Personal Research Database

Full Text: 2008\J Haz Mat152, 263.pdf

Abstract: The use of a new activated carbon developed from date palm seed wastes, generated in the jam industry, for removing toxic chromium from aqueous solution has been investigated. The activated carbon has been achieved from date palm seed by dehydrating methods using concentrated sulfuric acid. The batch experiments were conducted to determine the adsorption capacity of the biomass. The effect of initial metal concentration (25-125 mg l^-1), pH, contact time, and concentration of date palm seed carbon have been studied at room temperature. A strong dependence of the adsorption capacity on pH was observed, the capacity increase as pH value decrease and the optimum pH value is pH 1.0. Kinetics and adsorption equilibrium were studied at different sorbent doses. The adsorption process was fast and the equilibrium was reached within 180 min. The maximum removal was 100% for 75 mg l^-1 of Cr⁶⁺, concentration on 4 g l^-1 carbon concentration and the maximum adsorption capacity was 120.48 mg g^-1. The kinetic data were analyzed using various kinetic models - pseudo-first order equation, pseudo-second order equation, Elovich equation and intraparticle, diffusion equation - and the equilibrium data were tested using several isotherm models, Langmuir, Freundlich, Koble-Corrigan, Redlich-Peterson, Tempkin, Dubinin-Radushkevich and Generalized isotherm equations. The Elovich equation and pseudo-second order equation provide the greatest accuracy for the kinetic data and Koble-Corrigan and Langmuir models the closest fit for the equilibrium data. Activation energy of sorption has also been evaluated as 0.115 and 0.229 kJ mol^-1. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Activation, Activation Energy, Adsorption, Adsorption, Adsorption Equilibrium, Alga Ulva-Lactuca, Aqueous Solution, Aqueous-Solution, Biomass, Biosorption, Capacity, Carbon, Chromium, Date Palm Seed, Diffusion, Elovich Equation, Equilibrium, Experiments, Freundlich, Isotherm, Isotherm Equations, Kinetic, Kinetic Models, Kinetics, Kinetics, Langmuir, Mass-Transfer, Metal, Methods, Methylene-Blue, Models, pH, Pseudo-Second Order, Removal, Rights, Room Temperature, Sludge PWS, Solution, Sorption, Temperature, Toxic Chromium, Treatment, Wastewater

? Ponnusami, V., Vikram, S. and Srivastava, S.N. (2008), Guava (Psidium guaiava) leaf powder: Novel adsorbent for removal of Methylene blue from aqueous solutions. Journal of Hazardous Materials, 152 (1), 276-286.

Full Text: 2008\J Haz Mat152, 276.pdf

Abstract: Batch sorption experiments were carried out using a novel adsorbent, guava leaf powder (GLP), for the removal of methylene blue (MB) from aqueous solutions. Potential of GLP for adsorption of MB from aqueous solution was found to be excellent. Effects of process parameters pH, adsorbent dosage, concentration, particle size and temperature were studied. Temperature-concentration interaction effect on dye uptake was studied and a quadratic model was proposed to predict dye uptake in terms of concentration, time and temperature. The model conforms closely to the experimental data. The model was used to find optimum temperature and concentration that result in maximum dye uptake. Langmuir model represent the experimental data well. Maximum dye uptake was found to be 295 mg/g, indicating that GLP can be used as an excellent low-cost adsorbent. Pseudo-first-order, pseudo-second order and intraparticle diffusion models were tested. From experimental data it was found that adsorption of MB onto GLP follow pseudo second order kinetics. External diffusion and intraparticle diffusion play roles in adsorption process. Free energy of adsorption (G), enthalpy change (H) and entropy change (S) were calculated to predict the nature of adsorption. Adsorption in packed bed was also evaluated. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorption, Aqueous, Aqueous Solutions, Bagasse Fly-Ash, Basic Dye, Batch Adsorption, Biosorption, Diffusion, Dye, Dye Removal, Dye Removal, Dye Uptake, Elsevier, Entropy, Equilibrium, Fixed Bed Adsorption, Guava Leaf Powder, Interaction, Intraparticle Diffusion, Kinetics, Langmuir, Langmuir Model, Methylene Blue, Model, Models, Particle Size, pH, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-Second Order, Pseudo-Second-Order, Removal, Second Order, Solutions, Sorption, Temperature, Thermodynamics

? Sarı, A. and Tüzen, M. (2008), Biosorption of Pb(II) and Cd(II) from aqueous solution using green alga (Ulva lactuca) biomass. Journal of Hazardous Materials, 152 (1), 302-308.

