Personal Research Database

Full Text: 2009\J Haz Mat162, 1457.pdf

Abstract: The purpose of this paper is to establish the experimental conditions for removal of several textile dyes from aqueous solutions by sorption on beech wood sawdust, an industrial waste lignocellulosic product. From the six dyes tested, the sorbent shows preference for three dyes: Direct Brown, Direct Brown 2 and Basic Blue 86. Sorption of dyes on the beech wood sawdust is dependent on the nature of dye, pH, dyes concentration, contact time, and amount of sorbent. By comparative kinetic studies, the rate of sorption was found to conform with good correlation to pseudo-second-order kinetics. The parameters that characterize the sorption were determined on the basis of Langmuir isotherms. The preference of beech sawdust for dyes increases as follows: Basic Blue 86 < Direct Brown 2 < Direct Brown. The maximum capacity of sorption of the commercial dye (of similar to 60% purity) was found to be 526.3 mg g^-1 for Direct Brown. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Aqueous Solutions, Aqueous-Solutions, Banana Pith, Basic-Dyes, Beech Wood Sawdust, Capacity, Concentration, Contact, Correlation, Dye, Dyes, Equilibrium Isotherms, Experimental, Fixed-Bed Systems, Isotherms, Kinetic, Kinetic Studies, Kinetics, Langmuir, Langmuir Isotherms, Low-Cost Adsorbents, Mar, Methylene-Blue, pH, Pine Sawdust, Preference, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-Second-Order, Pseudo-Second-Order Kinetics, Purity, Purpose, Removal, Rights, Sawdust, Solutions, Sorbent, Sorption, Textile Dyes, Waste, Waste-Water, Wood

? Hu, J., Chen, C.L., Zhu, X.X. and Wang, X.K. (2009), Removal of chromium from aqueous solution by using oxidized multiwalled carbon nanotubes. Journal of Hazardous Materials, 162 (2-3), 1542-1550.

Full Text: 2009\J Haz Mat162, 1542.pdf

Abstract: The batch removal of hexavalent chromium (Cr(VI)) from aqueous solution by using oxidized multiwalled carbon nanotubes (MWCNTs) was studied under ambient conditions. The effect of pH, initial concentration of Cr(VI), MWCNT content, contact time and ionic strength on the removal of Cr(VI) was also investigated. The removal was favored at low pH with maximum removal at pH Q. The adsorption kinetics was modeled by first-order reversible kinetics, pseudo-first-order kinetics, pseudo-second-order kinetics, and intraparticle diffusion models, respectively. The rate constants for all these kinetic models were calculated, and the results indicate that pseudo-second-order kinetics model was well suitable to model the kinetic adsorption of Cr(VI). The removal of chromium mainly depends on the occurrence of redox reaction of adsorbed Cr(VI) on the surface of oxidized MWCNTs to the formation of Cr(III), and subsequent the sorption of Cr(III) on MWCNTs appears as the leading mechanism for chromium uptake to MWCNTs. The presence of Cr(III) and Cr(VI) on oxidized MWCNTs was confirmed by the X-ray photoelectron spectroscopic analysis. The application of Langmuir and Freundlich isotherms are applied to fit the adsorption data of Cr(VI). Equilibrium data were well described by the typical Langmuir adsorption isotherm. Overall, the study demonstrated that MWCNTs can effectively remove Cr(VI) from aqueous solution under a wide range of experimental conditions, without significant Cr(III) release. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorption, Adsorption, Adsorption Isotherm, Adsorption Kinetics, Analysis, Application, Aqueous Solution, Batch, Carbon, Carbon Nanotubes, Chromium, Concentration, Contact, Cr(III), Cr(VI), Cr(VI) Removal, Data, Diffusion, Effect of pH, Equilibrium, Experimental, First Order, Freundlich, Hexavalent Chromium, Intraparticle, Intraparticle Diffusion, Ionic Strength, Isotherm, Isotherms, Kinetic, Kinetic Adsorption, Kinetic Models, Kinetics, Kinetics Model, Langmuir, Langmuir Adsorption Isotherm, Langmuir and Freundlich Isotherms, Mar, Mechanism, Model, Models, Multiwalled Carbon Nanotubes, Mwcnts, Nanoparticles, Nanotubes, pH, Product, Pseudo First Order, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-First-Order, Pseudo-First-Order Kinetics, Pseudo-Second-Order, Pseudo-Second-Order Kinetics, Rate Constants, Release, Removal, Rights, Solution, Sorption, Strength, Surface, Uptake, Waste-Water, Wastewater, X-Ray

