Personal Research Database

Full Text: 2008\J Haz Mat150, 546.pdf

Abstract: The silica gel surface immobilized with 4-phenylacetophynone 4-aminobenzoylhydrazone (PAAH) after surface modification by 3-chloropropyltrimethoxysilane (CPTS). The modified silica gel was used for sorption of Cu(II), Ni(II) and Co(II) in aqueous solution. The effect of solution pH, sorption time, temperature and initial metal ion concentration onto metal ions sorption was investigated. The characteristics of the sorption process were evaluated by using the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) adsorption isotherms. The sorption of metal ions onto modified silica gel correlated well with the Langmuir type adsorption isotherm and adsorption capacities were found to be 0.012, 0.014 and 0.018 mmol g^-1 for Cu(II), Ni(II) and Co(II) metal ions, respectively. From the D-R adsorption isotherms, it was concluded that chemical interactions and chelating effects were playing an important role in the sorption of metal ions onto modified silica gel. Thermodynamic parameters such as the standard free energy change (G), enthalpy change (H) and entrophy change (S) were calculated to determine the nature of sorption process. From these parameters, H were found to be endothermic values: 38.39, 18.0, and 14.7 kJ mol^-1 for the same sequence of divalent cations and S values were calculated to be positive for the sorption of each metal ion onto the modified silica gel. Negative G values indicated that sorption process for all metal ions were spontaneous in nature although they presented an endothermic enthalpy for the interaction, resulting in an entropically favoured process. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Capacities, Adsorption Isotherm, Adsorption Isotherms, Application, Aqueous Solution, Aqueous-Solutions, Characteristics, Chemical, Co(II), Cobalt, Concentration, Copper, Copper Ions, Cu(II), D-R Isotherm, Divalent-Cations, Endothermic, Energy, Enthalpy, Freundlich, Freundlich Isotherm, Gel, Immobilization, Immobilized, Interaction, Isotherm, Isotherms, Langmuir, Langmuir Isotherm, Matrix, Metal, Metal Ions, Modification, Modified, Ni(II), Nickel, pH, Removal, Rights, Role, Separation, Silica, Silica Gel, Solid, Liquid Interface, Solution, Sorption, Sorption Process, Standard, Surface, Surface Modification, Synthesis, Temperature, Thermodynamic, Thermodynamic Parameters

? Argun, M.E. (2008), Use of clinoptilolite for the removal of nickel ions from water: Kinetics and thermodynamics. Journal of Hazardous Materials, 150 (3), 587-595.

Full Text: 2008\J Haz Mat150, 587.pdf

Abstract: This paper describes the removal of Ni(II) ions from aqueous solutions using clinoptilolite. The effect of clinoptilolite level, contact time, and pH were determined. Different isotherms were also obtained using concentrations of Ni(II) ions ranging from 0.1 to 100 mg L^-1. The ion-exchange process follows second-order reaction kinetics and follows the Langmuir isotherm. The paper discusses thermodynamic parameters, including changes in Gibbs free energy, entropy, and enthalpy, for the ion-exchange of Ni(II) on clinoptilolite, and revealed that the ion-exchange process was spontaneous and exothermic under natural conditions. The maximum removal efficiency obtained was 93.6% at pH 7 and with a 45 min contact time (for 25 mg L^-1 initial concentration and a 15 g L^-1 solid-to-liquid ratio). (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Aqueous Solutions, Aqueous-Solutions, Bentonite, Biosorption, Clay, Clinoptilolite, Equilibrium, Ion Exchange, Ion-Exchange, Isotherm, Isotherms, Kinetics, Langmuir, Langmuir Isotherm, Nickel, Nickel Removal, pH, Reaction Kinetics, Removal, Removal Efficiency, Sorption, Thermodynamic Parameters, Thermodynamics, Waste-Water, Water

? Meena, A.K., Kadirvelu, K., Mishra, G.K., Rajagopal, C. and Nagar, P.N. (2008), Adsorptive removal of heavy metals from aqueous solution by treated sawdust (Acacia arabica). Journal of Hazardous Materials, 150 (3), 604-611.

