Personal Research Database

181 (1-3), 514-520.

Full Text: 2010\J Haz Mat181, 514.pdf

Abstract: Manganese removal from mining-affected waters is an important challenge for the mining industry. Addressed herein is this issue in both batch and continuous conditions. Batch experiments were carried Out with synthetic solutions, at 23 +/- 2°C, initial pH 5.5 and 8.3 g limestone/L Similarly, continuous tests were performed with a 16.5 mg/L Mn²⁺ mine water, at 23°C, initial pH 8.0 and 20.8 g limestone/L Calcite limestone gave the best results and its fine grinding proved to the most effective parameter for manganese removal. In either synthetic solutions or industrial effluents, the final manganese concentration was below 1 mg/L A change in limestone surface zeta potential is observed after manganese removal and manganese carbonate formation was suggested by IR spectroscopy. The conclusion is that limestone can remove manganese from industrial effluents for values that comply with environmental regulations. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Acid Mine Drainage, ATR-IR, Batch, Batch Experiments, Calcite, Calcite Surface, Dolomite, Drainage, Industrial Effluents, Limestone, Manganese, Mine Waters, Passivation, pH, Precipitation, Removal, Sorption, Sulfate, Treatment, USA, Water, Water Treatment, Zeta Potential

? Haque, E., Lee, J.E., Jang, I.T., Hwang, Y.K., Chang, J.S., Jegal, J. and Jhung, S.H. (2010), Adsorptive removal of methyl orange from aqueous solution with metal-organic frameworks, porous chromium-benzenedicarboxylates. Journal of Hazardous Materials, 181 (1-3), 535-542.

Full Text: 2010\J Haz Mat181, 535.pdf

Abstract: Two typical highly porous metal-organic framework (MOF) materials based on chromium-benzenedicarboxylates (Cr-BDC) obtained from Material of Institute Lavoisier with special structure of MIL-101 and MIL-53 have been used for the adsorptive removal of methyl orange (MO), a harmful anionic dye, from aqueous solutions. The adsorption capacity and adsorption kinetic constant of MIL-101 are greater than those of MIL-53, showing the importance of porosity and pore size for the adsorption. The performance of MIL-101 improves with modification: the adsorption capacity and kinetic constant are in the order of MIL-101 < ethylenediamine-grafted MIL-101 < protonated ethylenediamine-grafted MIL-101 (even though the porosity and pore size are slightly decreased with grafting and further protonation). The adsorption capacity of protonated ethylenediamine-grafted MIL-101 decreases with increasing the pH of an aqueous MO solution. These results suggest that the adsorption of MO on the MOF is at least partly due to the electrostatic interaction between anionic MO and a cationic adsorbent. Adsorption of MO at various temperatures shows that the adsorption is a spontaneous and endothermic process and that the entropy increases (the driving force of the adsorption) with MO adsorption. The adsorbent MIL-101s are re-usable after sonification in water. Based on this study, MOFs can be suggested as potential re-usable adsorbents to remove anionic dyes because of their high porosity, facile modification and ready re-activation. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Adsorbents, Adsorption, Adsorption Capacity, Adsorption Kinetic, Anionic Dyes, Aqueous Solution, Aqueous Solutions, Capacity, Catalysis, Coordination Polymers, Driving, Drug-Delivery, Dye, Dye Removal, Dyes, Endothermic, Entropy, Force, Framework, Grafting, Hydrogen, Interaction, Kinetic, Methyl Orange, MO, Modification, MOFs, Performance, pH, Phenol, Porosity, Porous Chromium-Benzenedicarboxylates, Potential, Removal, Rights, Size, Solution, Solutions, Structure, Terephthalate Mil-101, Waste-Water, Water

? Kawasaki, N., Ogata, F. and Tominaga, H. (2010), Selective adsorption behavior of phosphate onto aluminum hydroxide gel. Journal of Hazardous Materials, 181 (1-3), 574-579.