? Zhang, W.M., Hong, C.H., Pan, B.C., Zhang, Q.J., Jiang, P.J. and Jia, K. (2009), Sorption enhancement of 1-naphthol onto a hydrophilic hyper-cross-linked polymer resin. Journal of Hazardous Materials, 163 (1), 53-57.

Full Text: 2009\J Haz Mat163, 53.pdf

Abstract: A hydrophilic hyper-cross-linked polymer resin NDA-150 was developed to remove 1-naphthol from the contaminated waters. The sorption performance of 1-naphthol on NDA-150 was explored and compared with that on the commercial hydrophobic resin XAD-4. The sorption rates of I-naphthol onto both of the two resins obey the pseudo-second-order kinetics, and are limited by the successive steps of film diffusion and intraparticle diffusion. The greater sorption rate on XAD-4 than NDA-150 is probably due to the larger average pore diameter of XAD-4. All the adsorption isotherms can be represented by Langmuir equation. The larger capacity and stronger affinity of NDA-150 than XAD-4 probably result from the abundant microporous structure and polar groups of NDA-150. In aqueous phase hydrophobic XAD-4 adsorbs 1-naphthol driven principally by enthalpy change, while the adsorption onto hydrophilic NDA-150 driven mainly by entropy change. The breakthrough and the total sorption capacity of NDA-150 to 1-naphthol were obtained to be 1.10 and 1.58 mmol ml^-1 resin at 293 K, respectively. Nearly 100% regeneration efficiency for the resin was achieved by ethanol at 313 K. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: 1-Naphthol, Acid, Activated Carbon, Adsorbents, Adsorption, Adsorption Isotherms, Aqueous Phase, Aqueous-Solution, Beads, Breakthrough, Capacity, Change, Diffusion, Efficiency, Enhancement, Enthalpy, Entropy, Ethanol, Extraction, Film, Film Diffusion, Intraparticle, Intraparticle Diffusion, Isotherms, Kinetics, Langmuir, Langmuir Equation, Performance, Phenolic-Compounds, Polymer, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-Second-Order, Pseudo-Second-Order Kinetics, Rates, Regeneration, Removal, Resin, Resins, Rights, Sorption, Sorption Capacity, Sorption Performance, Structure, Waters, XAD-4

? Yurtsever, M. and Şengil, İ.A. (2009), Biosorption of Pb(II) ions by modified quebracho tannin resin. Journal of Hazardous Materials, 163 (1), 58-64.