Full Text: 2008\J Haz Mat150, 604.pdf

Abstract: The removal of Cr(VI), Pb(II), Hg(II) and Cu(II), by treated sawdust has been found to be concentration, pH, contact time, adsorbent dose and temperature dependent. The adsorption parameters were determined using both Langmuir and Freundlich isotherm models. Adsorption capacity for treated sawdust, i.e. Cr(VI) (111.61 mg/g), Pb(II) (52.38 mg/g), Hg(II) (20.62 mg/g), and Cu(II) (5.64 mg/g), respectively. Surface complexation and ion exchange are the major removal mechanisms involved. The adsorption isotherm studies clearly indicated that the adsorptive behaviour of metal ions on treated sawdust satisfies not only the Langmuir assumptions but also the Freundlich assumptions. The applicability of Lagergren kinetic model has also been investigated. The adsorption follows first-order kinetics. Thermodynamic constant (k(ad)), standard free energy (G), enthalpy (H) and entropy (S) were calculated for predicting the nature of adsorption. The percentage adsorption increases with pH to attain a maximum at pH 6 and thereafter it decreases with further increase in pH. The results indicate the potential application of this method for effluent treatment in industries and also provide strong evidence to support the adsorption mechanism proposed. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Acacia Arabica, Activated Carbon, Adsorbent, Adsorbent Dose, Adsorption, Adsorption Capacity, Adsorption Isotherm, Adsorption Mechanism, Application, Aqueous Solution, Assumptions, Behaviour, Capacity, Coirpith, Complexation, Concentration, Contact, Copper, Cr(VI), Cu(II), Energy, Enthalpy, Entropy, Evidence, Exchange, First Order, First-Order Kinetics, Fixed-Bed, Freundlich, Freundlich Isotherm, Heavy Metals, Hg(II), Ion Exchange, Ion-Exchange, Ions, Isotherm, Isotherm Models, Isotherms, Kinetic, Kinetic Model, Kinetics, Kinetics, Lagergren, Langmuir, Mechanism, Mechanisms, Mercury(II), Metal, Metal Ions, Metals, Model, Models, Ni(II), Nickel(II), Pb(II), pH, Potential, Removal, Rights, Sawdust, Solution, Standard, Support, Temperature, Thermodynamic, Time, Treatment, Waste

? Meena, A.K., Kadirvelu, K., Mishraa, G.K., Rajagopal, C. and Nagar, P.N. (2008), Adsorption of Pb(II) and Cd(II) metal ions from aqueous solutions by mustard husk. Journal of Hazardous Materials, 150 (3), 619-625.

Full Text: 2008\J Haz Mat150, 619.pdf

Abstract: Abstract: The adsorption of Pb(II) and Cd(II) metal ions on mustard husk has been found to be concentration, pH, contact time, adsorbent dose and temperature dependent. The adsorption parameters were determined using Langmuir and Freundlich isotherm models. The adsorption isotherm studies clearly indicated that the adsorptive behavior of Pb(II) and Cd(II) metal ions on mustard husk satisfies not only the Langmuir assumptions but also the Freundlich assumptions, i.e. multilayer formation on the surface of the adsorbent with an exponential distribution of site energy. Ion exchange and surface complexation are the major adsorption mechanisms involved.

The applicability of Lagergren kinetic model has also been investigated. Themodynamic constant (k(ad)), free energy change (G), enthalpy change (H) and entropy change (S) were calculated for predicting the nature of adsorption. The results indicate the potential application of this method for effluent treatment in industries and also provide strong evidence to support the adsorption mechanism proposed. (c) 2007 Published by Elsevier B.V.

Keywords: Activated Carbon, Adsorbent, Adsorbent Dose, Adsorption, Adsorption Isotherm, Adsorption Mechanism, Adsorption Mechanisms, Adsorption of Pb(II), Application, Aqueous Solutions, Assumptions, Behavior, Cadmium, Cd(II), Change, Complexation, Concentration, Contact, Copper, Distribution, Energy, Enthalpy, Entropy, Evidence, Exchange, Freundlich, Freundlich Isotherm, Heavy-Metals, Ion Exchange, Ion-Exchange, Ions, Isotherm, Isotherm Models, Isotherms, Kinetic, Kinetic Model, Kinetics, Lagergren, Langmuir, Lead, Mechanism, Mechanisms, Mercury, Metal, Metal Ions, Metals Ions, Model, Models, Multilayer, Mustard Husk, Pb(II), pH, Potential, Removal, Site, Solutions, Sorption, Support, Surface, Surface Complexation, Temperature, Time, Treatment, Waste, Wastewater

? Singh, K.P., Malik, A., Sinha, S. and Ojha, P. (2008), Liquid-phase adsorption of phenols using activated carbons derived from agricultural waste material. Journal of Hazardous Materials, 150 (3), 626-641.