Full Text: 2010\J Haz Mat181, 574.pdf

Abstract: The specific surface area and X-ray diffraction patterns for an aluminum hydroxide gel (AHG) calcined at 300-1150 degrees C, the number of surface hydroxyl groups in the AHG, and the adsorption isotherms of phosphate on AHG were measured in order to develop a phosphate recovery agent. AHG was transformed into gamma- and alpha-alumina by the calcinations treatment. The amount of phosphate adsorbed onto AHG increases at calcining temperatures of 300-700 degrees C and decreases above a calcining temperature of 800 degrees C. It was found that AHG selectively adsorbs phosphate ions, but not other anions, and shows the highest adsorption capacity at pH 4-6. Further, the alkali resistance of AHG increased with calcination, and more than 80% of the phosphate adsorbed with an NaOH aqueous solution underwent desorption. The addition of colloidal alumina and colloidal silica resulted in the formation of granules of 500-840 mu m size. The amount of phosphate adsorbed onto AHG after granulation was similar to that before granulation. Thus, the phosphate absorption capacity of AHG did not decrease after granulation suggesting that AHG can be used as a phosphate adsorbent. Published by Elsevier B.V.

Keywords: Adsorption, Adsorption Capacity, Adsorption Isotherms, Aluminum Hydroxide Gel, Anion, Arsenate, Desorption, Ion-Solid Interactions, Iron, Isotherms, Oxide Hydroxide, pH, Phosphate, Phosphorus, Removal, Silica, Soil, Sorption, Treatment, X-Ray Diffraction

? Liu, Q.Q., Wang, L., Xiao, A.G., Gao, J.M., Ding, W.B., Yu, H.J., Huo, J. and Ericson, M. (2010), Templated preparation of porous magnetic microspheres and their application in removal of cationic dyes from wastewater. Journal of Hazardous Materials, 181 (1-3), 586-592.

Full Text: 2010\J Haz Mat181, 586.pdf

Abstract: Porous magnetic microspheres with large particle size (350-450 m) were prepared with sulfonated macroporous polydivinylbenzene as a template. The preparation process included ferrous ion exchange and following oxidation by hydrogen peroxide. The results showed that the weight fraction of magnetic nanoparticles exceeded 20 wt% in microspheres after the preparation process was repeated three times. X-ray diffraction profiles indicated that the crystalline phase of as-formed magnetic nanoparticles was magnetite (Fe3O4). TEM images revealed rod-like magnetite crystal after the first oxidation cycle, however, the crystal morphologies were transferred into random shape after more oxidation cycles. The applicability of porous magnetic microspheres for removal of cationic dyes from water was also explored. The results exhibited that basic fuchsin and methyl violet could be quickly removed from water with high efficiency. More importantly, the magnetic microspheres could be easily regenerated and repeatedly employed for wastewater treatment. Therefore, a novel methodology was provided for fast removal cationic dyes from wastewater. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Acid) Hydrogels, Adsorption, Aqueous-Solutions, Basic Fuchsin, Cationic Dye, Controlled Drug-Release, Delivery, Dyes, Ion Exchange, Iron-Oxide Nanoparticles, Magnetic Microspheres, Methyl-Violet, Nanoparticles, Oxidation, Polystyrene, Regeneration, Removal, Shell, TEM, Treatment, Wastewater, Wastewater Treatment, Water, Weight, X-Ray Diffraction

? Klimaviciute, R., Bendoraitiene, J., Rutkaite, R. and Zemaitaitis, A. (2010), Adsorption of hexavalent chromium on cationic cross-linked starches of different botanic origins. Journal of Hazardous Materials, 181 (1-3), 624-632.

Full Text: 2010\J Haz Mat181, 624.pdf

Abstract: The influence of origin of native starch used to obtain cationic cross-linked starch (CCS) on the adsorption of Cr(VI) onto CCS has been investigated. CCS granule size is influenced by the botanic source of native starch. The equilibrium adsorption of Cr(VI) onto CCS was described by the Langmuir, Freundlich, Dubinin-Radushkevich and Temkin models. The more equal the adsorption energy of the quaternary ammonium groups in CCS granule as indicated by low value of change of Temkin adsorption energy Delta E-T the greater amount of Cr(VI) was adsorbed onto CCS. The value of Delta E-T decreased and sorption capacity of CCS increased with the decrease of CCS granule size and with the increase of number of amorphous regions in CCS granules. The affinity of dichromate anions increases and adsorption proceeds more spontaneously when Cr(VI) is adsorbed onto more amorphous CCS. Adsorption process of Cr(VI) onto such CCS is more exothermic and order of system undergoes major changes during adsorption. After the adsorption on CCS Cr(VI) could be regenerated by incineration at temperature of 800 degrees C. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Amphoteric Starch, Aqueous Systems, Cationic Cross-Linked Starch, Chromium, Cr(VI), Equilibrium, Freundlich, Hexavalent Chromium, Kinetics, Langmuir, Sorption, System, Temkin

? Aksakal, O. and Ucun, H. (2010), Equilibrium, kinetic and thermodynamic studies of the biosorption of textile dye (Reactive Red 195) onto Pinus sylvestris L. Journal of Hazardous Materials, 181 (1-3), 666-672.

