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Öğe ADSORPTION AND DESORPTION KINETICS BEHAVIOUR OF METHYLENE BLUE ONTO ACTIVATED CARBON(Oficyna Wydawnicza Politechniki Wroclawskiej, 2012) Sarici-Ozdemir, CigdemIn the present work investigations on a potential use of activated carbon for the removal of Methylene Blue (MB) from wastewater are presented. Adsorption kinetics of methylene blue has been studied using reaction-based and diffusion-based models. Three kinetic models, namely, pseudo-first-order, pseudo-second-order and the Elovich are analyzed at the temperature of 298 K for the reaction-based model. The kinetic studies showed that the data were well described by the pseudo-second-order kinetic model. Intraparticle diffusion, external-film diffusion, and internal-pore diffusion models characterizing MB were obtained. The results suggested that the activated carbon has a high potential to be used as an effective adsorbent for methylene blue adsorption. Pseudo first-order, pseudo second-order and the Elovich models were employed to describe the desorption mechanism. The experimental results showed that the pseudo second-order equation is the best model. About 99% of activated carbon has been regenerated by desorption.Öğe Degradation Products of Rhyolitic Rocks, Adsorption Applications, Isotherm Studies(Taylor & Francis Inc, 2024) Firat, Tulay; Sarici-Ozdemir, CigdemHeavy metals and their toxicity are a major global concern. They are one of the major environmental problems causing serious problems for living beings. In this study, the adsorption properties of a clay sample located in nature are improved by treating with different materials, and then adsorption properties are examined. It is observed that clay sample can be used in many adsorption applications, including the adsorption of heavy metals such as copper. The clay mineral used in the study was obtained from a rhyolite type rock. Rhyolite rocks, one of the degradation products of volcanic rocks, are the volcanic counterparts of granite. In this study, rhyolite rock was crushed with suitable crushers and grinders, then sieved under 200 mesh with molecular sieve and clay minerals were obtained. The clay samples (K1,K2. K8) were synthesized by subjecting clay with acid and base. Adsorption properties of clay are due to wide surface area, surface functional groups and microporosity. Adsorption of methylene blue and iodine, adsorption from aqueous solutions of copper are done with clay samples and results were compared with samples of clay have not undergone any pre-treatment. In the study, the highest adsorption capacity was determined by applying the Freundlich isotherm. In the K6 sample treated with a base, the highest adsorption capacity was calculated as 26.98 Lg-1. In contrast, the Langmuir isotherm results were calculated in the range of 10.56 to 11.86 Lg-1. This indicates that the adsorption takes place on a heterogeneous surface. The structure and surface properties of clay were examined.Öğe Equilibrium, kinetic and thermodynamic adsorptions of the environmental pollutant tannic acid onto activated carbon(Elsevier Science Bv, 2010) Sarici-Ozdemir, Cigdem; Onal, YunusPolymeric waste, which is the main waste from textural industry in Turkey, was used as the raw material for the preparation of activated carbon by chemical activation with KOH. The pore properties, such as BET surface area, pore volume, pore-size distribution, and pore diameter, of the activated carbon were characterized by the t-plot based on the N-2-adsorption isotherm. The BET surface area of activated carbon (SK) was determined as 2390 m(2)/g. Activated carbon has been used for the removal of tannic acid from aqueous solutions. Adsorption experiments were carried out as a function of initial tannic acid concentration, contact time, and pH. Adsorption data were modeled using the Langmuir and Freundlich adsorption isotherms. The kinetic studies showed that the adsorption followed a pseudo second-order reaction. The intraparticle diffusion rate constant, external mass transfer coefficient, film and pore diffusion coefficients at various temperatures were evaluated. The thermodynamic parameters, such as Delta G(0), Delta S-0, and Delta H-0, were calculated. The thermodynamics of tannic acid-SK system indicates endothermic process. (c) 2009 Elsevier B.V. All rights reserved.