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Öğe Abatement of nitrous oxide over natural and iron modified natural zeolites(ELSEVIER SCIENCE BV, 2011) Ates, Ayten; Reitzmann, Andreas; Hardacre, Christopher; Yalcin, HuseyinThe natural zeolite obtained from the Sivas-Yavu region in Turkey and iron modified forms were studied for the decomposition of N(2)O and selective catalytic reduction of N(2)O with NH(3). The natural and iron modified zeolites were characterised by XRD, SEM, H(2)-TPR, NH(3)-TPD and low temperature nitrogen sorption. The effect iron loading, precursor and valency on the catalytic performance of catalysts were studied. The catalytic activity of the zeolites increased up to about 7.0 wt.% Fe. Above this value, the activity decreased as a result of a reduction in the surface area and pore volume of the zeolite. The highest catalytic activity was observed using catalysts prepared with FeCl(2) due to the formation of more reducible iron species in the zeolites. When FeSO(4) was used as the iron precursor, sulphate remained on the surface even after extensive washing resulting in a decrease in the N(2)O decomposition activity and a shift the N(2)O reduction temperature to higher values. Since the natural and iron exchanged natural zeolites prepared using FeCl(2) have comparable activity with synthetic zeolites, the offer a promising alternative catalyst for the abatement of N(2)O, particularly for the selective reduction of N(2)O with NH(3). (C) 2011 Elsevier B.V. All rights reserved.Öğe Adsorption and column flotation studies on talc using anionic and cationic collectors(SPRINGER, 2010) Kursun, Hulya; Ates, AytenAdsorption properties and column flotation were studied to investigate the interaction of the anionic and cationic collectors and flotation recoveries for talc mineral. Adsorption capacity is dependent on pH, adsorption time, temperature, collector concentration, and particle size. Langmuir adsorption model was suitable for describing isotherms. Analyses were carried out using UV spectrometry. In this study, we analyzed some parameters affecting column flotation performance. It was determined that adsorption capacity, especially, had an important role in column flotation enrichment.Öğe Characteristics of Fe-exchanged natural zeolites for the decomposition of N2O and its selective. catalytic reduction with NH3(ELSEVIER SCIENCE BV, 2007) Ates, AytenNatural zeolites obtained from various regions of Turkey and their iron-exchanged forms were characterised by XRD, BET, H-2-TPR and NH3-TPD methods. Transient experiments with N2O showed that the iron introduced into natural zeolites have appreciable oxygen deposition capacity due to isolated iron species involved. Atomic surface oxygen species in these zeolites are formed at 250 degrees C, which is released through increasing the temperature until 900 degrees C, similar to Fe-containing ZSM-5 zeolite. The steady-state experiments indicate that the iron-containing zeolite of the Yavu-Sivas region, in particular, has high activity in selective catalytic reduction of N2O With NH3 as a consequence of isolated cationic and/or dimeric iron content. (C) 2007 Elsevier B.V. All rights reserved.Öğe Characterization of persimmon fruit peel and its biochar for removal of methylene blue from aqueous solutions: thermodynamic, kinetic and isotherm studies(Taylor & Francis Inc, 2020) Ates, Ayten; Oymak, TulayThe persimmon fruit peel (PFP) and its biochar (PFP-P) were evaluated for removal of methylene blue (MB) from aqueous solutions and characterized in detail. The pyrolysis of the PFP improved carbon content, surface area, and surface electronegativity of the biochar produced. The effect of initial solution pH, initial MB concentration, contact time, and temperature on the biosorption efficiency of MB on the PFP was investigated through the biosorption experiments in a batch system. The PFP showed higher biosorption removal efficiency than PFP-P due to the existence of hydroxyl and carboxyl functional groups. The maximum biosorption capacity of the PFP was found using 2 g/L of the adsorbent, at a contact time of 180 min and pH of 7. The adsorption kinetics and equilibrium isotherms were well represented by the pseudo-second-order model and the Langmuir model, respectively. The maximum biosorption capacity obtained from the Langmuir isotherm model was 303 mg g(-)(1). Also, the PFP showed an efficient removal efficiency for removal of MB in tap water, seawater, and river water. The high MB biosorption capacity of PFP can be a promising alternative for cationic dye removal at neutral pH.