus t (Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab7\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAdsorption Kinetics Parameters (DOC parameter)\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\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003ePseudo-first-order kinetics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cp\u003ePseudo-second-order kinetics\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAdsorbent Concentration (mg/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eSlope (k\u003c/b\u003e\u003csub\u003e\u003cb\u003e1\u003c/b\u003e\u003c/sub\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eqe (mg/mg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eSlope (qe)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003ek\u003c/b\u003e\u003csub\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0,0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0364\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0114\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0009\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0009\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9233\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0,0003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0324\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0073\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9673\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0,0008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,033\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,00594\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9673\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,0017\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0336\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,2662\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,973\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,0013\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0336\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,2487\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9853\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,0027\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0333\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,3835\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0007\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9656\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\u003eR\u003csup\u003e2\u003c/sup\u003e value in the adsorption kinetics equation; considering the adsorbent concentration and DOC removal efficiency, it is observed that the R\u003csup\u003e2\u003c/sup\u003e value is very close to 1 in the pseudo-second-order adsorption kinetic equation (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.9853, 400mg/L Fe\u003csup\u003e0\u003c/sup\u003e), (Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e6\u003c/span\u003e). However, DOC was complied with pseudo-second-order adsorption kinetics (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eB-Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e6\u003c/span\u003e). These results show that pseudo-second-order kinetics are adsorbed onto the nZVI surface via chemical interaction. Foul et al. (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2009\u003c/span\u003e) investigated the removal efficiency of landfill leachate using two different adsorbents (activated carbon and limestone). Adsorption kinetics, on the other hand, determined their suitability to the pseudo-second-order kinetic model. Similarly, Boparai et al. (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2011\u003c/span\u003e) used nZVI particles to investigate the removal of Cd\u003csup\u003e2+\u003c/sup\u003e (25\u0026ndash;450 mg L\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e ). They observed that the adsorption kinetics was well adapted using a pseudo-second-order kinetic model. In another study, they aimed to achieve both anionic and cationic dye removal efficiency by using a zero-valent-iron loaded composite nanoparticle material. The adsorption process of both dyes was well fitted with the Langmuir isotherm model and pseudo-second-order kinetic model (Eltaweil et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab8\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAdsorption Kinetics Parameters (NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e parameter)\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\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003ePseudo-first-order kinetics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cp\u003ePseudo-second-order kinetics\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAdsorbent Concentration (mg/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eSlope (k\u003c/b\u003e\u003csub\u003e\u003cb\u003e1\u003c/b\u003e\u003c/sub\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eqe (mg/mg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eSlope (qe)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003ek\u003c/b\u003e\u003csub\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0259\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,2654\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0082\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0082\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9995\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,026\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0083\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0083\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9991\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0258\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0449\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9994\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0258\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0449\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9994\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0259\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0511\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0079\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,991\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0,0002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0246\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,3195\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0061\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0062\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9974\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 rate parameters of these adsorption kinetic models listed in Table\u0026nbsp;\u003cspan refid=\"Tab8\" class=\"InternalRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Tab9\" class=\"InternalRef\"\u003e8\u003c/span\u003e indicate that adsorption of ammonia and nitrate from aqueous solution on nZVI obeys the pseudo-second-order kinetic model according to R\u003csup\u003e2\u003c/sup\u003e (\u0026gt;\u0026thinsp;0.99) (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). Previous studies have reported that the adsorption of ammonia on zeolite obeys the pseudo-second-order model (Doğan et al. 2006; Lei et al. \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). Genethliou et al. (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) used natural zeolite for the removal of pollutants in raw landfill leachate. They reported that mostly followed the linear pseudo-second-order model with the isotherm and kinetic conformity they obtained, NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-N adsorption. In another study, used activated biochar-loaded nano-zero iron (A-BC-NZVI) to remove uranium from wastewater. They found that it complies with the pseudo-second-order equation and the maximum U(VI) adsorption amount of the Langmuir model at pH 6.0 was 331.13 mg/g (Zhang et al. \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab9\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 