Öğe Error Anlaysis Studies of Dye Adsorption onto Activated Carbon from Aqueous Solutions(Taylor & Francis Inc, 2014) Sarici-Ozdemir, Cigdem; Onal, YunusAdsorption of tartrazine and methylene blue from aqueous solution onto activated carbon has been investigated. Experimental datas obtained from dye adsorption have been studied by five two-parameter (Langmuir, Freundlich, Dubinin-Radushkevich, Temkin, and Frumkin), five three-parameter (Redlich-Peterson, Sips, Toth, Radke-Prausnitz, Koble-Corrigan) isotherm models. In this study, eight nonlinear error functions (sum squares errors, hybrid fractional error function, Marquardt's percent standard deviation, average relative error, sum of absolute error, the coefficient of determination, nonlinear chi-square test, and standard deviation of relative errors) were examined for isotherm equations. In order to clarify the adsorption kinetics fit of pseudo-first order and pseudo-second order kinetic models were used. The best fitting isotherm model was the Radke-Prausnitz and kinetics model was pseudo-second order for two dyes. Adsorption experiment showed that the maximum capacity of activated carbon's for methylene blue and tartrazine were 28.571 and 18.182mg.g(-1), respectively.Öğe Examination of the adsorption for methylene blue using different adsorbents(Desalination Publ, 2017) Sarici-Ozdemir, CigdemThis study was conducted on methylene blue adsorption using adsorbents obtained in different ways. These adsorbents were divided into four groups among its members. Activated carbon obtained after chemical activation, clay, industrial waste and agricultural waste constitutes this group. Adsorbents were characterized by X-ray diffractometer, scanning electron microscopy and Fourier-transform infrared spectroscopy. The adsorption of methylene blue onto adsorbents was investigated by calculating the parameters of contact time, the concentration of methylene blue and adsorbent dosage. Experimental data obtained from dye adsorption were studied by five two-parameter (Langmuir, Freundlich, Dubinin-Radushkevich, Temkin and Frumkin), five three-parameter (Redlich-Peterson, Sips, Toth, Radke-Prausnitz, Koble-Corrigan) isotherm models. The Langmuir and Freundlich model denotes a better value of correlation coefficient than other models. The amount of methylene blue adsorption at equilibrium by the adsorbents showed the following order; clay > activated carbon > fly ash > pine cone. Maximum adsorption capacity for methylene blue was calculated 250 mg g(-1) at clay.Öğe Experimental and modeling studies of methylene blue adsorption onto particles of peanut shell(Taylor & Francis Inc, 2016) Kilic, Fatih; Sarici-Ozdemir, CigdemIn this study, adsorption of methylene blue from aqueous solution onto peanut shell has been investigated. Experimental data obtained from dye adsorption have been studied by five two-parameter (Langmuir, Freundlich, Dubinin-Radushkevich, Temkin, and Frumkin) and five three-parameter (Redlich-Peterson, Sips, Toth, Radke-Prausnitz, and Koble-Corrigan) isotherm models. Eight nonlinear error functions (sum squares errors, hybrid fractional error function, Marquardt's percent standard deviation, average relative error, sum of absolute error, the coefficient of determination, nonlinear chi-square test, and standard deviation of relative errors) were examined for isotherm equations. In order to explain the adsorption kinetics fit of pseudo-first-order, pseudo-second-order, Elovich, and intraparticle kinetic models were used. The best fitting isotherm model was the Radke-Prausnitz and kinetics model was pseudo-second-order. Adsorption experiment showed that the maximum capacity of agricultural waste for methylene blue was 67.57 L.g(-1) at 25 degrees C.Öğe INVESTIGATING REMOVAL OF TRIMETHYLXANTHINE BY ACTIVATED CARBON PREPARED FROM PET WASTE(Parlar Scientific Publications (P S P), 2012) Sarici-Ozdemir, Cigdem; Onal, YunusActivated carbon (BK) has been prepared from polymeric wastes by chemical activation with KOH. Adsorption of trimethylxanthine onto BK was investigated with variations of pH, contact time, trimethylxanthine concentration, and temperature. The results were analyzed by the Langmuir and Freundlich equations. Adsorption of trimethylxanthine (caffeine) onto BK follows the Langmuir isotherm model. The kinetics of trimethylxanthine adsorption has been discussed using three kinetic models, i. e., the pseudo first-order, the pseudo second-order, and the intraparticle diffusion models. The kinetic studies showed that the adsorption followed a pseudo second-order reaction. The intraparticle diffusion rate constant, the external mass transfer coefficient, film and pore diffusion coefficients at various temperatures were evaluated. The thermodynamic parameters, such as Delta G degrees, Delta S degrees, and Delta H degrees, have been calculated. The thermodynamics of the trimethylxanthine -BK system indicated an endothermic process.