Öğe Direct co-deposition of binder-free Cu-biochar-based nonenzymatic disposable sensing element for electrochemical glucose detection(Elsevier, 2023) Larasati, Lucyana D.; Ates, Ayten; Oskay, Kursad OguzThis work is the first attempt to incorporate biochar on a pencil graphite electrode via one-step electrodeposition as a rational route for refining a copper-based biosensor for a high-performance nonenzymatic electrochemical glucose sensor. Biochar undecorated electrode counterpart was also fabricated for comparison. The cyclic voltammetry graph showed that co-deposition with biochar enhanced the electrocatalytic activity toward glucose oxidation in an alkaline medium. The surface morphology of the copper-biochar hybrid coating demonstrated an attractive three-dimensional structure that had not been reported in the literature. The results indicated that the supplied extending surface area due to biochar modification was the controlling factor for the improved electrochemical reactivity for glucose sensing. The amperometric analysis at an optimum potential of +0.70 V showed linear detection ranges from 0.8 & mu;M to 1 mM and from 1 mM to 5 mM, and good characteristics, such as high sensitivity (6214.4 & mu;A mM-1 cm-2), low limit of detection (0.8 & mu;M), a fast response time (less than 2 s), and excellent anti-interference capability toward the oxidation of glucose. The cost-effective and facile fabrication suggests that the prepared glucose-sensing element can be potentially adapted for construction as a disposable.Öğe Effect of alkali-treatment on the characteristics of natural zeolites with different compositions(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2018) Ates, AytenA series of natural zeolites with different compositions were modified by post-synthesis modification with sodium hydroxide (NaOH) solution. Natural and modified zeolites were characterized by XRD, SEM, nitrogen adsorption, FTIR, zeta potential and temperature programmed desorption of ammonia (NH3-TPD). The adsorption capacities of these samples were evaluated by the adsorption of manganese from aqueous solution. The treatment with NaOH led to a decrease in the surface area and microporosity of all natural zeolites as well as partly damage of the zeolite structure depending on zeolite composition. In addition, the amount of weak, medium and strong acid sites in the zeolites was changed significantly by NaOH treatment depending on zeolite composition. The NaOH treatment resulted in a four-fold improvement in adsorption capacity of natural zeolite originated from Bigadic and a twofold decrease in that of the natural zeolite originated from Manisa-Gordes. Although the improved adsorption capacity might be mainly due to modification of porosity in the zeolites and formation of hydroxysodahte, the reduced adsorption capacity of the zeolite might be mainly due to a significant deformation of the zeolite structure. The pseudo-second-order kinetic model for the adsorption of manganese on all natural and modified zeolites fits well. (C) 2018 Elsevier Inc. All rights reserved.Öğe Effect of Catalyst Modification on Hydrodealkylation of Aromatic Mixtures(Gazi Univ, 2022) Ates, Ayten; Yeniova, Hasip; Alibeyli, RafigHydrodealkylation of mesitylene in the presence of n-decane to benzene, toluene, and xylenes (BTX) over the promoted Cr-Al2O3 was studied. The effect of reaction temperature, WHSV, impregnation type, and amount of Cr and promoters such as V, Cs, Ni, and Mo on the stability and activity of Cr-Al2O3 was investigated. The addition of n-decane to mesitylene accelerated the hydrodealkylation activity of Cr-Al2O3 because of the formation of methyl- and ethyl-radicals. The catalyst modified with V and Cs (V-Cs-Cr-Al2O3) has a comparable performance with the commercial catalyst Pyrotol (Houdry, USA) in terms of stability, product selectivity, and reactant conversions.