Full Text: 2009\J Haz Mat163, 58.pdf

Abstract: In this study, the effect of temperature, pH and initial metal concentration on Pb(II) biosorption on modified quebracho tannin resin (QTR) was investigated. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to investigate QTR structure and morphology. Besides, the specific BET surface area and zeta-potential of the QTR were analysed. Thermodynamic functions, the change of free energy (ΔG°). enthalpy (ΔH°) and entropy (ΔS°) of Pb adsorption on modified tannin resin were calculated as -5.43 kJ mol^-1 (at 296±2 K), 31.84 kJ mol^-1 and 0.127J mmol^-1 K^-1, respectively, indicating the spontaneous, endothermic and the increased randomness nature of Pb²⁺ adsorption. The kinetic data was tested using pseudo-first-order, pseudo-second-order. Elovich and intraparticle diffusion model. The results suggested that the pseudo-second-order model (R^-2 > 0.999) was the best choice among all the kinetic models to describe the adsorption behavior of Pb(II) onto QTR. Langmuir, Freundlich and Tempkin adsorption models were used to represent the equilibrium data. The best interpretation for the experimental data was given by the Langmuir isotherm and the maximum adsorption capacity (86.207 mg g^-1) of Pb(II) was obtained at pH 5 and 296 K. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Behavior, Adsorption Capacity, Aqueous-Solutions, Behavior, BET, BET Surface Area, Biosorption, Capacity, Change, Choice, Collagen Fiber Membrane, Concentration, Data, Diffusion, Diffusion Model, Electron Microscopy, Elovich, Endothermic, Energy, Enthalpy, Entropy, Equilibrium, Experimental, Freundlich, FTIR, Functions, Heavy-Metals, Infrared, Infrared Spectroscopy, Intraparticle, Intraparticle Diffusion, Intraparticle Diffusion Model, Ions, Isotherm, Isotherms, Kinetic, Kinetic Models, Kinetics, Langmuir, Langmuir Isotherm, Lead, Metal, Microscopy, Model, Models, Modified, Morphology, Natural Condensed Tannin, Pb, Pb(II), Pb(II) Ions, Pb²⁺, Pb²⁺ Adsorption, Persimmon Tannin, pH, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Quebracho Tannin Resin, Randomness, Recovery, Removal, Resin, Rights, SEM, Spectroscopy, Spontaneous, Structure, Surface, Surface Area, Tannin, Temperature, Tempkin, Thermodynamic, Waste-Water, Zeta Potential

? Ulusoy, U. and Akkaya, R. (2009), Adsorptive features of polyacrylamide-apatite composite for Pb²⁺, UO₂²⁺ and Th⁴⁺. Journal of Hazardous Materials, 163 (1), 98-108.

Full Text: 2009\J Haz Mat163, 98.pdf

Abstract: Micro-composite of polyacrylamide (PAA) and apatite (Apt) was prepared by direct polymerization of acrylamide in a suspension of Apt and characterized by means of FT-IR, XRD, SEM and BET analysis. The adsorptive features of PAA-Apt and Apt were then investigated for Pb²⁺, UO₂²⁺ and Th⁴⁺ in view of dependency on ion concentration, temperature, kinetics, ion selectivity and reusability. Experimentally obtained isotherms were evaluated with reference to Langmuir, Freundlich and Dubinin-Radushkevich (DR) models. Apt in PAA-Apt had higher adsorption capacity (0.81, 1.27 and 0.69 mol kg^-1) than bare Apt (0.28, 0.41 and 1.33 mol kg^-1) for Pb²⁺ and Th⁴⁺, but not for UO2²⁺. The affinity to PAA-Apt increased for Pb²⁺ and UO₂²⁺ but not changed for Th⁴⁺. The values of enthalpy and entropy changed were positive for all ions for both Apt and PAA-Apt. Free enthalpy change was ΔG<0. Well compatibility of adsorption kinetics to the pseudo-second-order model predicated that the rate-controlling step was a chemical sorption. This was consistent with the free energy values derived from DR model. The reusability tests for Pb²⁺ for five uses proved that the composite was reusable to provide a mean adsorption of 53.2 ± 0.7% from 410^-3 M Pb²⁺ solution and complete recovery of the adsorbed ion was possible (98 ± 1%). The results of this investigation suggested that the use of Apt in the micro-composite form with PAA significantly enhanced the adsorptive features of Apt. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Capacity, Adsorption Kinetics, Analysis, Apatite, Aqueous-Solutions, Barium Hydroxyapatite, BET, Capacity, Change, Chemical, Chemical Sorption, Composite, Concentration, Dependency, Energy, Enthalpy, Entropy, Freundlich, FT-IR, FTIR, Hydroxyapatite, Investigation, Ions, Isotherms, Kinetics, Langmuir, Lead Ions, Metal, Model, Models, Pb²⁺, Phosphate, Phytic Acid, Polyacrylamide, Polymerization, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Recovery, Reference, Removal, Rights, Selectivity, Sem, Solution, Sorption, Suspension, Temperature, Thorium, Uo₂²⁺, Uranium, Values, Water, X, XRD

? Hameed, B.H., Salman, J.M. and Ahmad, A.L. (2009), Adsorption isotherm and kinetic modeling of 2,4-D pesticide on activated carbon derived from date stones. Journal of Hazardous Materials, 163 (1), 121-126.

