Personal Research Database

Full Text: 2008\J Haz Mat152, 1073.pdf

Abstract: The objective of this work was to propose an altemative use for coffee husks (CH), a coffee processing residue, as untreated sorbents for the removal of heavy metal ions from aqueous solutions. Biosorption studies were conducted in a batch system as a function of contact time, initial metal ion concentration, biosorbent concentration and pH of the solution. A contact time of 72 It assured attainment of equilibrium for Cu(II), Cd(II) and Zn(II). The sorption efficiency after equilibrium was higher for Cu(II) (89-98% adsorption), followed by Cd(II) (65-85%) and Zn(II) (48-79%). Even though equilibrium was not attained in the case of Cr(VI) ions, sorption efficiency ranged from 79 to 86%. Sorption performance improved as metal ions concentrations were lowered. The experimental sorption equilibrium data were fitted by both Langmuir and Freundlich sorption models, with Langmuir providing the best fit (R-2 > 0.95). The biosorption kinetics was determined by fitting first and second-order kinetic models to the experimental data, being better described by the pseudo-second-order model (R-2 > 0.99). The amount of metal ions sorbed increased with the biosorbent concentration in the case of Cu(H) and Cr(VI) and did not present significant variations for the other metal ions. The effect of the initial pH in the biosorption efficiency was verified in the pH range of 4-7, and the results showed that the highest adsorption capacity occurred at distinct pH values for each metal ion. A comparison of the maximum sorption capacity of several untreated biomaterial-based residues showed that coffee husks are suitable candidates for use as biosorbents in the removal of heavy metals from aqueous solutions. (C) 2007 Elsevier B.V All rights reserved.

Keywords: Adsorption, Adsorption Capacity, Agricultural Waste, Alternative, Aqueous Solutions, Batch, Batch System, Biosorbent, Biosorbents, Biosorption, Biosorption Kinetics, Capacity, Cd(II), Comparison, Concentration, Cr(VI), Cu(II), Data, Efficiency, Equilibrium, Experimental, First, Freundlich, Function, Heavy Metal, Heavy Metal Ions, Heavy Metals, Kinetic, Kinetic Models, Kinetics, Langmuir, Metal, Metal Ions, Metals, Model, Models, Performance, pH, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Removal, Second Order, Second-Order, Solution, Solutions, Sorbents, Sorption, Sorption Capacity, Sorption Models, Sorption Performance, Toxic Pollutants, Work, Zn(II)

? Lv, L.A., Wang, W., Wei, M. and Cheng, H.J. (2008), Bromide ion removal from contaminated water by calcined and uncalcined MgAl-CO₃ layered double hydroxides. Journal of Hazardous Materials, 152 (3), 1130-1137.

Full Text: 2008\J Haz Mat152, 1130.pdf

Abstract: A fundamental investigation on the uptake of bromide ion from contaminated water by calcined and uncalcined MgAl-CO₃ layered double hydroxides (LDHs) were conducted in batch mode. The uptake capacity of calcined LDHs (CLDH) is higher than that of uncalcined LDHs, due to their different mechanisms which are confirmed by powder X-ray diffraction, FT-IR spectroscopy and TG-MS measurements. The former mechanism is based on the reconstruction of CLDH to Br-LDHs, whilst the latter is related to the surface adsorption. It has been found that the LDHs calcined at 500C with Mg/Al molar ratio of 4 represents the highest capacity to remove bromide ion from aqueous solution. The equilibrium isotherms of uptake of bromide by CLDH were well fitted by the Langmuir equation, and thermodynamic parameters such as G, H and S were calculated from Langmuir constants. The negative value of H confirms the exothermic nature of adsorption. Three kinetics models were used to fit the kinetics experimental data, and it was found that the pseudo-second order kinetics model could be used to describe the uptake process appropriately. The value of Ea was calculated to be 79.9 kJ/mol, which suggests that the process of uptake bromide is controlled by the reaction rate of bromide with the CLDH rather than diffusion. (c) 2007 Elsevicr B.V. All rights reserved.