Full Text: 2008\J Haz Mat152, 302.pdf

Abstract: The biosorption characteristics of Pb(II) and Cd(II) ions from aqueous solution using the green alga (Ulva lactuca) biomass were investigated as a function of pH, biomass dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of the metal ions by U. lactuca biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The monolayer biosorption capacity of U. lactuca biomass for Pb(II) and Cd(II) ions was foundtobe 34.7 mg/g and 29.2 mg/g, respectively. From the D-R isotherm model, the mean free energy was calculated as 10.4 kJ/mol for Pb(II) biosorption and 9.6 kJ/mol for Cd(II) biosorption, indicating that the biosorption of both metal ions was taken place by chemisorption. The calculated thermodynamic parameters (G, H and S) showed that the biosorption of Pb(H) and Cd(II) ions onto U. lactuca biomass was feasible, spontaneous and exothermic under examined conditions. Experimental data were also tested in terms of biosorption kinetics using pseudo-first-order and pseudo-second-order kinetic models. The results showed that the biosorption processes of both metal ions followed well pseudo-second-order kinetics. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Aqueous Solution, Biomass, Biosorption, Biosorption Characteristics, Biosorption Kinetics, Cadmium, Cadmium(II), Capacity, Cd(II), Equilibrium, Freundlich, Freundlich Isotherm, Function, Green Alga, Ions, Isotherm, Kinetic, Kinetic Models, Kinetics, Langmuir, Lead(II), Lead(II), Marine-Algae, Metal, Metal Ions, Metals, Model, Models, Monolayer, Ni(II), Pb(II), pH, Pseudo-Second-Order Kinetics, Removal, Rights, Solution, Sorption, Temperature, Thermodynamic Parameters, Thermodynamics, Ulva Lactuca

? King, P., Anuradha, K., Lahari, S.B., Kumar, Y.P. and Prasad, V.S.R.K. (2008), Biosorption of zinc from aqueous solution using Azadirachta indica bark: Equilibrium and kinetic studies. Journal of Hazardous Materials, 152 (1), 324-329.

Full Text: 2008\J Haz Mat152, 324.pdf

Abstract: The removal of zinc ions from aqueous solutions on the biomass of Azadirachta indica bark has been studied by using batch adsorption technique. The biosorption studies were determined as a function of contact time, pH, initial metal ion concentration, average biosorbent size and biosorbent dosage. The equilibrium metal uptake was increased and percentage biosorption was decreased with an increase in the initial concentration and particle size of biosorbent. The maximum zinc biosorption occurred at pH 6 and percentage biosorption increases with increase in the biosorbent dosage. Experimental data obtained were tested with the adsorption models like Langmuir, Freundlich and Redlich-Peterson isotherms. Biosorption isothermal data were well interpreted by Langmuir model with maximum biosorption capacity of 33.49 mg/g of zinc ions on A. indica bark biomass and kinetic data were properly fitted with the pseudo-second-order kinetic model. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Aqueous Solution, Aqueous Solutions, Azadirachta Indica Bark, Batch Adsorption, Biomass, Biosorbent, Biosorption, Capacity, Equilibrium, Freundlich, Function, Heavy-Metals, Ions, Isotherms, Kinetic, Kinetic Studies, Langmuir, Metal, Metal Uptake, Model, Models, Particle Size, pH, Removal, Rights, Size, Solution, Sorption, Waste, Zinc, Zn(II)

? Annadurai, G., Ling, L.Y. and Lee, J.F. (2008), Adsorption of reactive dye from an aqueous solution by chitosan: Isotherm, kinetic and thermodynamic analysis. Journal of Hazardous Materials, 152 (1), 337-346.