Öğe Effect of pre-treatment and modification conditions of natural zeolites on the decomposition and reduction of N2O(SPRINGER, 2015) Ates, AytenThe decomposition of N2O and reduction of N2O with NH3 on natural and modified zeolites were studied by a steady state reaction. Two different natural zeolites having different phase compositions were modified by ion exchange (0.5 M NH4NO3) and acid leaching (1 M HCl) and treated under low temperature, high temperature and steam conditions. It was observed that the surface modification of natural zeolites depends strongly on their structure and composition. The modification of zeolites by ion exchange and acid leaching increases the decomposition activity of N2O because of the formation of isolated iron and Fe-O-Al species. However, these modifications insignificantly affect the reduction of N2O with NH3. High temperature and steam treatments lead to dealumination, loss of crystallinity, sintering of phases and the formation of amorphous material in zeolites, resulting in a significant decrease in the decomposition and reduction activity of N2O. The kinetic evaluation for N2O decomposition predicts that the rate-limiting step is the recombinative desorption of molecular oxygen.Öğe The effect of various treatment conditions on natural zeolites: Ion exchange, acidic, thermal and steam treatments(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2012) Ates, Ayten; Hardacre, ChristopherTwo different natural zeolites having different phase compositions were obtained from different regions of Turkey and modified by ion-exchange (0.5 M NH4NO3) and acid leaching using 1 M HCl. The natural and modified samples were treated at low temperature (LT), high temperature (HT) and steam (ST) conditions and characterised by XRF, XRD, BET, FTIR, DR-UV-Vis, NH3-TPD and TGA. Ion-exchange with NH4+ of natural zeolites results in the exchange of the Na+ and Ca2+ cations and the partial exchange of the Fe3+ and Mg2+ cations. However, steam and acidic treatments cause significant dealumination and decationisation, as well as loss of crystalline, sintering of phases and the formation of amorphous material. The presence of mordenite and quartz phases in the natural zeolites increases the stability towards acid treatment, whereas the structure of clinoptilolite-rich zeolites is mostly maintained after high temperature and steam treatments. The natural and modified zeolites treated at high temperature and in steam were found to be less stable compared with synthetic zeolites, resulting in a loss of crystallinity, a decrease in the surface area and pore volume, a decrease in the surface acidity as well as dealumination, and decationisation. (C) 2012 Elsevier Inc. All rights reserved.Öğe Estimation of specific surface area and higher heating value of biochar and activated carbon produced by pyrolysis and physico-chemically assisted pyrolysis of biomass using an artificial neural network (ANN)(Springer Heidelberg, 2025) Balde, Mamadou Saliou; Karakis, Rukiye; Ates, AytenThe physical and chemical activation of biomass prior to pyrolysis significantly affects the properties of the activated carbon produced. In this study, raw tea waste (TW) and hazelnut shells (HS) were used to produce biochar and activated carbon samples by pyrolysis at different pyrolysis temperatures with and without chemical and physical activation. Subsequently, an artificial neural network (ANN) was developed based on the pyrolysis conditions, proximate and elemental analyses of the biomass feedstocks and the obtained biochar and activated carbon to predict the higher heating value (HHV) and specific surface area (SSA) of the biochar. For this purpose, machine learning algorithms such as ANN, Gaussian process regression (GPR), regression trees (RT), and support vector machines (SVM) were compared to find the best-performing algorithm for the prediction of HHV and SSA of biochar. Algorithms based on ANNs performed better than SVM, RT, and GPR models, with higher regressions and lower prediction errors. The resilient backpropagation (RProp) algorithm proved to be the most suitable training algorithm as it provided satisfactory results with a low percentage of mean squared error (MSE) and