Personal Research Database

Full Text: 2009\Sep Sci Tec44, 1638.pdf

Abstract: The treated almond peels (TAP) have been employed as adsorbents for the removal of Brilliant green dye from waste water. The nature of possible adsorbent and dye interaction was examined by the FTIR and SEM technique. The adsorption of BG was found to be maximum (93%) at pH 8. The extent of removal of BG was found to be dependent on the adsorbent dose, the temperatures, and the times. The equilibrium data for adsorption was best represented by the Langmuir isotherm. Thermodynamic parameters (ΔH and ΔG) suggest endothermic and spontaneous process. Kinetic studies show better applicability of second-order kinetic model. The practical utility of TAP was demonstrated by removing BG from pure solution and industrial effluent system by column process. It was found that the removal effficiency of TAP was better by pure solution. The breakthrough capacities of pure solution and industrial effluent systems on TAP are found to be 30 and 17 mg, g, respectively.

Keywords: Activated Carbon, Adsorbent, Adsorbent Dose, Adsorbents, Adsorption, Adsorption Characteristics, Almond, Aqueous-Solution, Biosorption, Breakthrough, Brilliant Green, Capacity, Characterization, Column, Data, Desorption, Desorption, Dye, Dye Adsorption, Effluent, Endothermic, Equilibrium, FTIR, Industrial Effluent, Interaction, Isotherm, Kinetic, Kinetic Model, Kinetic Studies, Kinetics, Langmuir, Langmuir Isotherm, Model, Palm-Fruit Bunch, pH, Recovery, Removal, Second Order, Second-Order, SEM, Solution, Sorption, Systems, Thermodynamic, Thermodynamic Parameters, Utility, Waste, Waste Water, Wastewater, Water, Wheat-Straw

? Gercel, O. and Gercel, H.F. (2009), Removal of acid dyes from aqueous solutions using chemically activated carbon. Separation Science and Technology, 44 (9), 2078-2095.

Full Text: 2009\Sep Sci Tec44, 2078.pdf

Abstract: Textile dyes (Acid Yellow 17 and Acid Orange 7) were removed from its aqueous solution in batch and continuous packed bed adsorption systems by using thermally activated Euphorbia macroclada carbon with respect to contact time, initial dye concentration, and temperature. The activated carbon was prepared using a cheap plant-based material called Euphorbia macroclada, which was chemically modified with K₂CO₃. Lagergren-first-order and second-order kinetic models were used to fit the experimental data. Equilibrium isotherms were analyzed by Langmuir and Freundlich isotherms. Equilibrium data fitted well the Langmuir model in the studied temperature (25-55ºC) ranges. The maximum adsorption capacity of AY17 and AO7 onto activated carbon was found to be 161.29 and 455 mgg^-1, respectively by Langmuir isotherm at 55°C. Breakthrough curves for column adsorption have also been studied. The desorption of dyes has been experimentally investigated using NaOH solution of pH 11.

Keywords: Acid Dye, Activated Carbon, Activation, Adsorbents, Adsorption, Adsorption, Adsorption Capacity, Aqueous Solution, Batch, Biomass, Capacity, Carbon, Column, Concentration, Continuous Packed Bed, Data, Desorption, Dye, Dyes, Equilibrium, Equilibrium Isotherms, Experimental, Freundlich, Isotherm, Isotherms, K₂CO₃, Kinetic, Kinetic Models, Kraft Lignin, Langmuir, Langmuir And Freundlich Isotherms, Langmuir Isotherm, Langmuir Model, Model, Models, Modified, Naoh, Packed Bed, Peat, pH, Physical Activation, Removal, Second Order, Second-Order, Shell, Solution, Systems, Temperature, Textile Dyes

? Anirudhan, T.S., Rijith, S. and Divya, L. (2009), Preparation and application of a novel functionalized coconut coir pith as a recyclable adsorbent for phosphate removal. Separation Science and Technology, 44 (12), 2774-2796.