Full Text: 2008\J Haz Mat152, 337.pdf

Abstract: The adsorption of Remazol black 13 (Reactive) dye onto chitosan in aqueous solutions was investigated. Experiments were carried out as function of contact time, initial dye concentration (100-300mg/L), particle size (0.177, 0.384, 1.651 mm), pH (6.7-9.0), and temperature (30-60C. The equilibrium adsorption data of reactive dye on chitosan were analyzed by Langmuir and Freundlich models. The maximum adsorption capacity (q(m)) has been found to be 91.47-130.0 mg/g. The amino group nature of the chitosan provided reasonable dye removal capability. The kinetics of reactive dye adsorption nicely followed the pseudo-first and second-order rate expression which demonstrates that intraparticle diffusion plays a significant role in the adsorption mechanism. Isotherms have also been used to obtain the thermodynamic parameters such as free energy, enthalpy and entropy of adsorption. The positive value of the enthalpy change (0.212 kJ/mol) indicated that the adsorption is endothermic process. The results indicate that chitosan is suitable as adsorbent material for adsorption of reactive dye form aqueous solutions. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Acid Dye, Activated Carbon, Adsorbent, Adsorption, Analysis, Aqueous Solution, Aqueous Solutions, Basic Dye, Capacity, Chitin, Chitosan, Diffusion, Dye, Dye Removal, Entropy, Equilibrium, Expression, Freundlich, Function, Isotherm, Isotherms, Kinetic, Kinetic Study, Kinetics, Langmuir, Mechanism, Models, Particle Size, pH, Pore Diffusion, Reactive Dye, Removal, Rice Husk, Rights, Size, Solution, Sorption, Temperature, Thermodynamic Parameters, Waste-Water

? Hasan, S.H., Singh, K.K., Prakash, O., Talat, M. and Ho, Y.S. (2008), Removal of Cr(VI) from aqueous solutions using agricultural waste ‘maize bran’. Journal of Hazardous Materials, 152 (1), 356-365.

Full Text: 2008\J Haz Mat-Hasan.pdf; 2008\J Haz Mat152, 356.pdf

Abstract: Novel biosorbent ‘maize bran’ has been successfully utilized for the removal of Cr(VI) from aqueous solution. The effect of different parameters such as contact time, sorbate concentration, pH of the medium and temperature were investigated and maximum uptake of Cr(VI) was 312.52 (mg g^-1) at pH 2.0, initial Cr(VI) concentration of 200mg L^-1 and temperature of 40C. Effect of pH showed that maize bran was not only removing Cr(VI) from aqueous solution but also reducing toxic Cr(VI) into less toxic Cr(III). The sorption kinetics was tested with first order reversible, pseudo-first order and pseudo-second order reaction and it was found that Cr(VI) uptake process followed the pseudo-second order rate expression. Mass transfer of Cr(VI) from bulk to the solid phase (maize bran) was studied at different temperatures. Different thermodynamic parameters, viz., G, H and S have also been evaluated and it has been found that the sorption was feasible, spontaneous and endothermic in nature. The Langmuir and Freundlich equations for describing sorption equilibrium were applied and it was found that the process was well described by Langmuir isotherm. Desorption studies was also carried out and found that complete desorption of Cr(VI) took place at pH of 9.5. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Agricultural, Agricultural Waste, Aqueous Solution, Aqueous Solutions, Biosorbent, Chromium(VI), Concentration, Cr(III), Cr(VI), Desorption, Endothermic, Equilibrium, Expression, First, First Order, Freundlich, Isotherm, Kinetics, Langmuir, Langmuir Isotherm, Maize Bran, Mass Transfer, pH, Pseudo First Order, Pseudo Second Order, Pseudo-First Order, Pseudo-First Order and Pseudo-Second Order, Pseudo-First-Order, Pseudo-Second Order, Pseudo-Second-Order, Removal, Solution, Solutions, Sorbate, Sorption, Sorption Isotherms, Sorption Kinetics, Temperature, Thermodynamic, Thermodynamic Parameters, Uptake, Waste

? Borba, C.E., da Silva, E.A., Fagundes-Klen, M.R., Kroumov, A.D. and Guirardello, R. (2008), Prediction of the copper(II) ions dynamic removal from a medium by using mathematical models with analytical solution. Journal of Hazardous Materials, 152 (1), 366-372.