Full Text: 2008\J Haz Mat150, 626.pdf

Abstract: Physical and chemical properties of activated carbons prepared from coconut shells (SAC and ATSAC) were studied. The adsorption equilibria and kinetics of phenol and 2,4-dichlorophenol from aqueous solutions on such carbons were then examined at three different temperatures (10, 25 and 40C. Adsorption of both phenol and 2,4-dichlorophenol increased with an increase in temperature. The experimental data were analyzed using the Langmuir and Freundlich isotherm models. Both the isotherm models adequately fit the adsorption data for both the phenols. The carbon developed through the acid treatment of coconut shells (ATSAQ exhibited relatively higher monolayer adsorption capacity for phenol (0.53 mmol g^-1) and 2,4-dichlorophenol (0.31 mmol g^-1) as compared to that developed by thermal activation (SAC) with adsorption capacity of 0.36 and 0.20 mmol g^-1, for phenol and 2.4-dichlorophenol, respectively. The equilibrium sorption and kinetics model parameters and thermodynamic functions were estimated and discussed. The thermodynamic parameters (free energy, enthalpy and entropy changes) exhibited the feasibility and spontaneous nature of the adsorption process. The sorption kinetics was studied using the pseudo-first-order and second-order kinetics models. The adsorption kinetics data for both the phenol and 2,4-dichlorophenol fitted better to the second-order model. An attempt was also made to identify the rate-limiting step involved in the adsorption process. Results of mass transfer analysis suggested the endothermic nature of the reaction and change in the mechanism with time and initial concentration of the adsorbate. The results of the study show that the activated carbons derived from coconut shells can be used as potential adsorbent for phenols in water/wastewater. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbons, Activation, Adsorbent, Adsorption, Adsorption Kinetics, Analysis, Aqueous Solutions, Aqueous-Solutions, Carbon, Coconut Shell, Color Removal, Equilibria, Equilibrium, Freundlich Isotherm, Isotherm, Kinetics, Langmuir, Mass Transfer, Mechanism, Mechanisms, Oil-Shale, P-Nitrophenol, Pentachlorophenol, Peroxidase, Phenol, Phenols, Sorption, Step Steam Pyrolysis, Temperature, Thermodynamic Parameters, Water

? Long, C., Lu, J.D., Li, A.M., Hu, D.B., Liu, F.Q. and Zhang, Q.X. (2008), Adsorption of naphthalene onto the carbon adsorbent from waste ion exchange resin: Equilibrium and kinetic characteristics. Journal of Hazardous Materials, 150 (3), 656-661.

Full Text: 2008\J Haz Mat150, 656.pdf

Abstract: Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants that can result in serious health problems and genetic defects in humans. In this research, a spherical microporous carbon adsorbent (CR-1) had been obtained by carbonization and activation of the waste polysulfonated cation exchange resin. Naphthalene was adopted as a model compound to examine the adsorption effectiveness for removing PAHs from the aqueous solution by CR-1. Nonlinear isotherms models, i.e., Freundlich, Langmuir, Brunauer-Emmett-Teller and Polanyi-Dubinin-Manes models were tested to fit experimental data. The adsorption equilibrium data of naphthalene on CR-1 was fitted well by the Polanyi-Dubinin-Manes model. Through both isotherm modeling and constructing “characteristic curve”, Polanyi theory was useful to describe the adsorption process of naphthalene by CR-1. providing evidence that a micropore filling phenomenon is involved. In addition, among the tested kinetic models in this study (e.g., pseudo-first-order and pseudo-second-order equations), the pseudo-first-order equation successfully predicted the kinetic adsorption process. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbons, Activation, Adsorbent, Adsorption, Adsorption Equilibrium, Aqueous Solution, Aqueous-Solution, Carbon, Carbonization, Cation, Cation Exchange, Degradation, Environmental, Equilibrium, Ion Exchange, Ion-Exchange, Isotherm, Isotherms, Kinetic, Kinetic Models, Kinetics, Langmuir, Modeling, Naphthalene, Pentachlorophenol, Polanyi Theory, Polycyclic Aromatic-Hydrocarbons, Research, Solution, Sorption, Theory, Waste Ion Exchange Resin, Water

? Pavan, F.A., Lima, E.C., Dias, S.L.P. and Mazzocato, A.C. (2008), Methylene blue biosorption from aqueous solutions by yellow passion fruit waste. Journal of Hazardous Materials, 150 (3), 703-712.