Keywords: Adsorption, Aqueous Solution, Batch, Batch Mode, Bromide, Calcined, Capacity, Data, Diffusion, Equilibrium, Exothermic, Experimental, FT-IR, FTIR, Investigation, Isotherms, Kinetics, Kinetics Model, Kinetics Models, Langmuir, Langmuir Equation, Layered Double Hydroxides, Mechanism, Mechanisms, Mode, Model, Models, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-Second Order, Pseudo-Second Order Kinetics, Pseudo-Second-Order, Removal, Solution, Spectroscopy, Surface, Thermodynamic, Thermodynamic Parameters, Uptake, Value, Water, X-Ray, X-Ray Diffraction

? Jang, S.H., Min, B.G., Jeong, Y.G., Lyoo, W.S. and Lee, S.C. (2008), Removal of lead ions in aqueous solution by hydroxyapatite/polyurethane composite foams. Journal of Hazardous Materials, 152 (3), 1285-1292.

Full Text: 2008\J Haz Mat152, 1285.pdf

Abstract: We have prepared hydroxyapatite/polyurehthane (HAp/PU) composite foams with two different HAp contents of 20 and 50 wt.% and investigated their removal capability of Pb²⁺ ions from aqueous solutions with various initial Pb²⁺ ion concentrations and pH values of 2-6. HAp/PU composite foams synthesized exhibited well-developed open pore structures which provide paths for the aqueous solution and adsorption sites for Pb²⁺ ions. With increasing the HAp content in the composites, the removal capability of Pb²⁺ ions by the composite foams increases owing to the higher adsorption capacity, whereas the removal rate is slower due to the less uniform dispersity of HAp in composite foams. The removal rate of Pb²⁺ ions is also slower with increasing the initial Pb²⁺ ion concentration in aqueous solutions. The removal mechanism of Pb²⁺ ion by the composites is varied, depending on the pH value of aqueous solution: the dissolution of HAp and precipitation of hydroypyromorphite is dominant at lower pH 2-3, the adsorption of Pb²⁺ ions on the HAp/PU composite surface and ion exchange reaction between Ca²⁺ of HAp and Pb²⁺ in aqueous solution is dominant at higher pH 5-6, and two removal mechanisms compete at pH 4. The equilibrium removal process of Pb²⁺ ions by the HAp/PU composite foam at pH 5 was described well with the Langmuir isotherm model, resulting in the maximum adsorption capacity of 150 mg/g for the composite foam with 50 wt.% HAp content. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Composite Foam, Heavy Metals, Hydroxyapatite, Polyurethane, Heavy-Metal Ions, Synthetic Hydroxyapatite, Waste-Water, Immobilization, Phosphate, Pb(II)

? Ucun, H., Bayhan, Y.K. and Kaya, Y. (2008), Kinetic and thermodynamic studies of the biosorption of Cr(VI) by Pinus sylvestris Linn. Journal of Hazardous Materials, 153 (1-2), 52-59.

Full Text: 2008\J Haz Mat153, 52.pdf

Abstract: Biosorption equilibrium, kinetics and thermodynamics of chromium(VI) ions onto cone biomass were studied in a batch system with respect to temperature and initial metal ion concentration. The biosorption efficiency of chromium ions to the cone biomass decreased as the initial concentration of metal ions was increased. But cone biomass of Pinus sylvestris Linn. exhibited the highest Cr(VI) uptake capacity at 45C. The biosorption efficiency increased from 67% to 84% with an increase in temperature from 25 to 45C at an initial Cr(VI) concentration of 300 mg/L. The Langnmir isotherm model was applied to experimental equilibrium data of Cr(VI) biosorption depending on temperature. According to Langnmir isotherm, the monolayer saturation capacity (Q(max)) is 238.10 mg/g. The pseudo-first-order and pseudo-second-order kinetic models were applied to test the experimental data for initial Cr(VI). The pseudo-second-order kinetic model provided the best correlation of the used experimental data compared to the pseudo-first-order kinetic model. The activation energy of biosorption (E-a) was determined as 41.74 kJ/mol using the Arrhenius equation. Using the thermodynamic equilibrium coefficients obtained at different temperatures, the thermodynamic constants of biosorption (G, H and S) were also evaluated. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activation, Activation Energy, Batch, Batch System, Biomass, Biosorption, Capacity, Chromium, Chromium(VI), Concentration, Correlation, Cr(VI), Data, Efficiency, Energy, Equilibrium, Experimental, Isotherm, Isotherm Model, Kinetic, Kinetic Model, Kinetic Models, Kinetics, Kinetics and Thermodynamics, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Metal, Metal Ions, Model, Models, Monolayer, Pinus Sylvestris, Pinus Sylvestris Linn., Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Saturation, Temperature, Thermodynamic, Thermodynamic Studies, Thermodynamics, Uptake