Full Text: 2008\J Haz Mat152, 366.pdf

Abstract: A copper(II) ions biosorption by Sargassum sp. biomass was studied in a fixed bed column at 30°C and pH 3.5. The experimental curves were obtained for the following feed concentrations -2.08, 4.16, 6.42 and 12.72 mmol/L of the copper ions. The mathematical models developed by Thomas and Bohart-Adams were used for description of ions sorption process in the column. The models principle hypothesis is that the mass transfer controlling stage of the process is the adsorption kinetics between sorbate and adsorbent. The phenomena such as intraparticle diffusion, a mass transfer external resistance and axial dispersion effects were out of considerations. Some of the models parameters were experimentally determined (rho(B), epsilon, u(0), C-0) and the others were evaluated on the bases of the experimental data (k(a1), k(a2)). The unique fitting parameter in all models was the adsorption kinetic constant. The identification procedure was based on the least square statistical method. Simulation results show that the models describe well a copper ions sorption process in a fixed bed column. The used models can be considered as useful tools for adsorption process design and optimization in fixed bed column by using algae biomass of Sargassum sp. as an adsorbent. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Aqueous-Solution, Behavior, Biomass, Biosorption, Bohart-Adams, Breakthrough Curve, Breakthrough Curves, Cadmium, Chaff, Fixed Bed, Fixed-Bed Column, Kinetics, Lead(II), Process Design, Sorption, Thomas

? Behnajady, M.A., Modirshahla, N., Tabrizi, S.B. and Molanee, S. (2008), Ultrasonic degradation of Rhodamine B in aqueous solution: Influence of operational parameters. Journal of Hazardous Materials, 152 (1), 381-386.

Full Text: 2008\J Haz Mat152, 381.pdf

Abstract: The aim of the study was to investigate decolorization of Rhodamine B (RB) in aqueous solution using ultrasonic degradation. The results showed that decolorization follows pseudo-first-order reaction kinetics. The apparent reaction rate constant (kap) was found to increase with decreasing pH and decreases with increasing initial RB concentration. Power density was very important parameter and increasing it causes a considerable increase of removal efficiency. UV-vis spectral changes of RB indicate that in the sonolysis of RB, the cleavage of aromatic chromophore ring structure and the N-deethylation take place, but decomposition of aromatic structure is predominant.

Keywords: Aqueous Solution, Changes, Cleavage, Concentration, Decolorization, Decomposition, Degradation, Degradation Mechanism, Efficiency, Kinetics, pH, Pseudo First Order, Pseudo-First-Order, Rate Constant, Reaction Kinetics, Removal, Removal Efficiency, Rhodamine B, Rhodamine-B, Solution, Sonication, Structure, Ultrasonic, Ultrasonic Bath, Ultrasonic Decolorization

? Gupta, V.K. and Rastogi, A. (2008), Biosorption of lead from aqueous solutions by green algae Spirogyra species: Kinetics and equilibrium studies. Journal of Hazardous Materials, 152 (1), 407-414.

Full Text: 2008\J Haz Mat152, 407.pdf

Abstract: Biosorption is the effective method for the removal of heavy metal ions from wastewaters. Results are presented showing the sorption of Pb(II) from solutions by biomass of commonly available, filamentous green algae Spirogyra sp. Batch experiments were conducted to determine the biosorption properties of the biomass and it was observed that the maximum adsorption capacity of Pb(II) ion was around 140 mg metal/g of biomass at pH 5.0 in 100 min with 200 mg/L of initial concentration. Temperature change in the range 20-40C affected the adsorption capacity and the nature of the reaction was found to be endothermic in nature. Uptake kinetics follows the pseudo- second-order model and equilibrium is well described by Langmuir isotherm. Isotherms have been used to determine thermodynamic parameters of the process, viz., free energy change, enthalpy change and entropy change. Various properties of the algae, as adsorbent, explored in the characterization part were chemical composition of the adsorbent, thermal analysis by TGA, surface area calculation by BET method, surface morphology with scanning electron microscope images and surface functionality by FTIR. FTIR analysis of algal biomass revealed the presence of amino, carboxyl, hydroxyl and carbonyl groups, which are responsible for biosorption of metal ions. The results indicated that the biomass of Spirogyra sp. is an efficient biosorbent for the removal of Pb(II) from aqueous solutions. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Analysis, Aqueous Solutions, BET, Biomass, Biosorbent, Biosorption, Cadmium, Capacity, Characterization, Chromium(VI), Copper, Entropy, Equilibrium, Experiments, FTIR, Green Algae, Heavy Metal, Heavy Metal Ions, Heavy-Metal Biosorption, Ions, Isotherm, Isotherms, Kinetics, Langmuir, Langmuir Isotherm, Langmuir Model, Lead, Marine-Algae, Metal, Metal Ions, Microalgae, Model, Morphology, Pb(II), pH, Removal, Rights, Sorption, Spirogyra sp., Surface Area, Thermodynamic Parameters, Water