8\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAdsorption Kinetics Parameters (NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e parameter)\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\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003ePseudo-first-order kinetics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cp\u003ePseudo-second-order kinetics\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAdsorbent Concentration (mg/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eSlope (k\u003c/b\u003e\u003csub\u003e\u003cb\u003e1\u003c/b\u003e\u003c/sub\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eqe (mg/mg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eSlope (qe)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003ek\u003c/b\u003e\u003csub\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003eR\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,0018\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0018\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,07231\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,989\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,0005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0333\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0647\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9946\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0329\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0051\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9983\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0328\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0218\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9989\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0,0003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0334\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,021\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9895\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0,0002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,0332\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,0143\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0,0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0,9875\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\u003e \u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eNano zero-valent iron (nZVI) can be used as an effective adsorbent for removing COD, DOC, NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e and NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e from landfill leachate. Equilibrium isotherms in this study were analyzed using Langmuir and Freundlich. Kinetic data were obtained and analyzed using pseudo 1st and pseudo 2nd equations. Optimum conditions were determined as pH 8, reaction time 120 minutes, and adsorbent dose 50mg/L nZVI. COD, DOC, NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e and NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e removal efficiency was approximately 75%, 60%, 57% and 33%, respectively. DOC, NH\u003csub\u003e4\u003c/sub\u003e \u003csup\u003e+\u003c/sup\u003e and NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e adsorption capacities, respectively; It was found to be 29.62 mg/g, 21.01 mg/g and 3.12 mg/g. The experimental results were applied to isotherms commonly used in landfill leachate and the most suitable isotherm was found to be Langmuir. As a result of administering the experimental data to kinetic equation, the mechanism controlling the rate was determined and the most suitable model was found to be the pseudo 2nd equation. Results from this study suggest that nZVI is a very effective adsorbent for pollutants, as anticipated. Sorption kinetics is investigated to develop an understanding of controlling reaction pathways and the mechanisms of sorption reactions. In near future, nanoparticles may turn out to be the essential and indispensable components of water purification and treatment systems and facilities. Further research can be focused on improving the functional properties of nanoparticles to meet the versatile needs in both the detection and treatment of pollutants.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eCompeting interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis article was supported by the Scientific Research Unit of the \u0026Ccedil;ukurova University. Project No: FDK-2019-11782.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAdly A, Mostafa NG, Elawwad A et al (2022) Adsorption of phosphorus onto nanoscale zero-valent iron/activated carbon: removal mechanisms, thermodynamics, and interferences Journal of Water Reuse and Desalination.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAtmaca E (2009) Treatment of landfill leachate by using electro-Fenton method J Hazard Mater 163(1):109\u0026ndash;114.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAzizian S (2004) Kinetic models of sorption: a theoretical analysis J. Colloid Interface Sci 276, 47\u0026ndash;52.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarkat M, Nibou D, Chearouche S, Mellah A et al (2009) Kinetics and thermodynamics studies of chromium(VI) ions adsorption onto activated carbon from aqueous solutions Chem. Eng. 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Mater. 172, 1591\u0026ndash;1596.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Zero Valent Iron, Landfill Leachate, Adsorption, Equilibrium Isotherms, Kinetics ","lastPublishedDoi":"10.21203/rs.3.rs-1692542/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-1692542/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eNano zero-valent iron (nZVI) is an effective adsorbent for removing various organic and inorganic contaminants. In this study, nZVI particles, synthesized in our previous work, were used for landfill leachate pre-treatment. The adsorption performance was tested at various adsorbent concentrations (50-500mg Fe\u003csup\u003e0\u003c/sup\u003e/L), pH (3\u0026ndash;8), and contact times (15-330min). Chemical Oxygen Demand (COD), Dissolved Organic Carbon (DOC), Nitrate (NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e) and Ammonium (NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e) removal efficiency was approximately 75%, 60%, 57%, and 33%, respectively. The obtained data were fitted well by the Langmuir isotherm and adsorption kinetics of pseudo-second-order equations (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.9). The adsorption capacities were found to be 29.62mg/g, 21.01mg/g, and 3.12mg/g, for DOC, NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e, and NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e respectively at Fe\u003csup\u003e0\u003c/sup\u003e concentration of 50mg Fe\u003csup\u003e0\u003c/sup\u003e/L, pH of 8, and contact time of 120min which was determined as the effective operational conditions in this work. The obtained removal levels were higher compared to the conventional activated carbon adsorption (72.3%). Results suggest that nZVI has the potential to create effective adsorption relevant to landfill leachate pre-treatment thereby providing more efficient biological treatment by decreasing important pollutants before biological treatment.\u003c/p\u003e","manuscriptTitle":"Removal of Pollutants from Landfill Leachate by Adsorption with Nano Zero Valent Iron Particles (nZVI): Adsorption Isotherms and Kinetic Studies","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-05-25 17:20:11","doi":"10.21203/rs.3.rs-1692542/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3ce019fe-dbe0-4a5e-aadf-178182d321b9","owner":[],"postedDate":"May 25th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2022-06-05T16:44:15+00:00","versionOfRecord":[],"versionCreatedAt":"2022-05-25 17:20:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-1692542","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-1692542","identity":"rs-1692542","version":["v1"]},"buildId":"WrCJVZZCHTDjtuVLN7oU0","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}