Full Text: 2009\J Haz Mat163, 121.pdf

Abstract: In this work, the adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) on activated carbon derived from date stones (DSAC) was studied with respect to pH and initial 2,4-D concentration. The experimental data were analyzed by the Freundlich isotherm, the Langmuir isotherm, and the Temkin isotherm. Equilibrium data fitted well with the Langmuir model with maximum adsorption capacity of 238.10 mg/g. Pseudo-first and pseudo-second-order kinetics models were tested with the experimental data, and pseudo-first-order kinetics was the best for the adsorption of 2,4-D by DSAC with coefficients of correlation R² ≥0.986 for all initial 2,4-D concentrations studied. The results indicated that the DSAC is very effective for the adsorption of 2,4-D from aqueous solutions. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: 2,4-D, 2,4-Dichlorophenoxy-Acetic Acid, Activated Carbon, Adsorption, Adsorption Capacity, Adsorption Isotherm, Aqueous Solutions, Aqueous-Solution, Bagasse Fly-Ash, Capacity, Carbon, Concentration, Correlation, Data, Date Stone, Degradation, Dye, Equilibrium, Experimental, Fixed-Bed, Freundlich, Freundlich Isotherm, Isotherm, Kinetic, Kinetic Modeling, Kinetics, Kinetics Models, Langmuir, Langmuir Isotherm, Langmuir Model, Methylene-Blue, Model, Modeling, Models, Pesticide, pH, Pseudo First Order, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-First-Order, Pseudo-First-Order Kinetics, Pseudo-Second-Order, Pseudo-Second-Order Kinetics, Removal, Rights, Solutions, Sorption, Sugar-Industry Waste, Temkin Isotherm, Water, Work

? Rakhshaee, R., Giahi, M. and Pourahmad, A. (2009), Studying effect of cell wall’s carboxyl-carboxylate ratio change of Lemna minor to remove heavy metals from aqueous solution. Journal of Hazardous Materials, 163 (1), 165-173.

Full Text: 2009\J Haz Mat163, 165.pdf

Abstract: The pre-treated Lemna minor can remove Hg(II), Cr(III), Cr(VI) and Cu(II) from the aqueous solution. The concentration determination of carboxyl and carboxylate groups and its rule to change the metal ions uptake was done by the curves of the potentiometric titration. It was shown that the removal percent of the heavy metal ions (Co = 1.00 mM) increased 25.1, 26.0, 17.2 and 24.1% for these ions, respectively, with increasing the carboxylate from 0.92 to 2.42 mmol/gL minor and then activating by the activator chloride salts. The removal percent of these ions was decreased 33.1, 27.5, 20.7 and 15.01%, respectively, with increasing the carboxyl from 1.50 to 2.41 mmol/gL minor, inspite of activating by the chloride salts. The enthalpy change (Δ H) was -27.43, -25.94, -28.12 and -22.27 kJ/mol and the entropy change (Δ S) was 81.3. 79.9, 86.1 and 67.7 J/mol K, by activated biomass, respectively. L minor removed these heavy metals corresponding to pseudo-second-order kinetic model that the activation energy (E-a) was obtained 18.59, 15.93, 20.36 and 21.12 kJ/mol by the activated and 23.02, 22.27, 23.98 and 24.46 kj/mol by the reference biomass to uptake Hg(II), Cr(III). Cr(VI) and Cu(II), respectively. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: Activation, Activation Energy, Activator, Aqueous Solution, Arrhizus, Azolla-Filiculoides, Biomass, Cadmium(II) Biosorption, Cd(II), Cell Wall Activation, Change, Chloride, Co, Concentration, Cr(III), Cr(VI), Cu(II), Determination, Energy, Enthalpy, Entropy, Equilibrium, Heavy Metal, Heavy Metal Ions, Heavy Metals, Heavy Metals Biosorption, Hg(II), Ions, Kinetic, Kinetic Model, Kinetic Parameters, Lead(II), Lemna Minor, Marine-Algae, Metal, Metal Ions, Metals, Minor, Model, Pectins, Potentiometric Titration, Pseudo Second Order, Pseudo Second Order Kinetic, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Reference, Removal, Rights, Salts, Seaweed, Solution, Thermodynamic Study, Uptake