? Wang, X.N., Zhu, N.W. and Yin, B.K. (2008), Preparation of sludge-based activated carbon and its application in dye wastewater treatment. Journal of Hazardous Materials, 153 (1-2), 22-27.

Full Text: 2008\J Haz Mat153, 22.pdf

Abstract: A novel activation process was adopted to produce highly porous activated carbon from cyclic activated sludge in secondary precipitator in municipal wastewater treatment plant for dye removal from colored wastewater. The physical properties of activated carbon produced with the activation of 3 M KOH solution in the atmosphere of steam were investigated. Adsorption removal of a dye, Acid Brilliant Scarlet GR, from aqueous solution onto the sludge-based activated carbon was studied under varying conditions of adsorption time, initial concentration, carbon dosage and pH. Adsorption equilibrium was obtained in 15 min for the dye initial concentration of 300 mg/L. Initial pH of solution had an insignificant impact on the dye removal. Results indicated that 99.7% coloration and 99.6% total organic carbon (TOC) were removed after 15 min adsorption in the synthetic solution of Acid Brilliant Scarlet GR with initial concentration of 300 mg/L of the dye and 20 g/L activated carbon. The Langmuir and Freundlich equilibrium isotherm models fitted the adsorption data well with R-2 = 0.996 and 0.912, respectively. Accordingly, it is concluded that the procedure of developing activated carbon used in this study could be effective and practical for utilizing in dye wastewater treatment. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Activated Sludge, Adsorption, Acid Brilliant Scarlet GR, Sewage-Sludge, Aqueous-Solutions, Physical Activation, Chemical Activation, Removal

? Selvakumar, R., Kavitha, S., Sathishkumar, M. and Swaminathan, K. (2008), Arsenic adsorption by polyvinyl pyrrolidone K25 coated cassava peel carbon from aqueous solution. Journal of Hazardous Materials, 153 (1-2), 67-74.

Full Text: 2008\J Haz Mat153, 67.pdf

Abstract: Sorption of arsenic from aqueous solution was carried out using polyvinyl pyrrolidone K25 coated cassava peel carbon (PVPCC). Batch experiments were conducted to determine the effect of contact time, initial concentration, pH and desorption. Batch sorption data’s were fitted to Lagergren kinetic studies. Column studies were also conducted using PVPCC as adsorbent. The optimized flow rate of 2.5 mL min^-1 and bed height 10 cm were used to determine the effect of metal ion concentration on removal of As(V). BDST model was applied to calculate the adsorption capacity (N-0) of column. The N-0 value of 2.5910^-5, 4.2110^-5, 4.0510^-5, 4.2610^-5 and 3.210^-5 Mg g^-1 were obtained for 0.5, 1.0, 1.5, 2.0 and 2.5 mg L^-1 of As(V), respectively. The batch sorption proved to be more efficient than the column sorption. The sorption of As(V) and the nature of the adsorbent was examined by Fourier transmission infrared spectroscopy (FTIR) and X-ray diffraction (XRD) studies, respectively. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: PVPK25, As(V), Cassava Carbon, Xrd, FTIR Studies, Coir Pith Carbon, Hydrous Iron-Oxide, Drinking-Water, Fungal Biomass, Husk Carbon, Removal, As(V), Waste, Sorption, As(III)

? Crini, G., Gimbert, F., Robert, C., Martel, B., Adam, O., Morin-Crini, N., De Giorgi, F. and Badot, P.M. (2008), The removal of Basic Blue 3 from aqueous solutions by chitosan-based adsorbent: Batch studies. Journal of Hazardous Materials, 153 (1-2), 96-106.