Full Text: 2010\J Haz Mat181, 666.pdf

Abstract: This study investigated the biosorption of Reactive Red 195 (RR 195), an azo dye, from aqueous solution by using cone biomass of Pinus sylvestris Linneo. To this end, pH. initial dye concentration, biomass dosage and contact time were studied in a batch biosorption system. Maximum pH for efficient RR 195 biosorption was found to be 1.0 and the initial RR 195 concentration increased with decreasing percentage removal. Biosorption capacity increased from 6.69 mg/g at 20ºC to 7.38 mg/g at 50ºC for 200 mg/L dye concentration. Kinetics of the interactions was tested by pseudo-first-order and pseudo-second-order kinetics, the Elovich equation and intraparticle diffusion mechanism. Pseudo-second-order kinetic model provided a better correlation for the experimental data studied in comparison to the pseudo-first-order kinetic model and intraparticle diffusion mechanism. Moreover, the Elovich equation also showed a good fit to the experimental data. Freundlich and Langmuir adsorption isotherms were used for the mathematical description of the biosorption equilibrium data. The activation energy of biosorption (Ea) was found to be 8.904 kJ/mol by using the Arrhenius equation. Using the thermodynamic equilibrium coefficients obtained at different temperatures, the study also evaluated the thermodynamic constants of biosorption (ΔGº, ΔHº and ΔS). The results indicate that cone biomass can be used as an effective and low-cost biosorbent to remove reactive dyes from aqueous solution. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activation, Activation Energy, Adsorption, Adsorption Isotherms, Agricultural Waste, Aqueous Solution, Aqueous-Solution, Azo Dye, Batch, Biomass, Biosorbent, Biosorption, Capacity, Comparison, Concentration, Correlation, Data, Decolorization, Diffusion, Dye, Dyes, Elovich, Elovich Equation, Energy, Equilibrium, Experimental, Freundlich, Intraparticle Diffusion, Isotherms, Kinetic, Kinetic Model, Kinetics, Langmuir, Low Cost, Mechanism, Model, Oxidation, pH, Pinus Sylvestris, Pinus Sylvestris L., Pseudo First Order, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Pseudo-Second-Order Kinetics, Reactive Dyes, Reactive Red 195, Removal, Rights, Solution, Textile Dye, Thermodynamic, Thermodynamic Studies

? Dhaouadi, A., Monser, L. and Adhoum, N. (2010), Removal of rotenone insecticide by adsorption onto chemically modified activated carbons. Journal of Hazardous Materials, 181 (1-3), 692-699.

Full Text: 2010\J Haz Mat181, 692.pdf

Abstract: The removal of rotenone from synthetic and real wastewaters using modified activated carbons has been investigated. In order to enhance the removal capacity of rotenone, activated carbon was chemically modified through impregnation with NH₃ and (NH₄)₂S₂O₈ solutions. The resulting carbons were found to present different surface chemistries, while possessing similar textural properties. The adsorption data obtained at 298 K, on plain and modified carbons were well represented by the Langmuir isotherm model (R² > 0.997). The highest adsorption capacity (Q(m) = 270.3 mg g^-1) was obtained with the ammonia-treated activated carbon. The relative effect of different surface groups on adsorption capacities were found to be in accordance with the pi-pi dispersive interaction model. The adsorption kinetic models have provided useful insights into rotenone adsorption mechanism. It was concluded that rotenone sorption process followed pseudo-second order model and was controlled by intra-particle diffusion mechanism with a significant contribution of film diffusion. The successful adsorptive removal of rotenone, from real wastewater samples on fixed bed columns, have demonstrated the suitability of this method as an effective alternative solution for the treatment of contaminated wastewaters. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Activated Carbons, Adsorption, Adsorption Capacities, Adsorption Capacity, Adsorption Isotherm, Adsorption Kinetic, Adsorption Mechanism, Alternative, Aqueous-Solutions, Basic Sites, Capacity, Carbon, Data, Degradation, Diffusion, Film Diffusion, Fixed Bed, Impregnation, Induced Apoptosis, Insecticide, Interaction, Intra-Particle Diffusion, Intraparticle Diffusion, Isotherm, Isotherm Model, Kinetic, Kinetic Models, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Mechanism, Model, Models, Modified, NH₃, Parkinsons-Disease, Phenol, Pore Structure, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second Order Model, Pseudo-Second-Order, Removal, Rights, Rotenone, Solution, Solutions, Sorption, Sorption Process, Surface, Surface Chemistry, Surface Groups, Surface-Chemistry, Treatment, Waste-Water, Wastewater, Wastewaters