Full Text: 2009\Sep Sci Tec44, 2774.pdf

Abstract: This study was to develop a new adsorbent, Iron(III) complex of an amino-functionalized polyacrylamide-grafted coconut coir pith (CP), a lignocellulosic residue, for the removal of phosphate from water and wastewater. The kinetics of adsorption follows a pseudo-second-order model. The equilibrium sorption capacity of 96.31 mg/g was determined at 30°C from the Langmuir isotherm equation. Complete removal of 16.4 mg/L phosphate in 1 L of fertilizer industry wastewater was achieved by 1.5 g/L AM-Fe-PGCP at pH 6.0. The acid treatment (0.1M HCl) and re-introduction of Fe³⁺ lead to a reactivation of the spent adsorbent and can be reused through many cycles of water treatment and regeneration without any loss in the adsorption capacity.

Keywords: Acid Treatment, Acid-Treatment, Adsorbent, Adsorption, Adsorption Capacity, Adsorption Isotherm, Aqueous-Solutions, Capacity, Carbon, Chitosan, Coir Pith, Equilibrium, Fertilizer, Graft Copolymerization, Heavy-Metal Ions, Isotherm, Kinetics, Kinetics of Adsorption, Langmuir, Langmuir Isotherm, Lead, Model, pH, Phosphate, Phosphorus, Pith, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Regeneration, Removal, Removal Of Phosphate, Solids, Sorption, Sorption Capacity, Treatment, Wastewater, Wastewaters, Water, Water Treatment

? Xing, Y. and Deng, D.H. (2009), Enhanced adsorption of malachite green by EDTAD-modified sugarcane bagasse. Separation Science and Technology, 44 (9), 2117-2131.

Full Text: 2009\Sep Sci Tec44, 2117.pdf

Abstract: Ethylenediaminetetraacetic dianhydride (EDTAD) modified sugarcane bagasse (SB) was prepared and characterized by Fourier transform infrared spectroscopy (FTIR). Due to the presence of a large number of carboxyl groups, the adsorption capacity of the EDTAD modified SB (EDTAD-SB) for malachite green (MG) showed a significant increase compared with SB. Increase in ion strength of solution-induced decline of MG sorption. The maximum adsorption capacities were 157.2 mg g^-1 for MG, according to the Langmuir equation. Kinetic studies showed better correlation coefficients for a pseudo-second-order kinetic model, confirming that the sorption rate was controlled by a chemisorption process.

Keywords: Adsorbent, Adsorption, Adsorption Capacities, Adsorption Capacity, Aqueous-Solutions, Bagasse, Capacity, Chemisorption, Correlation, Dye, Equilibrium, Ethylenediaminetetraacetic Dianhydride, Fiber, FTIR, Infrared Spectroscopy, Ion Strength, Ions, Kinetic, Kinetic Model, Kinetic Studies, Kinetics, Langmuir, Langmuir Equation, Malachite Green, Mg, Model, Modified, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Removal, Sorption, Spectroscopy, Strength, Sugarcane, Sugarcane Bagasse

? Baldez, E.E., Robaina, N.F. and Cassella, R.J. (2009), Study of rhodamine b retention by polyurethane foam from aqueous medium in presence of sodium dodecylsulfate. Separation Science and Technology, 44 (13), 3128-3149.

Full Text: 2009\Sep Sci Tec44, 3128.pdf

Abstract: This work reports a study about the adsorption of Rhodamine B (RB) by unloaded polyether type polyurethane foam (PUF) in a medium containing sodium dodecylsulfate (SDS). The adsorption process was based on the formation of an ionic-pair between RB and SDS, which presented high affinity by PUF. Adsorption was characterized in relation to equilibrium, kinetic, and thermodynamic aspects and the results obtained showed that the ratio between the SDS and RB concentrations played an important role on the adsorption efficiency. A maximum adsorption capacity of 6.85×10^-6 molRBg^-1 was observed at established experimental conditions. The adsorption process was spontaneous (negative G) and presented an endothermic characteristic (positive H). Also, its rate was regulated by an intraparticle diffusion process. Sequential extraction experiments were carried out by changing PUF plugs in 30 and 60min time intervals, resulting in removal rates higher than 95%.