Öğe Kinetics behavior of methylene blue onto agricultural waste(Taylor & Francis Inc, 2018) Sarici-Ozdemir, Cigdem; Kilic, FatihIn the present work, investigations on a potential use of agricultural waste for the removal of methylene blue (MB) from wastewater are presented. Adsorption kinetics of MB has been studied using reaction-based and diffusion-based models. Three kinetic models, namely pseudo-first-order, pseudo-second-order, and the Elovich are analyzed at the temperature of 298 K for the reaction-based model. The kinetic studies showed that the data were well described by the pseudo-second-order kinetic model. Intraparticle diffusion, external-film diffusion, and internal-pore diffusion models characterizing MB were obtained. The results suggested that the agricultural waste has a high potential to be used as an effective adsorbent for MB adsorption. Pseudo-first-order, pseudo-second-order, and the Elovich models were employed to describe the desorption mechanism. The experimental results showed that the pseudo-second-order equation is the best model.Öğe Removal of Methylene Blue by Activated Carbon Prepared from Waste in a Fixed-Bed Column(Taylor & Francis Inc, 2014) Sarici-Ozdemir, CigdemIn this study, the ability of activated carbon prepared from waste to adsorb methylene blue from aqueous solution was investigated in a fixed-bed column. The effect of flow rate and inlet methylene blue concentration on the adsorption characteristics of activated carbon was investigated at 25 degrees C. Freundlich and Langmuir adsorption models have been used to represent the column equilibrium data. The Langmuir constants of Q(o) and b were determined as 6.38mg center dot g(-1) and 0.34L center dot mg(-1), respectively. The results showed that the equilibrium data fitted Langmuir isotherm within the concentration range studied. Four kinetic models, Adams-Bohart, Wolborska, Thomas, and Yoon-Nelson, were applied to experimental data to predict the break-through curves and determine the characteristic parameters of the column useful for process design. Results also indicate that the adsorption process can only deal with lower flow rates and lower concentrations of methylene blue solution if a high percentage of removal is required for extended periods. All models were found suitable for methylene blue adsorption onto activated carbon.Öğe Statistical analysis of equilibrium and kinetic data for ascorbic acid removal from aqueous solution by activated carbon(Desalination Publ, 2013) Sarici-Ozdemir, Cigdem; Onal, YunusThe adsorption of ascorbic acid from aqueous solution onto activated carbon was investigated at different concentrations and temperatures. Equilibrium data were analysed using Langmuir, Freundlich, Dubinin-Radushkevich (D-R), Temkin and Frumkin isotherms. All of the isotherm parameters were calculated and showed that they were well explained by the Langmuir, Temkin and Frumkin isotherms models, as compared with the D-R and Freundlich isotherms. Maximum adsorption capacity was determined to be 520.80mgg(-1) according to the Langmuir isotherm. The mean free energy values (E) according to the D-R isotherm were estimated to be 12.50kJmol(-1). In order to clarify the adsorption kinetics, the fits of pseudo-first-order kinetics second-order kinetics, and Elovich models were compared. It was determined that the ascorbic acid adsorption process followed pseudo-second-order rate kinetics. Kinetic and equilibrium data were evaluated according to standard deviation and correlation coefficients. The external mass transfer coefficient, as well as the film and pore diffusion coefficients were also evaluated at various temperatures.