mean absolute error (MAE). The ANN models showed moderate to strong performance in the tests, with correlation coefficient (R) values of 0.82 and 0.95, coefficient of determination (R2) values of 0.67 and 0.90, and low MAE and MSE, indicating reasonable prediction accuracy for HHV and SSA of the biochar. The energy efficiency of biochar produced with conventional pyrolysis ranged from 9.84% to 21.13%, while the energy efficiency of activated carbon ranged from 45.26% to 67.21%, with the maximum reached at 300 degrees C. Based on the results of the thermodynamic analysis, it was found that the energy and exergy yields of the biochar and activated carbon produced depend on the activation conditions and temperature.Öğe Evaluation of iron containing biochar composites prepared by different preparation methods for H2O2 sensing(Elsevier, 2023) Ates, Ayten; Oskay, Kursad OguzBackground: The procedures employed to prepare the ferrous biochar samples, the iron salts utilized, and their quantities have an effect on the surface characteristics of the material and the types of iron that will develop on the surface.Methods: Iron containing biochar (Fe-BC) samples were prepared using three different preparation methods: Precipitation, Impregnation (IP) and Solid-state (SS). The iron content of the biochar (BC) was varied in a range from 6.5 to 21.0 wt. % by using a SS method that mechanically mixed FeCl3 and hazelnut shell (HS) in solid form.Significant Findings: The XRD, XPS and FT-IR results showed that the magnetite particles (Fe3O4) were mainly formed on the surface of all samples, but their content was strongly dependent on the preparation method and the amount of iron. Additionally, the formation of Fe2O3, Fe2C, FeCO3, and FeOOH species on the surface was determined. The highest surface area and microporosity were obtained for the Fe-BC sample prepared by IP (FeBC-IP):850 m2/g and 0.28 cm3/g, respectively. A novel and fast electrochemical sensing platform for the detection of H2O2 with a broad linear range (0.5-10 mM) and high sensitivity (621 mu A mM-1 cm-2) was fabricated. The findings demonstrate that the non-enzymatic BC-IP sensor is a useful alternative for measuring H2O2.Öğe Experimental and Computational Evaluation of Heavy Metal Cation Adsorption for Molecular Design of Hydrothermal Char(Mdpi, 2020) Delahaye, Louise; Hobson, John Thomas; Rando, Matthew Peter; Sweeney, Brenna; Brown, Avery Bernard; Tompsett, Geoffrey Allen; Ates, AytenA model hydrochar was synthesized from glucose at 180 degrees C and its Cu(II) sorption capacity was studied experimentally and computationally as an example of molecular-level adsorbent design. The sorption capacity of the glucose hydrochar was less than detection limits (3 mg g(-1)) and increased significantly with simple alkali treatments with hydroxide and carbonate salts of K and Na. Sorption capacity depended on the salt used for alkali treatment, with hydroxides leading to greater improvement than carbonates and K(+)more than Na+. Subsequent zeta potential and infrared spectroscopy analysis implicated the importance of electrostatic interactions in Cu(II) sorption to the hydrochar surface. Computational modeling using Density Functional Theory (DFT) rationalized the binding as electrostatic interactions with carboxylate groups; similarly, DFT calculations were consistent with the finding that K(+)was more effective than Na(+)at activating the hydrochar. Based on this finding, custom-synthesized hydrochars were synthesized from glucose-acrylic acid and glucose-vinyl sulfonic acid precursors, with subsequent improvements in Cu(II) adsorption capacity. The performance of these hydrochars was compared with ion exchange resins, with the finding that Cu(II)-binding site stoichiometry is superior in the hydrochars compared with the resins, offering potential for future improvements in hydrochar design.