Full Text: 2008\J Haz Mat153, 96.pdf

Abstract: Chitosan-based adsorbent (CHITOD material) is used for the removal of Basic Blue 3 (BB 3) from aqueous solutions. The adsorption of BB 3 on CHITOD material was studied as a function of time, sorbent mass and concentration. The influence of these parameters on the adsorption capacity was evaluated using the batch method. Results of adsorption experiments and kinetic data showed that (i) the CHITOD adsorbent exhibited high sorption capacities toward BB 3; (II) the Langmuir equation represented the best fit of experimental data; (iii) the dye sorption on material was exothermic and spontaneous in nature; (iv) the kinetic measurements showed that the process was rapid; (v) the adsorption kinetics followed a pseudo-second order model; and (vi) the sorption was dependent on the presence of sulfonate groups. Non-linear method was also found to be more appropriate method for estimating the isotherm and kinetic parameters. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Capacity, Adsorption Kinetics, Aqueous Solutions, Basic Blue 3, Batch, Batch Method, Capacity, Cationic Dye, Chi-Square, Chitosan, Concentration, Correlation Coefficient, Data, Dye, Exothermic, Experimental, Experiments, Function, Isotherm, Kinetic, Kinetic and Isotherm Models, Kinetic Parameters, Kinetics, Langmuir, Langmuir Equation, Model, Non-Linear, Non-Linear Method, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second Order Model, Pseudo-Second-Order, Removal, Solutions, Sorbent, Sorption

? Meenakshi, S., Sundaram, C.S. and Sukumar, R. (2008), Enhanced fluoride sorption by mechanochemically activated kaolinites. Journal of Hazardous Materials, 153 (1-2), 164-172.

Full Text: 2008\J Haz Mat153, 164.pdf

Abstract: Kaolinite clay obtained from the mines was processed and studied for its fluoride sorption capacity. The surface area of the clay mineral was increased from 15.11 m(2)/g (raw) to 32.43 m(2)/g (activated) by mechanochemical activation. Batch adsorption studies were conducted to optimize various equilibrating conditions like the effect of contact time, dosage, pH for both raw and micronized kaolinites (RK and MK). The effect of other interfering anions on the defluoridation capacity (DC) of the sorbents was studied. Sorption of fluoride by the sorbents was observed over a wide pH range of 3-11. The studies revealed there is an enhanced fluoride sorption on MK. FTIR and XRD were used for the characterization of the sorbent. The surface morphology of the clay material was observed using SEM. The adsorption of fluoride was studied at three different temperatures, viz., 303, 313 and 323 K. The sorption data obtained at optimized conditions were subjected to Freundlich and Langnmir isotherms. Sorption intensity (1/n) (0.770-0.810) has been evaluated using Freundlich isotherm, whereas the values of sorption capacity Q(0) (0.609, 0.714 and 0.782 mg/g) and binding energy b (0.158, 0.145 and 0.133 L/mg) at three different temperatures have been estimated using Langmuir isotherm. Adsorption process was found to be controlled by both Freundlich and Langmuir isotherms. Thermodynamic studies revealed that the sorption of fluoride on MK is endothermic and a spontaneous process. The kinetic studies indicate that the sorption of fluoride on MK follows pseudo-first-order and intraparticle diffusion models. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activation, Adsorption, Adsorption Isotherms, Alumina, Anions, Aqueous-Solution, Batch, Batch Adsorption, Capacity, Characterization, Clay, Defluoridation, Diffusion, Effluent, Energy, Equilibrium, Fluoride, Fluoride Removal, Freundlich, Freundlich and Langmuir Isotherms, Freundlich Isotherm, FTIR, Intraparticle Diffusion, Isotherm, Isotherms, Kaolin, Kaolinite, Kaolinite Clay, Kinetic, Kinetics, Kinetics, Langmuir, Langmuir Isotherm, Langmuir Isotherms, Micronized Kaolin, pH, Pseudo-First-Order, Removal, SEM, Sorbent, Sorption, Temperature, Thermodynamic, Thermodynamic Studies, Water, XRD

? Yildiz, Y.Ş. (2008), Optimization of Bomaplex Red CR-L dye removal from aqueous solution by electrocoagulation using aluminum electrodes. Journal of Hazardous Materials, 153 (1-2), 194-200.