Keywords: Adsorption, Adsorption Capacity, Basic-Dyes, Capacity, Cationic Dye, Cationic Dyes, Diffusion, Efficiency, Endothermic, Equilibrium, Experimental, Experiments, Extraction, Foam, Intervals, Intraparticle Diffusion, Kinetic, Malachite-Green, Metal-Ions, Methylene-Blue, Polyurethane, Polyurethane Foam, Rates, Reactive Dyes, Removal, Rhodamine B, Role, Sds, Sodium, Solid-Phase Extraction, Sorption, Thermodynamic, Water, Work

? Bhatnagar, A., Minocha, A.K., Kumar, E., Sillanpää, M. and Jeon, B.H. (2009), Removal of phenolic pollutants from water utilizing Mangifera indica (Mango) seed waste and cement fixation. Separation Science and Technology, 44 (13), 3150-3169.

Full Text: 2009\Sep Sci Tec44, 3150.pdf

Abstract: A process for the removal of two chlorophenols (2-chlorophenol and 2,4-dichlorophenol) from water using surface modified mango seed waste by adsorption process followed by cement fixation of the phenols-laden adsorbent is investigated. The two main objectives of this study were to develop efficient adsorbent utilizing mango seed waste by physiochemical activation and to an environmentally-friendly disposal of phenols-laden adsorbent into cement by a fixation process. The results of the present study reveal that the modified mango seed adsorbent showed an efficient adsorption potential for chlorophenols removal from water. The maximum adsorption potential of modified mango seed adsorbent for 2-chlorophenol and 2,4-dichlorophenol was 40.6 and 72.3mgg^-1, respectively at 25ºC. Adsorption kinetic data of chlorophenols adsorption on mango seed adsorbent could be described more favorably by a pseudo-second-order kinetic model. After the adsorption studies, the phenol-laden adsorbent was immobilized in cement for its ultimate disposal. Leachates from the fixed phenols-laden adsorbent exhibit phenols concentrations lower than the drinking water standards. Results from this study suggest the potential utility of agricultural wastes as one of the most promising activated carbon precursors for phenols removal from water and wastewater and the safe disposal of phenol-laden adsorbent into cement by fixation process.

Keywords: 2,4-Dichlorophenol, 2-Chlorophenol, Activated Carbon, Activation, Adsorbent, Adsorption, Adsorption Kinetic, Adsorption Study, Agricultural, Agricultural Waste, Agricultural Wastes, Aqueous-Solutions, Carbon, Cement, Cement Fixation, Chlorinated Phenols, Chlorophenols, Chlorophenols, Data, Degradation, Disposal, Drinking Water, Drinking Water Standards, Environmentally Friendly, Equilibrium, Immobilized, Kinetic, Kinetic Model, Mango Seed Waste, Model, Modified, Phenols, Potential, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Removal, Sorption, Standards, Substituted Phenols, Surface, Surface Modification, Utility, Waste, Wastewater, Water, Water Standards

? Ayranci, E. and Duman, O. (2009), In-Situ UV-Visible Spectroscopic Study on the Adsorption of some Dyes onto Activated Carbon Cloth. Separation Science and Technology, 44 (15), 3735-3752.

Full Text: 2009\Sep Sci Tec44, 3735.pdf

Abstract: Adsorptive removal of the dyes C.I. Basic Blue 9, C.I. Basic Red 2, and C.I. Acid Blue 74 from aqueous solution onto the activated carbon cloth (ACC) has been investigated. The removal of each dye has been followed by in-situ UV-visible spectroscopic method using the so-called scanning kinetics technique. Kinetic data obtained in this way were tested according to pseudo-first order, pseudo-second order, Elovich, and intraparticle diffusion models. Pseudo-second order model was found to be the best in representing the experimental kinetic data. Adsorption isotherms at 30ºC were derived for each dye. Isotherm data were found to fit best to Freundlich isotherm model among the three isotherm models tested, Langmuir, Freundlich, and Redlich-Peterson. High specific surface area of the ACC allowed almost complete removal of each dye under the experimental conditions applied. Adsorption capacity of the ACC for the three dyes was correlated with the dimensions of dye molecules and pore sizes of the ACC.