Öğe Experimental techniques for investigating the surface oxygen formation in the N2O decomposition on Fe-MFI zeolites(ELSEVIER SCIENCE SA, 2007) Ates, Ayten; Reitzmann, AndreasSeveral experimental techniques were used to investigate the formation of surface oxygen in the N2O decomposition on an Fe-MFI zeolite. These techniques consisted of multipulse and step experiments as transient methods at ambient pressure and experiments in a closed set-up of Panov and co-workers at strongly reduced pressure. The total amount of surface oxygen determined through multipulse experiments was in the range of the amount obtained in the vacuum set-up at 523 K (40-50 mu mol O g(catalyst)(-1)). In contrast, the step technique revealed considerably higher values, up to 110 mu mol O g(catalyst)(-1), indicating an accumulation of oxygen in the zeolite. This phenomenon might also be responsible for the observation that higher cat reaction temperatures increase the total amount of surface oxygen, which can be deposited in the zeolite. In contrast to experiments in the vacuum set-up, the temperature-programmed desorption after multipulse and step experiments shows the presence of various oxygen species differing in thermal stability. The influence of temperature on the rate of surface oxygen formation was determined from step and vacuum experiments. The results of the step experiments lead to a lower activation energy, 14 kJ mol(-1), than the experiments in the vacuum set-up (49 kJ mol(-1)), probably due to sorption and mass transfer effects. Comparing the rate of surface oxygen formation and of total N2O decomposition reveals that the former is very fast and not rate determining for the latter. Furthermore, the rate of total N2O decomposition seems to be inhibited by adsorbed N2O, detected in the transient experiments. This observation is considered in an adequate kinetic model. (c) 2007 Elsevier B.V. All rights reserved.Öğe Heavy metal removal from aqueous solution by Pseudevernia furfuracea (L.) Zopf(WILEY-V C H VERLAG GMBH, 2007) Ates, Ayten; Yildiz, Atilla; Yildiz, Nuray; Calimli, AylaThe present study was carried out in a batch system using a lichen (Pseudevernia furfuracea (L.) Zopf) for the sorption of nickel(II) and copper(II) ions from water. Particularly, the effect of pH, contact time and temperature were considered. Pseudevernia furfuracea exhibited nickel(II) and copper(II) uptake of 49.87.and 60.83 mg/g at an initial pH of 4 and 5-6 at 35 degrees C respectively. Both the Freundlich and Langmuir adsorption models were suitable for describing the biosorption of nickel(II) and copper(II) by the biosorbent. Biosorption showed pseudo first order rate kinetics for nickel and copper ions. Using the equilibrium constant values obtained at 25 and 35 T, the thermodynamics properties of the biosorption (Delta G degrees, Delta H degrees and Delta S degrees) were determined. The biosorption of nickel(II) and copper(II) onto Pseudevermajurfuracea was found to be endothermic.Öğe Influence of treatment conditions on decomposition activity of N2O over FeZSM-5 with high iron content(ROYAL SOC CHEMISTRY, 2014) Ates, AytenThe influence of treatment on formation and activity of surface oxygen over FeZSM-5 with high iron content was studied by using a transient multipulse technique combined with temperature-programmed desorption (TPD) and steady-state kinetics. All samples after various treatments were characterised by N-2 sorption, NH3-TPD, H-2-TPR, and DR-UV-vis. Multipulse experiment results showed that the reductive and inert treatments increase the amount of surface oxygen species formed from N2O. However, the oxidative treatment inhibits almost half of the oxygen formation. High temperature treatment increases not only the surface oxygen amount but also steady-state decomposition of N2O. Based on TPD and CO oxidation with surface oxygen, the active oxygen species formed from N2O are desorbed at low temperature and their amounts increase with oxidative and vacuum treatments and decrease with high temperature treatment. Vacuum treatment in a batch system increases the amount of surface oxygen and prevents transformation of active oxygen species to inactive oxygen species.