? Reijnders, L. (2008), Hazard reduction for the application of titania nanoparticles in environmental technology. Journal of Hazardous Materials, 152 (1), 440-445.

Full Text: 2008\J Haz Mat152, 440.pdf

Abstract: Photocatalytically active titania (TiO₂) nanoparticles are applied, and considered for application, in the degradation of hazardous substances. However, these nanoparticles are also hazardous by themselves. High efficiency immobilization of TiO₂ nanoparticles on large inorganic supports that are not vulnerable to photocatalytic degradation is conducive to hazard reduction. Immobilization should also aim at minimizing the release of TiO₂ nanoparticles from such supports due to attrition. In doing so there may be a trade off between hazard and photocatalytic activity.

Keywords: Application, Degradation, Efficiency, Environmental, Environmental Technology, Hazard, Hazard Reduction, Immobilization, Nanoparticles, Photocatalytic, Photocatalytic Activity, Photocatalytic Degradation, Reduction, Release, Technology, TiO₂, TiO₂ Nanoparticles, Titania, Trade Off

? Eseudero, C., Gabaldon, C., Marzal, P. and Villaescusa, I. (2008), Effect of EDTA on divalent metal adsorption onto grape stalk and exhausted coffee wastes. Journal of Hazardous Materials, 152 (2), 476-485.

Full Text: 2008\J Haz Mat152, 476.pdf

Abstract: In the present work, two industrial vegetable wastes, grape stalk, coming from a wine producer, and exhausted coffee, coming from a soluble coffee manufacturer, have been investigated for the removal of Cu(II) and Ni(II) from aqueous solutions in presence and in absence of the strongly complexing agent EDTA. Effects of pH and metal-EDTA molar ratio, kinetics as a function of sorbent concentration, and sorption equilibrium for both metals onto both sorbents were evaluated in batch experiments. Metal uptake was dependent of pH, reaching a maximum from pH around 5.5. EDTA was found to dramatically reduce metal adsorption, reaching total uptake inhibition for both metals onto both sorbents at equimolar metal:ligand concentrations. Kinetic results were successfully modelled by means of the pseudo second order model. Langmuir and Freundlich models were used to describe the sorption equilibrium data. Grape stalk showed the best performance for Cu(II) and Ni(II) removal in presence and in absence of EDTA, despite exhausted coffee appears as less sensitive to the presence of complexing agent. The performance of Cu(H) and Ni(II) sorption onto grape stalk in a continuous flow process was evaluated. In solutions containing EDTA, an initial metal concentration in the outlet flow corresponding to the complexed metal fraction was observed from the beginning of the process. A high metal recovery yield (> 97%) was achieved by feeding the metal-loaded column with 0.05 M HCl. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Aqueous Solutions, Aqueous-Solutions, Batch, Batch and Column Studies, Batch Experiments, Biosorption, Column, Complexing Agent, Concentration, Copper Removal, Cu(II), Data, Date Pits, EDTA, Equilibrium, Exhausted Coffee, Experiments, Feeding, Flow, Fly-Ash, Freundlich, Function, Granular Activated Carbon, Grape Stalk, Heavy Metals, Heavy-Metals, Industrial, Inhibition, Ions, Kinetic, Kinetics, Langmuir, Metal, Metal Adsorption, Metal Recovery, Metals, Model, Models, Ni(II), Performance, pH, Presence, Process, Pseudo, Pseudo Second Order, Pseudo-Second-Order, Recovery, Red Mud, Removal, Rights, Second Order, Second-Order, Solutions, Sorbent, Sorbents, Sorption, Uptake, Vegetable, Water, Work

? Krishnan, K.A. and Haridas, A. (2008), Removal of phosphate from aqueous solutions and sewage using natural and surface modified coir pith. Journal of Hazardous Materials, 152 (2), 527-535.