? Tunç, Ö., Tanacı, H. and Aksu, Z. (2009), Potential use of cotton plant wastes for the removal of Remazol Black B reactive dye. Journal of Hazardous Materials, 163 (1), 187-198.

Full Text: 2009\J Haz Mat163, 187.pdf

Abstract: In this study, the potential use of cotton plant wastes - stalk (CS) and hull (CH) - as sorbents for the removal of Remazol Black B(RB5), a vinyl sulfone type reactive dye, was investigated. The results indicated that adsorption was strongly pH-dependent but slightly temperature-dependent for each sorbent-dye system. The Freundlich, Langmuir, Redlich-Peterson and Langmuir-Freundlich adsorption models were used for the mathematical description of adsorption equilibrium and isotherm constants were evaluated at 25C. All models except the Freundlich model were applicable for the description of dye adsorption by both sorbents in the concentration range studied. According to the Langmuir model, CS and CH sorbents exhibited the highest RB5 dye uptake capacities of 35.7 and 50.9mg g^-1, respectively, at an initial pH value of 1.0. Simple mass transfer and kinetic models were applied to the experimental data to examine the mechanisms of adsorption and potential rate-controlling steps. It was found that both external mass transfer and intra-particle diffusion played an important role in the adsorption mechanisms of dye, and adsorption kinetics followed the pseudo second-order type kinetic model for each sorbent. Using the Langmuir model parameters, thermodynamic constant G° was also evaluated for each sorption system. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: Acid, Activated Carbon, Adsorption, Adsorption, Adsorption Equilibrium, Adsorption Kinetics, Adsorption Mechanisms, Anionic Dye, Aqueous-Solution, Biosorption, Black, Concentration, Corynebacterium-Glutamicum, Cotton Plant Wastes, Data, Diffusion, Dye, Dye Adsorption, Equilibrium, Experimental, Freundlich, Freundlich Model, Intra-Particle Diffusion, Intraparticle, Intraparticle Diffusion, Isotherm, Isotherms, Kinetic, Kinetic Model, Kinetic Models, Kinetics, Kinetics, Langmuir, Langmuir Model, Langmuir-Freundlich, Mass, Mass Transfer, Mechanisms, Model, Models, pH, pH Value, pH-Dependent, Plant, Plant Wastes, Potential, Pseudo, Pseudo Second Order, Pseudo Second-Order, Pseudo-Second-Order, Rb5, Reactive Dye, Redlich-Peterson, Remazol Black B, Removal, Rice-Husk, Rights, Role, Second Order, Second-Order, Sorbent, Sorbents, Sorption, Sulfone, Thermodynamic, Uptake, Value

? Aguado, J., Arsuaga, J.M., Arencibia, A., Lindo, M. and Gascón, V. (2009), Aqueous heavy metals removal by adsorption on amine-functionalized mesoporous silica. Journal of Hazardous Materials, 163 (1), 213-221.