Öğe Influence of V2O5 loading on the dielectric properties and AC conductivity of TiO2(Springer, 2024) Ates, Ayten; Ben Brahim, Khawla; Oueslati, Abderrazek; Gargouri, MohamedThe interaction between TiO2 and V2O5 can not only improve the physico-chemical properties of the material but also the dielectric and conductive properties of the material. For this purpose, TiO2 samples with 5, 7, and 10 wt% V2O5 were prepared by the impregnation method to investigate the dielectric properties and AC conductivity. The phase composition and morphology of the V2O5/TiO2 samples were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM)-scanning transmission electron microscope (STEM). Regardless of the vanadium content, the samples exhibit non-spherical structures and particles with size in the range of 60-200 nm. The small V2O5 peaks in XRD were detected at 7.0 and 10 wt% V2O5. In addition, the specific surface area for 5 and 7 wt% V2O5 was determined to be 9.2 m2/g, but at 10 wt% V2O5 the surface area of the sample decreases to 7.5 m2/g as the titanium dioxide pores are filled by vanadium. The DR-UV-Vis spectra of V2O5/TiO2 samples showed that the sample with 5 wt% V2O5 has isolated tetrahedrally coordinated V5+ species and increasing the V2O5 loading leads to the formation of octohedrally coordinated V5+ species in V2O5 clusters. Comparison of the Raman spectra of V2O5/TiO2 and TiO2 samples showed the formation of alpha-V2O5 on the TiO2. In addition, a detailed analysis of the Nyquist diagrams shows how sensitively the electrical properties of the materials react to changes in temperature and frequency. Jonscher's power law is used to analyze alternating current and conductivity, and it is found that the fluctuation of the exponent s adequately describes the conduction mechanism and agrees with CBH models. As the TiO2 concentration increases, the value of the activation energy generated decreases. The higher presence of Ti4+ ions due to the increase in molar volume is the cause of this increase in charge carrier mobility. The effect of the grain and grain boundary on the overall impedance is revealed by a dielectric study, which also confirms that the combination of titanium dioxide and vanadium oxide nanoparticles improves the dielectric and AC conductivity of the samples.Öğe Investigation of physicochemical and chemical properties of biochar activated with carbonate, nitrate, and borohydride(Springer Heidelberg, 2024) Ates, AytenActivation of biomass before pyrolysis with various chemicals significantly affects the surface area and porosity, chemical composition, and formation and distribution of functional groups on the surface of the biochar produced. For this purpose, raw tea waste (RTW) was mixed with potassium nitrate (KNO3), potassium sodium carbonate (NaKCO3), and sodium borohydride (NaBH4) in solid form and pyrolyzed at 500 degrees C for 1 h. The effects of the chemical activators on biomass char formation were investigated using DTA-TGA and DSC. Compared to conventional pyrolysis, carbonate, nitrate, and hydrides increase the gasification of biochar by catalyzing the decomposition of cellulose and lignin. The effect of NaBH4 on graphitization and deoxidation of carbon is higher than that of carbonates and nitrides. In addition, all prepared biochar samples were characterized by XRD, SEM, FT-IR, elemental analysis, and N-2 adsorption-desorption. While treatment of RTW with KNO3 and NaKCO3 increased the hydroxylation of the biochar, treatment with NaBH4 decreased hydroxylation by increasing dehydrogenation and dehydroxylation. Increasing boron content led to hydroxylation of the material with hydratation of NaBO2. The surface area and pore distribution results showed that nitrates and carbonates have insignificant effect on the surface area of biochar, while NaBH4 almost doubles the surface area and total pore volume of biochar by forming hydrogen.Öğe The modification of aluminium content of natural zeolites with different composition(ELSEVIER SCIENCE BV, 2019) Ates, AytenA series of natural zeolites with different compositions were modified by formation of hydrated aluminium oxide onto the zeolite structure after NaOH treatment of the natural zeolites. Natural and modified zeolites were characterized by XRD, SEM, N-2 adsorption-desorption, FTIR, zeta potential and temperature-programmed desorption of ammonia (NH3-TPD). The treatment with NaOH and then aluminium loading significantly alter zeolite characteristics depending on zeolite composition and structure. The treatment with NaOH causes significant desilication and partial dealumination of the zeolites irrespective