Full Text: 2008\J Haz Mat153, 194.pdf

Abstract: In this paper, Taguchi method was applied to determine the optimum dye removal from aqueous solution by electrocoagulation using aluminum electrodes. An orthogonal array (OA16) experimental design that allows to investigate the simultaneous variations of five parameters (initial dye concentration, initial pH of the solution, supporting electrolyte concentration, supporting electrolyte type and current density) having four levels was employed to evaluate the effects of experimental parameters. Performance measure analysis was followed by performing a variance analysis, in order to determine the optimum levels and relative magnitude of the effect of parameters. Because the desired characteristic for response has been maximum decolorization, Taguchi’s [`]the larger the better’ performance formula was used. While the optimum conditions were found to be initial dye concentration of 100 mg, L, initial pH of the solution of 3, supporting electrolyte concentration of 0.0 mM, supporting electrolyte type of CaCl₂ and current density of 0.50 mA, cm². Under these optimum conditions, energy consumption is 0.607 k Wh, kg ye, when the system evaluated also based on the energy consumptions it can be said that optimum conditions should be modified as follows: supporting electrolyte concentration of 2.5 mM; supporting electrolyte type NaCl, for 100 mg, L initial dye concentration; initial pH of the solution of 3; current density of 0.50 mA, cm².

Keywords: Aluminum, Analysis, Aqueous Solution, Concentration, Consumption, Decolorization, Design, Dye, Dye Removal, Electrocoagulation, Energy, Energy Consumption, Experimental, Experimental Design, Measure, Modified, NaCl, Optimization, Performance, pH, Removal, Solution, Taguchi Method

? Ncibia, M.C. (2008), Applicability of some statistical tools to predict optimum adsorption isotherm after linear and non-linear regression analysis. Journal of Hazardous Materials, 153 (1-2), 207-212.

Full Text: 2008\J Haz Mat153, 207.pdf

Abstract: In any single component isotherm study, determining the best-fitting model is a key analysis to mathematically describe the involved sorption system and, therefore, to explore the related theoretical assumptions. Hence, several error calculation functions have been widely used to estimate the error deviations between experimental and theoretically predicted equilibrium adsorption values (Qe,expvs. Qe,theo as X- and Y-axis, respectively), including the average relative error deviation, the Marquardt’s percent standard error deviation, the hybrid fractional error function, the sum of the squares of the errors, the correlation coefficient and the residuals. In this study, five other statistical functions are analysed to investigate their applicability as suitable tools to evaluate isotherm model fitness, namely the Pearson correlation coefficient, the coefficient of determination, the Chi-square test, the F-test and the Student’s T-test, using the commonly-used functions as references. The adsorption of textile dye onto Posidonia oceanica seagrass fibres was carried out, as study case, in batch mode at 20°C. Besides, and in order to get an overall approach of the possible utilization of these statistical functions within the studied item, the examination was realized for both linear and non-linear regression analysis. The related results showed that, among the five studied statistical tools, the χ² and Student’s T-tests were suitable to determine the best-fitting isotherm model for the case of linear modelling approach. On the other hand, dealing with the non-linear analysis, despite the Student’s T-test, all the other functions gave satisfactorily results, by agreeing the commonly-used error functions calculation.

Keywords: Adsorption, Adsorption Isotherm, Analysis, Approach, Assumptions, Batch, Batch Mode, Calculation, Chi-Square, Correlation, Correlation Coefficient, Determination, Dye, Equilibrium, Error, Error Calculation, Error Function, Errors, Examination, Experimental, Fitness, Function, Functions, Hybrid, Isotherm, Isotherm Model, Mode, Model, Modelling, Non-Linear Analysis, Non-Linear Regression, Nonlinear Analysis, Nonlinear Regression, Posidonia Oceanica, References, Regression, Regression Analysis, Residuals, Sorption, Standard, Textile Dye, Utilization

? Lata, H., Mor, S., Garg, V.K. and Gupta, R.K. (2008), Removal of a dye from simulated wastewater by adsorption using treated parthenium biomass. Journal of Hazardous Materials, 153 (1-2), 213-220.