Keywords: Acid, Activated Carbon, Activated Carbon Cloth, Adsorption, Adsorption Capacity, Adsorption Isotherms, Aqueous Solution, Aqueous-Solutions, Basic Blue 9, Capacity, Carbon, Data, Diffusion, Dye, Dyes, Electrosorption, Elovich, Equilibrium, Experimental, Felt Electrodes, Freundlich, Freundlich Isotherm, Freundlich Isotherm Model, In Situ, In-Situ UV Spectroscopy, Intraparticle Diffusion, Isotherm, Isotherm Model, Isotherms, Kinetic, Kinetics, Langmuir, Methylene-Blue, Model, Models, Pseudo First Order, Pseudo Second Order, Pseudo-First Order, Pseudo-First-Order, Pseudo-Second Order, Pseudo-Second Order Model, Pseudo-Second-Order, Redlich-Peterson, Removal, Solution, Sorption, Specific Surface, Specific Surface Area, Surface, Surface Area, Waste-Water Purification

? Monash, P. and Pugazhenthi, G. (2010), Removal of crystal violet dye from aqueous solution using calcined and uncalcined mixed clay adsorbents. Separation Science and Technology, 45 (1), 94-104.

Full Text: 2010\Sep Sci Tec45, 94.pdf

Abstract: In this work, calcined and uncalcined mixed clays containing kaolin, ball clay, feldspar, pyrophyllite, and quartz are examined as a potential adsorbent for the removal of crystal violet dye from aqueous solution. These clays are characterized by nitrogen adsorption/desorption isotherms, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and thermo gravimetric analysis (TGA). The kinetics and thermodynamic parameters as well as the effects of the pH, the temperature, and the adsorbent dosage have also been investigated. The experimental results indicate that the Langmuir model expresses the adsorption isotherm better than the Freundlich model. The obtained result showed a tremendous increase in the crystal violet adsorption capacity (1.9×10^-3 mol g^-1) after calcination, which is one order greater than that of the uncalcined mixed clay. The mechanism of the adsorption process is elucidated on the basis of experimental data. The percentage removal of crystal violet dye increases with increasing the pH, the temperature, and the adsorbent dosage. The investigation of kinetic studies indicates that the adsorption of crystal violet on calcined and uncalcined mixed clays could be described by the pseudo-second-order model. The negative G0 values obtained from the thermodynamic investigation confirm that the adsorption is spontaneous in nature. The adsorption results suggest that the calcined and uncalcined mixed clays can also be used as low cost alternatives to the expensive activated carbon for the removal of dyes from aqueous solution.

Keywords: Acid Dye, Activated Carbon, Adsorbent, Adsorbent Dosage, Adsorption, Adsorption, Adsorption Capacity, Adsorption Isotherm, Adsorption, Desorption, Alternatives, Analysis, Aqueous Solution, Basic Dye, Calcination, Calcined, Capacity, Carbon, Clay, Clays, Cost, Crystal Violet, Data, Dye, Dyes, Equilibrium, Experimental, Freundlich, Freundlich Model, FT-IR, FTIR, Investigation, Isotherm, Isotherms, Kaolin, Kinetic, Kinetic Studies, Kinetics, Langmuir, Langmuir Model, Low Cost, Mechanism, Methylene-Blue, Model, Nitrogen, Organic-Dyes, Palygorskite, pH, Potential, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Pyrophyllite, Quartz, Removal, Removal Of Dyes, Solution, Sorption, Spectroscopy, Temperature, TGA, Thermodynamic, Thermodynamic Parameters, Water, Work, X-Ray, X-Ray Diffraction, XRD

? Yüksel, S. and Yürüm, Y. (2010), Removal of boron from aqueous solutions by adsorption using fly ash, zeolite, and demineralized lignite. Separation Science and Technology, 45 (1), 105-115.