Full Text: 2009\J Haz Mat163, 213.pdf

Abstract: Amino functional mesoporous silica SBA-15 materials have been prepared to develop efficient adsorbents of heavy metals in wastewater. Functionalization with amino groups has been carried out by using two independent methods, grafting and co-condensation. Three organic moieties have been selected to incorporate the active amino sites: aminopropyl (H₂N-(CH₂)₃-), [2-aminoethylamino]-propyl (H₂N-(CH₂)₂-NH-(CH₂)₃-) and [(2-aminoethylamino)-ethylamino]-propyl (H₂N-(CH₂)₂-NH-(CH₂)₂-NH-(CH₂)₃-). Materials have been characterized by XRD, nitrogen sorption measurements and chemical analysis. We have found that all materials preserve the mesoscopic order and exhibit suitable textural properties and nitrogen contents to act as potential adsorbents. Metal removal from aqueous solution has been examined for Cu(II), Ni(II), Pb(II), Cd(II), and Zn(II); adsorption performances of materials prepared by the two functionalization methods have been compared. In addition, copper adsorption process has been thoroughly studied from both kinetic and equilibrium points of view for some selected materials. Aqueous Cu(II) adsorption rates show that the overall process is fast and the time evolution can be successfully reproduced with a pseudo-second-order kinetic model. Whole copper adsorption isotherms have been obtained at 25C. Significant maximum adsorption capacities have been found with excellent behavior at low concentration. (C) 2008 Elsevier B.V. All rights reserved.

Keywords: Adsorbents, Adsorption, Adsorption Capacities, Adsorption Isotherms, Adsorption Process, Amine-Functionalized SBA-15, Analysis, Aqueous Solution, Behavior, Capacity, Cd(II), Chemical, Chemical Analysis, CO₂ Adsorbents, Concentration, Copper, Copper Adsorption, Cu(II), Design, Equilibrium, Evolution, Functionalization, Grafting, Heavy Metal Removal, Heavy Metals, Ions, Isotherms, Kinetic, Kinetic Model, Mercury(II), Mesoporous, Mesoporous Silica, Metal, Metal Removal, Metals, Metals Removal, Methods, Model, Molecular-Sieves, Monolayers, Ni(II), Nitrogen, Organic, Pb(II), Potential, Process, Pseudo Second Order, Pseudo Second Order Kinetic, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Rates, Remediation, Removal, Rights, Sba-15, Silica, Solution, Sorption, Templating Route, Wastewater, Wastewater Treatment, XRD, Zn(II)

? Gupta, V.K. and Rastogi, A. (2009), Biosorption of hexavalent chromium by raw and acid-treated green alga Oedogonium hatei from aqueous solutions. Journal of Hazardous Materials, 163 (1), 396-402.

Full Text: 2009\J Haz Mat163, 396.pdf

Abstract: The hexavalent chromium, Cr(VI), biosorption by raw and acid-treated Oedogonium hatei were studied from aqueous solutions. Batch experiments were conducted to determine the biosorption properties of the biomass. The optimum conditions of biosorption were found to be: a biomass dose of 0.8 g/L, contact time of 110 min, pH and temperature 2.0 and 318 K respectively. Both Langmuir and Freundlich isotherm equations could fit the equilibrium data. Under the optimal conditions, the biosorption capacities of the raw and acid-treated algae were 31 and 35.2 mg Cr(VI) per g of dry adsorbent. respectively. Thermodynamic parameters showed that the adsorption of Cr(VI) onto algal biomass was feasible, spontaneous and endothermic under studied conditions. The pseudo-first-order kinetic model adequately describe the kinetic data in comparison to second-order model and the process involving rate-controlling step is much complex involving both boundary layer and intra-particle diffusion processes. The physical and chemical properties of the biosorbent were determined and the nature of biomass-metal ions interactions were evaluated by FTIR analysis, which showed the participation of -CCOH, -OH and -NH2 groups in the biosorption process. Biosorbents could be regenerated using 0.1 M NaOH solution, with up to 75% recovery. Thus, the biomass used in this work proved to be effective materials for the treatment of chromium bearing aqueous solutions. (c) 2008 Elsevier B.V. All rights reserved.