Full Text: 2008\J Haz Mat152, 527.pdf

Abstract: Iron impregnated coir pith (CP-Fe-I) can be effectively used for the removal of phosphate from aqueous streams and sewage. Iron impregnation on natural coir pith was carried out by drop by drop addition method. The effect of various factors such as pH, initial concentration of phosphate, contact time and adsorbent dose on phosphate adsorption was studied by batch technique. The pH at 3.0 favored the maximum adsorption of phosphate from aqueous solutions. The effect of pH on phosphate adsorption was explained by pH on phosphate speciation in solution and affinity of anions towards the adsorbent sites. A comparative study of the adsorption of phosphate using CP-Fe-I and CP (coir pith) was made and results show that the former one is five to six times more effective than the latter. Kinetic studies revealed that the adsorption process followed a pseudo-second order kinetic model. Adsorption followed Langmuir isotherm model. Column studies were conducted to examine the utility of the investigated adsorbent for the removal of phosphate front continuously flowing aqueous solutions. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorbent Dose, Adsorption, Aqueous Solutions, Batch, Coir Pith, Column, Comparative Study, Concentration, Impregnation, Iron, Iron Impregnated Coir Pith, Isotherm, Isotherm Model, Kinetic, Kinetic Model, Kinetic Studies, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Model, Modified, pH, Phosphate, Phosphate Adsorption, Phosphate Removal, Pith, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second-Order, Removal, Sewage, Solution, Solutions, Speciation, Streams, Surface, Utility

? Kumar, A., Prasad, B. and Mishra, I.M. (2008), Adsorptive removal of acrylonitrile by commercial grade activated carbon: Kinetics, equilibrium and thermodynamics. Journal of Hazardous Materials, 152 (2), 589-600.

Full Text: 2008\J Haz Mat152, 589.pdf

Abstract: The potential of activated carbons-powdered (PAC) and granular (GAC), for the adsorption of acrylonitrile (AN) at different initial AN concentrations (50 < CO < 500 mg/l) from aqueous solutions was studied over the temperature range of 303-333 K. The effect of adsorbent dosage, initial AN concentration, contact time, and the change in pH with addition of adsorbents on adsorption was studied. The Langmuir, Freundlich, Tempkin, and Redlich-Peterson (R-P) isotherm equations were used to test their fit with the experimental data, and the model parameters were determined for different temperatures. The Langirmir and R-P models were found to be the best to describe the equilibrium isotherm data of AN adsorption on PAC and GAC, respectively. Error analysis also confirmed the efficacy of the R-P isotherm to best fit the experimental data. The pseudo-second order kinetic model best represents the kinetics of the adsorption of AN onto PAC and GAC. Maximum adsorption capacity of PAC and GAC at optimum conditions of AN removal (adsorbent dose approximate to 20 g/l of solution, and equilibrium time approximate to 5 h) was found to be 51.72 and 46.63 mg/g, respectively. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Acrylonitrile, Activated carbon, adsorbent, adsorbents, Adsorption, adsorption capacity, analysis, aqueous solutions, capacity, carbon, concentration, data, efficacy, equilibrium, equilibrium isotherm, Error analysis, experimental, Freundlich, GAC, isotherm, isotherm equations, Isotherms, kinetic, kinetic model, Kinetics, Langmuir, model, models, PAC, pH, potential, pseudo second order, pseudo-second order, pseudo-second-order, Redlich-Peterson, removal, solution, solutions, temperature, Thermodynamics

? Isa, M.H., Ibrahim, N., Aziz, H.A., Adlan, M.N., Sabiani, N.H.M., Zinatizadeh, A.A.L. and Kutty, S.R.M. (2008), Removal of chromium(VI) from aqueous solution using treated oil palm fibre. Journal of Hazardous Materials,