? Sprynskyy, M., Kovalchuk, I. and Buszewski, B. (2010), The separation of uranium ions by natural and modified diatomite from aqueous solution. Journal of Hazardous Materials, 181 (1-3), 700-707.

Full Text: 2010\J Haz Mat181, 700.pdf

Abstract: In this work the natural and the surfactant modified diatomite has been tested for ability to remove uranium ions from aqueous solutions. Such controlling factors of the adsorption process as initial uranium concentration, pH, contact time and ionic strength have been investigated. Effect of ionic strength of solution has been examined using the solutions of NaCl, Na₂CO₃ and K₂SO₄. The pseudo-first order and the pseudo-second order models have been used to analyze the adsorption kinetic results, whereas the Langmuir and the Freundlich isotherms have been used to the equilibrium adsorption data. The effects of the adsorbent modification as well as uranium adsorption on the diatomite surface have been studied using X-ray powder diffraction, scanning electron microscopy and FTIR spectroscopy. The maximum adsorption capacities of the natural and the modified diatomite towards uranium were 25.63 mu mol/g and 667.40 mu mol/g, respectively. The desorptive solutions of HCl, NaOH, Na₂CO₃, K₂SO₄, CaCO₃, humic acid, cool and hot water have been tested to recover uranium from the adsorbent. The highest values of uranium desorption (86%) have been reached using 0.1 M HCl. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Acid, Adsorbent, Adsorption, Adsorption Capacities, Adsorption Kinetic, Aqueous Solution, Aqueous Solutions, Concentration, Data, Desorption, Diatomite, Electron Microscopy, Equilibrium, Freundlich, FTIR, FTIR Spectroscopy, Humic Acid, Ionic Strength, Ions, Isotherm Adsorption, Isotherms, Kinetic, Kinetic Adsorption, Langmuir, Models, Modification, Modified, Modified Diatomite, Nacl, NaOH, Natural, pH, Pseudo First Order, Pseudo Second Order, Pseudo-First Order, Pseudo-First-Order, Pseudo-Second Order, Pseudo-Second-Order, Removal, Rights, Scanning Electron Microscopy, Separation, Solution, Solutions, Sorption, Spectroscopy, Strength, Surface, Surfactant, Thermodynamic Behavior, Time, Uranium, Uranyl Ions, Waste, Water, Work, X-Ray, Zeolite

? Karunakaran, C., Narayanan, S. and Gomathisankar, P. (2010), Photocatalytic degradation of 1-naphthol by oxide ceramics with added bacterial disinfection. Journal of Hazardous Materials, 181 (1-3), 708-715.

Full Text: 2010\J Haz Mat181, 708.pdf

Abstract: 1-Naphthol photodegrades on the surfaces of TiO2, ZnO, CeO2, CdO, WO3, Co3O4, Sb2O3, ZrO2, La2O3, Y2O3, Pr6O11, Sm2O3 and Al2O3, albeit at different efficiencies, and all the oxides show sustainable photocatalytic activity. The degradation conforms to the Langmuir-Hinshelwood kinetic model and enhances with the intensity of illumination. Dissolved oxygen is essential for the degradation. ZnO and TiO2 anatase are the most efficient photocatalysts to degrade 1-naphthol. ZnO wurtzite, besides serving as an effective photocatalyt to degrade 1-naphthol, also acts as a bactericide; it inactivates E.coli even in absence of direct light. At a loading of 0.8 g L-1, it kills about 44% of 2.5 x 10(12) CFU mL(-1) E. coil in 1/2 h under dark condition. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: 2-Naphthol, Adsorption, Alpha-Naphthol, Bactericidal Activity, Beta-Naphthol, CeO₂, Degradation, Hydroxyl Radicals, Kinetic, Kinetic Model, Oxidation, Photodegradation, Photodegradation, Semiconductor, Surfaces, TiO₂, Titanium-Dioxide, Water, ZrO₂

? Wu, X.D., Liu, S.A., Lin, F. and Weng, D.A. (2010), Nitrate storage behavior of Ba/MnOx-CeO₂ catalyst and its activity for soot oxidation with heat transfer limitations. Journal of Hazardous Materials, 181 (1-3), 722-728.