Full Text: 2010\Sep Sci Tec45, 105.pdf

Abstract: In the present study for the purpose of removal of boron from water by adsorption using adsorbents like fly ash, natural zeolite, and demineralized lignite was investigated. Boron in water was removed with fly ash, zeolite, and demineralized lignite with different capacities. Ninety-four percent boron was removed using fly ash. Batch experiments were conducted to test the removal capacity, to obtain adsorption isotherms, thermodynamic and kinetic parameters. Boron removal by all adsorbents was affected by pH of solution, maximum adsorption was achieved at pH 10. Adsorption of boron on fly ash was investigated by the Langmuir, Freundlich, and the Dubinin-Radushkevich models. Standard entropy and enthalpy changes of adsorption of boron on fly ash were, S0=-0.69kJ/mol K and H0=-215.34kJ/mol, respectively. The negative value of S0 indicated decreased randomness at the solid/solution interface during the adsorption boron on the fly ash sample. Negative values of H0 showed the exothermic nature of the process. The negative values of G0 implied that the adsorption of boron on fly ash samples was spontaneous. Adsorption of boron on fly ash occurred with a pseudo-second order kinetic model, and intraparticle diffusion of boron species had also some effect in adsorption kinetics.

Keywords: Activated Alumina, Adsorbents, Adsorption, Adsorption Isotherms, Adsorption Kinetics, Boric-Acid, Boron, Boron Removal, Capacity, Changes, Coal, Diffusion, Enthalpy, Entropy, Exothermic, Experiments, Fly Ash, Freundlich, Hybrid Process, Interface, Intraparticle Diffusion, Ion-Exchange-Resin, Isotherms, Kinetic, Kinetic Model, Kinetic Parameters, Kinetics, Langmuir, Lignite, Mineral Matrix, Model, Models, Natural, Natural Zeolite, Oil-Shale, pH, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second-Order, Purpose, Randomness, Removal, Reverse-Osmosis, Solution, Sorption-Elution, Species, Thermodynamic, Turkey, Value, Waste-Water, Water, Zeolite

? Royer, B., Cardoso, N.F., Lima, E.C., Macedo, T.R. and Airoldi, C. (2010), Sodic and acidic crystalline lamellar magadiite adsorbents for the removal of methylene blue from aqueous solutions: Kinetic and equilibrium studies. Separation Science and Technology, 45 (1), 129-141.

Full Text: 2010\Sep Sci Tec45, 129.pdf

Abstract: The present study reports the feasibility of two synthetic crystalline lamellar nano-silicates, sodic magadiite (Na-mag) and its converted acidic form (H-mag), as alternative adsorbents for the removal of the dye methylene blue (MB) from aqueous solutions. The ability of these adsorbents for removing the dye was explored through the batch adsorption procedure. Effects such as the pH and the adsorbent dosage on the adsorption capacities were explored. Four kinetic models were applied, the adsorption being best fitted to a fractionary-order kinetic model. The kinetic data were also adjusted to an intra-particle diffusion model to give two linear regions, indicating that the kinetics of adsorption follows multiple sorption rates. The equilibrium data were fitted to Langmuir, Freundlich, Sips, and Redlich-Peterson isotherm models. The maxima adsorption capacities for MB of Na-mag and H-mag were 331 and 173mg g^-1, respectively.

Keywords: Adsorbent, Adsorbent Dosage, Adsorbents, Adsorption, Adsorption, Adsorption Capacities, Alternative, Anionic Dyes, Aqueous Solutions, Azo Dyes, Batch, Batch Adsorption, Biosorbent, Data, Diffusion, Diffusion Model, Dye, Equilibrium, Feasibility, Freundlich, Intra-Particle Diffusion, Intraparticle Diffusion, Intraparticle Diffusion Model, Isotherm, Kinetic, Kinetic Model, Kinetic Models, Kinetics, Kinetics of Adsorption, Langmuir, Magadiite, Mb, Methylene Blue, Model, Models, Multiple Sorption, Nanomaterial, Parameters, Pecan Nutshell, pH, Phyllosilicate, Procedure, Rates, Reactive Dyes, Redlich-Peterson, Removal, Silicic-Acid, Solutions, Sorption, Thin Chitosan Membranes, Yellow Passion-Fruit

? Çalişkan, E. and Göktürk, S. (2010), Adsorption characteristics of sulfamethoxazole and metronidazole on activated carbon. Separation Science and Technology, 45 (2), 244-255.