Full Text: 2008\J Haz Mat150, 703.pdf

Abstract: The yellow passion fruit (Passiflora edulis Sims. f. flavicarpa Degener) (YPFW) a powdered solid waste, was tested as biosorbent for the removal of a cationic dye, methylene blue (MB), from aqueous solutions. Adsorption of MB onto this low-cost natural adsorbent was studied by batch adsorption at 25C. The effects of shaking time, biosorbent dosage and pH on adsorption capacity were studied. In alkaline pH region the adsorption of MB was favorable. The contact time required to obtain the maximum adsorption was 48 It at 25C. Four kinetic models were tested, being the adsorption kinetics better fitted to pseudo-first order and ion exchange kinetic models. The ion exchange and pseudo-first order constant rates were 0.05594 and 0.05455 h^-1, respectively. The equilibrium data were fitted to Langmuir, Freundlich, Sips and Redlich-Peterson isotherm models. Taking into account the analysis of the normal distribution of the residuals (difference of q(measured) - q(model)), the data were best fitted to Sips isotherm model. The maximum amount of MB adsorbed on YPFW biosorbent was 44.70 mg g^-1 (c) 2007 Published by Elsevier B.V.

Keywords: Adsorbent, Adsorption, Adsorption Capacity, Adsorption Kinetics, Analysis, Aqueous Solution, Aqueous Solutions, Batch, Batch Adsorption, Biosorbent, Biosorption, Capacity, Cationic Dye, Data, Distribution, Dye, Equilibrium, Freundlich, Ion Exchange, Ion-Exchange, Isotherm, Isotherm Model, Isotherm Models, Kinetic, Kinetic Models, Kinetics, Langmuir, Low Cost, Low-Cost Adsorbent, MB, Methylene Blue, Model, Models, Natural, Natural Adsorbent, Normal, pH, Pseudo First Order, Pseudo-First Order, Pseudo-First-Order, Rates, Redlich-Peterson, Removal, Residuals, Solid Waste, Solutions, Waste, Yellow Passion-Fruit Waste

? Dizge, N., Aydiner, C., Demirbas, E., Kobya, M. and Kara, S. (2008), Adsorption of reactive dyes from aqueous solutions by fly ash: Kinetic and equilibrium studies. Journal of Hazardous Materials, 150 (3), 737-746.

Full Text: 2008\J Haz Mat150, 737.pdf

Abstract: Adsorption kinetic and equilibrium studies of three reactive dyes namely, Remazol Brillant Blue (RB), Remazol Red 133 (RR) and Rifacion Yellow HED (RY)from aqueous solutions at various initial dye concentration (100-500 mg/l), pH(2-8), particle size (45-112.5 m) and temperature (293-323 K) on fly ash (FA) were studied in a batch mode operation. The adsorbent was characterized with using several methods such as SEM, XRD and FTIR. Adsorption of RB reactive dye was found to be pH dependent but both RR and RY reactive dyes were not. The result showed that the amount adsorbed of the reactive dyes increased with increasing initial dye concentration and contact time. Batch kinetic data from experimental investigations on the removal of reactive dyes from aqueous solutions using FA have been well described by external mass transfer and intraparticle diffusion models. It was found that external mass transfer and intraparticle diffusion had rate limiting affects on the removal process. This was attributed to the relatively simple macropore structure of FA particles. The adsorption data fitted well with Langmuir and Freundlich isotherm models. The optimum conditions for removal of the reactive dyes were 100 mg/l initial dye concentration, 0.6 g/100 ml adsorbent dose, temperature of 293 K, 45 mu m particle size, pH 6 and agitation speed of 250 rpm, respectively. The values of Langmuir and Freundlich constants were found to increase with increasing temperature in the range 135-180 and 15-34 mg/g for RB, 47-86 and 1.9-3.7 mg/g for RR and 37-61 and 3.0-3.6 mg/g for RY reactive dyes, respectively. Different thermodynamic parameters viz., changes in standard free energy, enthalpy and entropy were evaluated and it was found that the reaction was spontaneous and endothermic in nature. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Adsorbent Dose, Adsorption, Adsorption Isotherms, Adsorption Kinetic, Agitation, Aqueous Solutions, Batch, Batch Mode, Changes, Color Removal, Concentration, Congo Red, Data, Diffusion, Dye, Dyes, Endothermic, Energy, Enthalpy, Entropy, Equilibrium, Equilibrium Studies, Experimental, External Diffusion, Fly Ash, Freundlich, Freundlich Isotherm, FTIR, Green-Dye, Intraparticle Diffusion, Investigations, Isotherm, Isotherm Analyses, Kinetic, Langmuir, Low-Cost Adsorbent, Mass, Mass Transfer, Methods, Methylene-Blue, Mode, Models, Operation, Particle Size, Particles, pH, pH-Dependent, Reactive Dye, Reactive Dyes, Removal, Rights, SEM, Size, Solutions, Sorption, Standard, Structure, Temperature, Textile Effluents, Thermodynamic, Thermodynamic Parameters, Waste-Water, XRD