of their compositions. The presence of quartz and feldspar phases in the zeolites increases their stability towards alkali treatment. Aluminium introduction into the zeolites treated with NaOH leads to reorganisation of zeolite structure and surface characteristics. The introduction amount of aluminium is strongly related with zeolite composition that aluminium oxide phase is detected on zeolites undergone highly desilication with NaOH treatment. Both alkali treatment and aluminium loading dramatically alter distribution of acid sites in the zeolites that while alkali treatment increases mostly strong acid sites of zeolites, aluminium loading enhances weak and medium acid sites. Enhanced aluminium content of zeolites improved its manganese adsorption capacity depending on their composition. (C) 2018 Elsevier B.V. All rights reserved.Öğe Modification of natural zeolite with NaOH for removal of manganese in drinking water(ELSEVIER SCIENCE BV, 2016) Ates, Ayten; Akgul, GokcenNatural zeolite (NZ) obtained from the Manisa-Demirci region of Turkey was modified by NaOH aqueous solutions (0.5-2.0 mol/dm(3)) and the adsorption capacity of natural and modified forms was determined for manganese removal. The characterisations of the zeolites were carried out by XRD, N-2 sorption, FTIR, NH3-TPD and SEM-EDS. Treatment of the NZ with NaOH leads to a significant decrease of its silica content by desilication and an increase of its Na content by formation of hydroxysodalite. It was seen from the NH3-TPD results that NaOH treatment alters the acidity of zeolite. While the number of weak and medium Bronsted/Lewis acid sites decreases, the number of strong acid sites increases through the intraduction of Na+ and the removal of silica. Treatment with NaOH has the effect of multiply by two the manganese adsorption capacity of the natural zeolite. The maximum manganese adsorption capacity was achieved with the zeolite treated with 1.5 M of NaOH. More than this concentration of NaOH leads not only to a decrease in adsorption capacity of natural zeolite for manganese, but also to a significant deformation of the zeolite structure. The Langmuir isotherm model fits well with the results obtained from manganese adsorption on natural zeolite, while the Freundlich isotherm model fits well with the results obtained on NaOH modified zeolites. (C) 2015 Elsevier B.V. All rights reserved.Öğe Optimization of Paracetamol and Chloramphenicol Removal by Novel Activated Carbon Derived from Sawdust Using Response Surface Methodology(MDPI, 2023) Romdhani, Mohamed; Attia, Afef; Charcosset, Catherine; Mahouche-Chergui, Samia; Ates, Ayten; Duplay, Joelle; Amar, Raja BenParacetamol (PCT) and chloramphenicol (CPL) can have unfavorable impacts on human health, as well as on natural ecosystems. These substances contribute to the aquatic environment's contamination and disturb the performance of municipal wastewater treatment systems, causing ecosystem disruption and microbial resistance. In this study, activated carbon produced from sawdust (ACs) was synthesized utilizing the chemical activation process for the removal of both PCT and CPL compounds from an aqueous solution. ACs has a primarily microporous structure with a significant specific surface area of 303-1298 m(2)/g, total pore volume of 0.462 cm(3)/g and bimodal distribution of pores of 0.73-1.7 nm. The removal efficiencies for PCT and CPL with the low-cost activated carbon, determined at the optimum dose (750 mg/L for PCT and 450 mg/L for CPL), were significantly high at 85% and 98%, respectively. The adsorption kinetics for both pharmaceuticals exhibited a quick initial decline. For PCT and CPL adsorption, the equilibrium was attained after just 20 and 90 min, respectively. The Langmuir isotherm model and the pseudo-second-order kinetics model offered the best fits for the adsorption of both compounds. Additionally, the central composite design (CCD) and Box-Behnken design (BBD) were used to optimize the experimental adsorption conditions using a response surface methodology (RSM). On the basis of the findings, it is evident that activated carbon made from sawdust may be used as a new, effective alternative adsorbent for removing PCT and CPL in aqueous environments.