Full Text: 2010\Sep Sci Tec45, 244.pdf

Abstract: In this work, the removal of two pharmaceuticals i.e., an antibiotic drug, sulfamethoxazole and an antiparasitary drug, metronidazole onto activated carbon from aqueous solutions were studied. Batch adsorption studies were carried out at different pH, adsorbent concentrations, and temperatures. Adsorption isotherms have been modeled by Freundlich, Langmuir, and Dubinin-Raduskevitch (D-R) equations. The adsorption of these drugs was better represented by the Langmuir equation. The effect of the solution pH on the adsorbed amount of SM and MN was studied by varying the initial pH under constant process parameters at equilibrium conditions. The increase in pH of the solutions caused to decrease adsorption of SM and MN on AC. The kinetics of adsorption in view of three kinetic models, i.e., the first-order Lagergren model, the pseudo-second-order model, and the intraparticle diffusion model was discussed. The pseudo-second-order kinetic model describes the adsorption of both sulfamethoxazole and metronidazole on activated carbon. Rate constants for adsorption and desorption, and surface coverage have been evaluated with the help of another approach of the kinetic scheme. The effect of temperature was also studied at the range between 293 and 313 K. Thermodynamic parameters were calculated. The negative value of enthalpy change (ΔHº) indicated the exothermic nature of the adsorption process, and the negative values of free energy change (ΔGº) were indicative of spontaneity of the adsorption process. In this work adsorption behaviour of SM and MN on activated carbon was also evaluated by the data obtained from column experiments.

Keywords: Acid, Activated Carbon, Adsorbent, Adsorbents, Adsorption, Adsorption Isotherms, Approach, Aqueous Solutions, Aqueous-Solutions, Batch Adsorption, Behaviour, Carbon, Column, Column Experiments, Coverage, Data, Desorption, Diffusion, Diffusion Model, Drinking-Water, Drug, Drugs, Energy, Enthalpy, Equilibrium, Exothermic, Experiments, First Order, Freundlich, Intraparticle Diffusion, Intraparticle Diffusion Model, Isotherms, Kinetic, Kinetic Model, Kinetic Models, Kinetics, Kinetics Of Adsorption, Lagergren Model, Langmuir, Langmuir Equation, Metronidazole, Mn, Model, Models, pH, pH Effect, Pharmaceutical Residues, Pharmaceuticals, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Pseudo-Second-Order Model, Range, Rate Constants, Removal, Risk-Assessment, Solution, Solutions, Sorption, Spent Bleaching Earth, Sulfamethoxazole, Surface, Surface Coverage, Temperature, Thermodynamic, Thermodynamic Parameters, Value, Waste-Water, Work

? Zhu, Z.L., Li, L., Zhang, H., Qiu, Y.L. and Zhao, J.F. (2010), Adsorption of lead and cadmium on ca-deficient hydroxyapatite. Separation Science and Technology, 45 (2), 262-268.

Full Text: 2010\Sep Sci Tec45, 262.pdf

Abstract: A Ca-deficient hydroxyapatite(d-HAp) has been used to remove lead and cadmium from their mixed ions solution. The effect of pH, coexistent calcium and magnesium ions, and humic acid on the adsorption efficiency were investigated. The results showed that this d-HAp adsorbed both Cd²⁺ and Pb²⁺ efficiently within a wide pH range. The existence of humic acid reduced the removal efficiency of Cd²⁺ and Pb²⁺. The addition of Ca²⁺ and Mg²⁺ with a concentration of 500 mg/L only slightly reduced the removal efficiency. The adsorption kinetics was described by pseudo-second-order reaction model and the adsorption isotherm followed the Langmuir model.

Keywords: Acid, Activated Carbon, Adsorption, Adsorption Isotherm, Adsorption Kinetics, Aqueous-Solutions, Biosorption, Ca-Deficient Hydroxyapatite, Cadmium, Calcium, Cd²⁺, Concentration, Copper(II), Efficiency, Heavy-Metals, Humic Acid, Hydroxyapatite, Ions, Isotherm, Kinetics, Langmuir, Langmuir Model, Lead, Magnesium, Model, Pb²⁺, pH, Pseudo Second Order, Pseudo-Second-Order, Range, Removal, Removal Efficiency, Solution, Sorption, Waste-Water

? Liu, Y., Li, H. and Zhu, X.H. (2010), Competitive Adsorption of Ag⁺, Pb²⁺, Ni²⁺, and Cd²⁺ Ions on Vermiculite. Separation Science and Technology,