? Shakir, K., Ghoneimy, H.F., Elkafrawy, A.F., Beheir, S.G. and Refaat, M. (2008), Removal of catechol from aqueous solutions by adsorption onto organophilic-bentonite. Journal of Hazardous Materials, 150 (3), 765-773.

Full Text: 2008\J Haz Mat150, 765.pdf

Abstract: Organophilic-bentonite, produced by exchange of cetyltrimethylammonium cation for metal cations on the bentonite, was exploited as adsorbent for removal of catechol from aqueous solutions using batch technique. The dependence of removal on various physico-chemical parameters, such as contact time (1-250 min), concentration (0.8-15.3 mmol L-1), temperature (30, 40, 50 +/- 1 degrees C and pH (5-12) of the adsorptive solution were investigated. Obtained results show that catechol could be removed efficiently (similar to 100%) at pH values >= 9.9. The uptake process follows first-order rate kinetics and the equilibrium data fit well into the Langmuir and Freundlich adsorption isotherms over a wide range of concentration (1-10 mmol L-1). The magnitude of change of free energy (Delta G degrees), enthalpy (Delta H degrees) and entropy (Delta S degrees) were determined. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Isotherms, Bentonite, Catechol Removal, Cation, Energy, Equilibrium, Exchange, First Order, Freundlich, Isotherms, Kinetics, Kinetics, Langmuir, Metal, Montmorillonite, Organic Contaminants, Organophilic-Bentonite, Ph, Phenol, Phenols, Quaternary Ammonium Salts, Quinones, Removal, Sorption, Thermodynamics, Uptake, Water

? Zhang, J., Li, Y., Zhang, C.L. and Jing, Y.M. (2008), Adsorption of malachite green from aqueous solution onto carbon prepared from Arundo donax root. Journal of Hazardous Materials, 150 (3), 774-782.

Full Text: 2008\J Haz Mat150, 774.pdf

Abstract: Arundo donax root carbon (ADRC), a new adsorbent, was prepared from Arundo donax root by carbonization. The surface area of the adsorbent was determined 158 m²/g by N-2 adsorption isotherm. Batch adsorption experiments were carried out for the removal of malachite green (MG) from aqueous solution using ADRC as adsorbent. The effects of various parameters such as solution pH (3-10), carbon dose (0.15-1.0 g/100 ml) and initial MG concentration (10-100 mg/l) on the adsorption system were investigated. The effective pH was 5-7 and the optimum adsorbent dose was found to be 0.6 g/100 ml. Equilibrium experimental data at 293, 303 and 313 K were better represented by Langmuir isotherm than Freundlich isotherm using linear and non-linear methods. Thermodynamic parameters such as G, H and S were also calculated. The negative Gibbs free energy change and the positive enthalpy change indicated the spontaneous and endothermic nature of the adsorption. The adsorption equilibrium time was 180 min. Adsorption kinetics was determined using pseudo-first-order model, pseudo-second-order model and intraparticle diffusion model. The results showed that the adsorption of MG onto ADRC followed pseudo-second-order model. (c) 2007 Published by Elsevier B.V.