Öğe STUDIES ON REMOVAL OF NAPROXEN SODIUM BY ADSORPTION ONTO ACF IN BATCH AND COLUMN(Parlar Scientific Publications (P S P), 2012) Sarici-Ozdemir, Cigdem; Onal, Yunus; Erdogan, Selim; Akmil-Basar, CananIn this study, activated carbon fibers were prepared from textile waste by chemical activation with ZnCl2 (and coded IPZN1, IPZN2, and IPZN3). After preparation they were characterized by analyses using the BET surface area, FT-IR, and XRD methods. The ability of IPZN1, to remove naproxen sodium from effluent solutions by adsorption was studied. Results were analyzed by the Langmuir, Freundlich, Dubinin-Radushkevich (D-R), Temkin, Frumkin, Halsey and Henderson equations using linearized correlation coefficients at 298 K. The value of Q(0) was determined as 294.11 mg.g(-1) and the Delta G value of -21.46 kJ.mol(-1) for adsorption of naproxen sodium. The fixed-bed adsorption system was used for study of the adsorption of naproxen sodium onto IPZN1. Experiments were conducted to study the effect of flow rate of naproxen sodium. Decreasing the flow rate was found to enhance capacity. The breakthrough data obtained for naproxen sodium was adequately described by the Thomas and Yoon-Nelson adsorption models. This study revealed that ACF is suitable for use as an effective adsorbent for the adsorption of naproxen sodium.Öğe Study to investigate the importance of mass transfer of naproxen sodium onto activated carbon(Elsevier Science Sa, 2010) Sarici-Ozdemir, Cigdem; Onal, YunusIn the present study the adsorption of naproxen sodium onto activated carbons (BK4 obtained from white polymeric waste and SK4 obtained from black polymeric waste) was investigated by calculating the parameters of pH contact time the concentration of naproxen sodium and the temperature The adsorption data of naproxen sodium onto activated carbon follows the Langmuir isotherm model and its kinetic processes were described by various kinetic adsorption models It was determined that the pseudo-second-order model was the best choice among all the available kinetic models to describe the adsorption behaviour of naproxen sodium onto activated carbon During the present study the intra-particle diffusion rate constant the external mass transfer coefficient and the film and pore diffusion coefficient were evaluated at various temperatures In addition the thermodynamic parameters of the adsorption of naproxen sodium onto activated carbon were also calculated Crown Copyright (C) 2010 Published by Elsevier B V All rights reservedÖğe Study to observe the applicability of the adsorption isotherms used for the adsorption of medicine organics onto activated carbon(Taylor & Francis Inc, 2018) Sarici-Ozdemir, Cigdem; Onal, YunusIn the present study, the activated carbon was prepared by chemically activating polymer waste under the influence of potassium hydroxide (KOH). The pore properties including the Brunauer-Emmett-Teller (BET) surface area, the volume of the pore, its size distribution, and average diameter were also characterized herein. The present study also evaluated the ability of the activated carbon to remove naproxen sodium, tannic acid, and caffeine from aqueous solutions through a process of adsorption. The equilibrium isotherms employed for the adsorption of drug organics onto the activated carbon were measured experimentally. The obtained results were analyzed by employing the Redlich-Peterson, Dubinin-Redushkevich, Temkin, Frumkin, Halsey, and Henderson equations by using a linearized correlation coefficient and statistically at varied temperatures. The models and the isotherm constants were evaluated based on the changes in the temperature. Among all, the Redlich-Peterson equation was determined to best represent the equilibrium data for the adsorption of naproxen sodium, and caffeine onto the activated carbon.Öğe Synthesis of new activated carbons produced from polymer waste(Taylor & Francis Inc, 2018) Sarici-Ozdemir, Cigdem; Onal, YunusIn this study activated carbons were prepared from polymer waste, which is side product and waste in textile industry; by chemical activation with KOH. The influence of chemical ratio onto pore structure was investigated. Activation temperature was selected as 800 degrees C. The impregnated sample was raised to the activation temperature under N-2 (100mL. min(-1)) atmosphere with 10 degrees C. min(-1) heating rate and hold at this temperature for 1h. Determined BET surface area were in the range of 817-1889m(2)g(-1). Impregnation ratio; 5:1 was found to be the optimal condition for producing high surface area carbons with KOH activation. Activated carbon samples and raw material were characterized by Boehm titration, XRD, FT-IR, DTA and TGA. Adsorption capacity for selected model compound, such as naproxen sodium, caffeine and tannic acid, has been investigated.