Keywords: Activated-Sludge, Adsorbent, Adsorption, Algae, Analysis, Aqueous Solutions, Biomass, Biosorbent, Biosorption, Boundary Layer, Chemical, Chromium, Comparison, Contact, Cr(VI), Data, Diffusion, Diffusion Processes, Endothermic, Equilibrium, Experiments, Freundlich, Freundlich Isotherm, FTIR, FTIR Analysis, Green Alga, Hexavalent Chromium, Industrial-Waste, Interactions, Intra-Particle Diffusion, Intraparticle, Intraparticle Diffusion, Ion-Exchange, Ions, Isotherm, Isotherm Equations, Kinetic, Kinetic Model, Kinetic Models, Langmuir, Model, NAOH, NH₂, Oedogonium Hatei, OH, Optimal Conditions, Participation, pH, Physical, Process, Pseudo First Order, Pseudo-First-Order, Recovery, Removal, Rights, Second Order, Second-Order, Second-Order Model, Solution, Solutions, Sorption, Spontaneous, Temperature, Thermodynamic, Thermodynamic Parameters, Treatment, Waste-Water, Work

? Erdem, B., Özcan, A., Gök, O. and Özcan, S. (2009), Immobilization of 2,2’-dipyridyl onto bentonite and its adsorption behavior of copper(II) ions. Journal of Hazardous Materials, 163 (1), 418-426.

Full Text: 2009\J Haz Mat163, 418.pdf

Abstract: In this study, the immobilization of 2,2’-dipyridyl onto bentonite was firstly carried out and it was then used for the adsorption of copper(II) ions from aqueous solutions. The variation of the parameters of pH, contact time, initial copper(II) concentration and temperature were investigated in the adsorption experiments. The XRD. FTIR, elemental and thermal analyses were performed to observe the immobilization of 2,2’-dipyridyl onto natural bentonite. The adsorption data obtained were well described by the Langmuir adsorption isotherm model at all studied temperatures. The results indicated that the maximum adsorption capacity was 54.07 mg g^-1 from the Langmuir isotherm model at 50C. The thermodynamic parameters indicated that the adsorption process is spontaneous, endothermic and chemical in nature. The kinetic parameters of the adsorption were calculated from the experimental data. According to these parameters, the best-fit was obtained by the pseudo-second-order kinetic model. The results showed that 2,2’-dipyridyl-immobilized bentonite can be used as the effective adsorbent for the removal of heavy metal contaminants. (c) 2008 Elsevier B.V. All rights reserved.

Keywords: 2,2’-Dipyridyl, Acid Dyes, Adsorbent, Adsorption, Adsorption Behavior, Adsorption Capacity, Adsorption Isotherm, Adsorption Isotherm Model, Adsorption Process, Analyses, Aqueous Solutions, Aqueous-Solutions, Behavior, Bentonite, Cadmium Ions, Capacity, Chemical, Clay, Concentration, Contact, Contaminants, Copper, Copper(II), Data, Desorption Characteristics, Endothermic, Experimental, Experiments, FTIR, Heavy Metal, Heavy-Metal Cations, Immobilization, Ions, Isotherm, Isotherm Model, Kinetic, Kinetic Model, Kinetic Parameters, Langmuir, Langmuir Adsorption Isotherm, Langmuir Isotherm, Langmuir Isotherm Model, Metal, Model, Montmorillonite, Natural, Natural Zeolites, pH, Process, Pseudo Second Order, Pseudo Second Order Kinetic, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Removal, Rights, Solutions, Sorption, Spontaneous, Temperature, Thermodynamic, Thermodynamic Parameters, XRD

? Aziz, A., Ouali, M.S., Elandaloussi, E.H., De Menorval, L.C. and Lindheimer, M. (2009), Chemically modified olive stone: A low-cost sorbent for heavy metals and basic dyes removal from aqueous solutions. Journal of Hazardous Materials,