Keywords: Adsorbent, Adsorbent Dose, Adsorption, Adsorption Equilibrium, Adsorption Isotherm, Adsorption Kinetics, Aqueous Solution, Arundo Donax Root Carbon, Batch Adsorption, Carbon, Carbonization, Concentration, Data, Diffusion, Diffusion Model, Endothermic, Energy, Enthalpy, Equilibrium, Equilibrium Time, Experimental, Experiments, Freundlich, Freundlich Isotherm, Gibbs Free Energy, Intraparticle Diffusion, Intraparticle Diffusion Model, Isotherm, Kinetics, Langmuir, Langmuir Isotherm, Malachite Green, Methods, Mg, Model, N₂, N₂ Adsorption, pH, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Removal, Solution, Surface, Surface Area, Thermodynamic, Thermodynamic Parameters

? Sheha, R.R. and El-Zahhar, A.A. (2008), Synthesis of some ferromagnetic composite resins and their metal removal characteristics in aqueous solutions. Journal of Hazardous Materials, 150 (3), 795-803.

Full Text: 2008\J Haz Mat150, 795.pdf

Abstract: In this study, a procedure for synthesis of new organic-inorganic magnetic composite resins was established. The procedure was based upon immobilization of magnetite (Mag) as a ferromagnetic material within the polymer poly(acrylic acid acrylonitrile) P(AA-AN) and the ion exchange resin (Amberlite IR120). The produced magnetic resins, IR120-PAN-Mag (RI) and P(AA-AN)-Mag (R2) were assessed as sorbents for Cr(VI). Various factors influencing the sorption of Cr(VI), e.g., pH, equilibrium time, initial concentration and temperature were studied. The sorption process was very fast initially and maximum sorption was achieved within 3 h and pH 5.1. The kinetic of the system has been evaluated with pseudo first order model, second order model, Elovich model, intra-particle diffusion model and liquid film diffusion model. Chromium interaction with composite particles followed second-order kinetics with a correlation coefficient extremely high and closer to unity and rate constant (k(s)) has the values 1.6810^-4 and 1.910^-4 g (mg^-1 min^-1) for RI and R², respectively. The values of equilibrium sorption capacity (q(e)) are consistent with the modeled data and attain the range 893-951 mg g^-1. Kinetically, both pore diffusion and film diffusion are participating in ruling the diffusion of Cr(VI) ions. The sorption data gave good fits with Temkin and Flory-Huggins isotherm models. The isotherm parameters related to the heat of sorption are in the range 8-16 kJ mol^-1 which is the range of bonding energy for ion exchange interactions and so suggest an ion exchange mechanism for removal of Cr(VI) by the composite sorbents. The adsorption process was exothermic with H in the range of -73 to -97 kJ mol^-1. The negative values of Gibbs free energy confirm the feasibility and the spontaneous nature of Cr(VI) removal with these novel composites. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Acrylonitrile, Activated Carbon, Adsorption, Adsorption Process, Aqueous Solutions, Bonding, Capacity, Characteristics, Chromium, Cobalt, Composite, Composite Particles, Composites, Concentration, Copper(II), Correlation, Correlation Coefficient, Cr(VI), Cr(VI), Cr(VI) Removal, Data, Diffusion, Diffusion Model, Elovich, Elovich Model, Energy, Equilibrium, Equilibrium Time, Exchange, Exothermic, Factors, Feasibility, Ferromagnetic Composites, Film, Film Diffusion, First, First Order, Gibbs Free Energy, Immobilization, Inorganic Ion-Exchangers, Interaction, Interactions, Intra-Particle Diffusion, Intraparticle, Intraparticle Diffusion, Intraparticle Diffusion Model, Ion Exchange, Ion Exchange Resin, Ion-Exchange, Ions, Isotherm, Isotherm Models, Isotherm Parameters, Kinetic, Kinetics, Liquid, Magnetic, Magnetic Composite, Magnetic Resins, Magnetite, Mechanism, Metal, Metal Removal, Model, Models, Particles, pH, Phosphate, Polymer, Pore Diffusion, Procedure, Process, Pseudo, Pseudo First Order, Pseudo-First-Order, Rate Constant, Removal, Resin, Resins, Rights, Second Order, Second Order Kinetics, Second-Order, Second-Order Kinetics, Solutions, Sorbents, Sorption, Sorption, Sorption Capacity, Sorption Process, Spontaneous, Synthesis, Temperature, Time, Values, Waste-Water, X

? Pokhrel, D. and Viraraghavan, T. (2008), Arsenic removal from an aqueous solution by modified A. niger biomass: Batch kinetic and isotherm studies. Journal of Hazardous Materials,