Full Text: 2010\J Haz Mat181, 722.pdf

Abstract: A BaMnCe ternary catalyst was prepared by impregnating barium acetate on MnOx-CeO2 mixed oxides, with the monoxide supported catalysts and the solid solution support as references. The activities of the catalysts for soot oxidation were evaluated in the presence of NO under an energy transference controlled regime. BaMnCe presented the lowest maximal soot oxidation rate temperature at 393 degrees C among the catalysts investigated. Although BaMnCe experienced a loss in the specific surface area and low-temperature redox property due to blocking of the support pores by barium carbonate, its superior soot oxidation activity highlighted the importance of relatively stable bidentate/monodentate nitrates coordinated to Mnx+ and Cex+ sites and more stable ionic barium nitrate. About half of the nitrates stored on this catalyst decomposed within the temperature interval of 350-450 degrees C, and the ignition temperature of soot decreased significantly with involvement of the nitrates or NO2 released. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Ba, K, CeO₂ Catalyst, Barium, Co, Ba, K, ZrO₂, Combustion, Diesel Soot, Mixed Oxides, Mnox-CeO₂ Mixed Oxides, Nitrate, NOx Adsorption, Oxidation, Performance, Potassium, References, Soot Oxidation, Stability, Temperature

? Bouyarmane, H., El Asri, S., Rami, A., Roux, C., Mahly, M.A., Saoiabi, A., Coradin, T. and Laghzizil, A. (2010), Pyridine and phenol removal using natural and synthetic apatites as low cost sorbents: Influence of porosity and surface interactions. Journal of Hazardous Materials, 181 (1-3), 736-741.

Full Text: 2010\J Haz Mat181, 736.pdf

Abstract: A natural phosphate rock and two synthetic mesoporous hydroxyapatites were evaluated for the removal of pyridine and phenol from aqueous solutions. Experiments performed by the batch method showed that the sorption process occurs by a first order reaction for both pyridine and phenol. In contrast, the Freundlich model was able to describe sorption isotherms for phenol but not for pyridine. In parallel, the three apatites exhibit similar pyridine sorption capacities whereas phenol loading was in agreement with their respective specific surface area. This was attributed to the strong interaction arising between pyridine and apatite surface that hinders further inter-particular diffusion. This study suggests that, despite its low specific surface area, natural phosphate rock may be used as an efficient sorbent material for specific organic pollutants,with comparable efficiency and lower processing costs than some activated! carbons. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated Carbons, Adsorption, Agricultural Waste Materials, Amendment, Apatite, Aqueous Solutions, Aqueous-Solution, Batch, Batch Method, Cost, Costs, Derivatives, Diffusion, Efficiency, First, First Order, Freundlich, Freundlich Model, Hydroxyapatite, Interaction, Isotherms, Kinetics, Loading, Low Cost, Mesoporous, Model, Natural, Organic, Phenol, Phenol Removal, Phosphate, Phosphate Rock, Porosity, Pyridine, Remediation, Removal, Rights, Solutions, Sorbent, Sorbents, Sorption, Sorption Isotherms, Sorption Process, Specific Surface, Specific Surface Area, Surface, Surface Area

? Jalil, A.A., Triwahyono, S., Adam, S.H., Rahim, N.D., Aziz, M.A.A., Hairom, N.H.H., Razali, N.A.M., Abidin, M.A.Z. and Mohamadiah, M.K.A. (2010), Adsorption of methyl orange from aqueous solution onto calcined Lapindo volcanic mud. Journal of Hazardous Materials, 181 (1-3), 755-762.