Full Text: 2008\J Haz Mat153, 213.pdf

Abstract: In the present study adsorption of rhodamine-B from aqueous solution on formaldehyde treated parthenium biomass (WC) and phosphoric acid treated parthenium carbon (PWC) was studied. Aqueous solutions of various concentrations (50-500 mg/l) were shaken with certain amount of adsorbent to determine the adsorption capacity of rhodamine-B on WC and PWC. The effectiveness of formaldehyde treated parthenium biomass (WC) and phosphoric acid treated parthenium carbon (PWC) in adsorbing rhodamine-B from aqueous solution has been studied as a function of agitation time, adsorbent dose, initial dye concentration and pH. The adsorption capacities of the studied adsorbents were in the order PWC > WC. Initial pH had negligible effect on the adsorption capacity. Maximum dye was sequestered from the solution within 60 min after the start of every experiment. After that, the concentration of rhodamine-B in the liquid-phase remained constant. The adsorption of rhodamine-B onto PWC and WC followed second-order kinetic model. Adsorption data were modeled using both Langmuir and Freundlich classical adsorption isotherms. The adsorption capacity Q(0) was 59.17 mg/g at initial pH 7.0 for the particle size 0.3-1.0 mm for phosphoric acid treated parthenium carbon (PWC). The FT-IR spectra of the adsorbents were recorded to explore number and position of functional groups available for the binding of dye cation onto studied adsorbents. SEMs of the adsorbents were recorded to explore the morphology of the studied adsorbents. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Adsorbent Dose, Adsorbents, Adsorption, Adsorption Isotherms, Agricultural Waste, Aqueous Solution, Aqueous-Solution, Basic Dye, Biomass, Capacity, Carbon, Cation, Congo Red, Dye, Effectiveness, Equilibrium, Formaldehyde, Freundlich, FT-IR, FTIR, Function, Isotherms, Kinetic, Kinetic Model, Kinetics, Langmuir, Malachite Green, Methylene-Blue, Model, Morphology, Parthenium, Particle Size, pH, Phosphoric Acid, Removal, Rhodamine-B, Rights, Size, Solution, Wastewater

? Singh, C.K., Sahu, J.N., Mahalik, K.K., Mohanty, C.R., Mohan, B.R. and Meikap, B.C. (2008), Studies on the removal of Pb(II) from wastewater by activated carbon developed from Tamarind wood activated with sulphuric acid. Journal of Hazardous Materials, 153 (1-2), 221-228.

Full Text: 2008\J Haz Mat153, 221.pdf

Abstract: The low-cost activated carbon were prepared from Tamarind wood material by chemical activation with sulphuric acid for the adsorption of Pb(II) from dilute aqueous solution. The activated carbon developed shows substantial capacity to adsorb Pb(II) from dilute aqueous solutions. The parameters studied include physical and chemical properties of adsorbent, pH, adsorbent dose, contact time and initial concentrations. The kinetic data were best fitted to the Lagergren pseudo-first-order and pseudo-second order models. The isotherm equilibrium data were well fitted by the Langmuir and Freundlich models. The maximum removal of Lead(II) was obtained 97.95% (experimental) and 134.22 mg/g (from Langmuir isotherm model) at initial concentration 40 mg/l, adsorbent dose 3 g/l and pH 6.5. This high uptake showed Tamarind wood activated carbon as among the best adsorbents for Pb(H). (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Activation, Adsorbent, Adsorbent Dose, Adsorbents, Adsorption, Aqueous Solution, Aqueous Solutions, Capacity, Carbon, Chemical, Chemical Activation, Concentration, Data, Equilibrium, Experimental, Freundlich, Isotherm, Isotherm Model, Kinetic, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Lead(II), Model, Models, Pb(II), pH, Physical, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second Order, Pseudo-Second-Order, Removal, Solution, Solutions, Sulphuric Acid, Uptake, Wastewater, Wastewater Treatment, Wood

? Zhu, B., Fan, T. and Zhang, D. (2008), Adsorption of copper ions from aqueous solution by citric acid modified soybean straw. Journal of Hazardous Materials,