Full Text: 2010\J Haz Mat181, 755.pdf

Abstract: In this study, calcined Lapindo volcanic mud (LVM) was used as an adsorbent to remove an anionic dye, methyl orange (MO), from an aqueous solution by the batch adsorption technique. Various conditions were evaluated, including initial dye concentration, adsorbent dosage, contact time, solution pH, and temperature. The adsorption kinetics and equilibrium isotherms of the LVM were studied using pseudo-first-order and -second-order kinetic equations, as well as the Freundlich and Langmuir models. The experimental data obtained with LVM fits best to the Langmuir isotherm model and exhibited a maximum adsorption capacity (q(max)) of 333.3 mg g^-1: the data followed the second-order equation. The intraparticle diffusion studies revealed that the adsorption rates were not controlled only by the diffusion step. The thermodynamic parameters, such as the changes in enthalpy, entropy, and Gibbs free energy, showed that the adsorption is endothermic, random and spontaneous at high temperature. The results indicate that LVM adsorbs MO efficiently and could be utilized as a low-cost alternative adsorbent for the removal of anionic dyes in wastewater treatment. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorbent Dosage, Adsorption, Adsorption Capacity, Adsorption Kinetics, Alternative, Anionic Dyes, Aqueous Solution, Basic-Dyes, Batch, Batch Adsorption, Biosorption, Calcined, Capacity, Changes, Concentration, Congo-Red, Data, Diffusion, Dye, Dyes, Endothermic, Energy, Enthalpy, Entropy, Equilibrium, Equilibrium Isotherms, Experimental, Fly-Ash, Freundlich, Gibbs Free Energy, Intraparticle Diffusion, Isotherm, Isotherm Model, Isotherms, Kinetic, Kinetic Equations, Kinetics, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Lapindo Volcanic Mud, Low Cost, Methyl Orange, Mo, Model, Models, Montmorillonite, pH, Pseudo First Order, Pseudo-First-Order, Rates, Removal, Rights, Second Order, Second-Order, Second-Order Equation, Solution, Temperature, Thermodynamic, Thermodynamic Parameters, Thermodynamics, Treatment, Wastewater, Wastewater Treatment

? Park, J., Won, S.W., Mao, J., Kwak, I.S. and Yun, Y.S. (2010), Recovery of Pd(II) from hydrochloric solution using polyallylamine hydrochloride-modified Escherichia coli biomass. Journal of Hazardous Materials, 181 (1-3), 794-800.

Full Text: 2010\J Haz Mat181, 794.pdf

Abstract: A new type of biosorbent able to bind anionic metals was developed by cross-linking of waste biomass Escherichia coil with polyallylamine hydrochloride (PAH). The PAH-modified biomass was investigated for the removal and recovery of Pd(II), in the chloro-complex form, from aqueous solution. The performance of the PAH-modified biomass was evaluated in terms of the following parameters: the solution pH, contact time and initial metal concentration. In the pH edge experiments, the uptake of Pd(II) increased with increasing pH. Pd(II) biosorption proceeded rapidly in the first 10 min, with almost complete equilibrium being achieved within 60min. Moreover, the isotherm data showed that the maximum uptakes of Pd(II) were 265.3 mg/g at pH 3 and 212.9 mg/g at pH 2, respectively. After incineration of the Pd-loaded PAH-modified biomass, metallic palladium was recovered in the ash. X-ray photoelectron spectroscopy (XPS) results confirmed that the palladium was recovered in two valency states: zero-valent and divalent palladium (as PdO). Therefore, we concluded that PAH-modified biomass is a useful and cost-effective biosorbent for the recovery of anionic precious metals as chloro-complex solutions containing hydrochloric acid produced from metal refining processes. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Biomass, Biosorption, Chelating Resin, Complete, Contact Time, Corynebacterium-Glutamicum, Cross-Linked Chitosan, Enhancement, Equilibrium, Escherichia Coli, Gold(III), Incineration, Isotherm, Palladium, Palladium Sorption, pH, Platinum(IV), Polyallylamine Hydrochloride, Preconcentration, Recovery, Removal, X-Ray Photoelectron Spectroscopy, XPS

? Zhang, H., Tang, Y., Cai, D.Q., Liu, X.A., Wang, X.Q., Huang, Q. and Yu, Z.L. (2010), Hexavalent chromium removal from aqueous solution by algal bloom residue derived activated carbon: Equilibrium and kinetic studies. Journal of Hazardous Materials,