Personal Research Database

172 (2-3), 1150-1155.

Full Text: 2009\J Haz Mat172, 1150.pdf

Abstract: This paper deals with the removal of Cadmium from aqueous solutions by polysaccharide produced from Paenibacillus polymyxa. The effects of contact time, initial metal ions concentration, mass of the polysaccharide and pH were studied. The Freundlich and Dubinin-Radushkevich (D-R) models have been applied and the equilibrium adsorption was found to best fit the Dubinin-Radushkevich adsorption isotherm based on the coefficient of correlation, R-2. The maximum Cd²⁺ uptake was 520.09 mg g^-1, An empirical modeling was performed by using a 2(3) full factorial design and a regression equation for adsorption of Cd²⁺ was determined from the data. The pH and the initial concentration of Cadmium are the most significant parameters affecting Cd²⁺ adsorption followed by the mass of the polysaccharide. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorbents, Adsorption, Adsorption, Adsorption Isotherm, Aqueous Solution, Aqueous Solutions, Biosorption, Cadmium, Cd²⁺, Concentration, Contact Time, Copper(II), Correlation, Data, Design, Equilibrium, Exopolysaccharide, Factorial Design, Freundlich, Heavy-Metal Ions, Ions, Isotherm, Lead(II), Metal, Metal Ions, Mixtures, Modeling, Models, Paenibacillus polymyxa, pH, Polysaccharide, Polysaccharides, Regression, Removal, Rights, Solution, Solutions, Sorption Isotherm Models, Uptake, Waste-Water

? Rodríguez, A., García, J., Ovejero, G. and Mestanza, M. (2009), Adsorption of anionic and cationic dyes on activated carbon from aqueous solutions: Equilibrium and kinetics. Journal of Hazardous Materials, 172 (2-3), 1311-1320.

Full Text: 2009\J Haz Mat172, 1311.pdf

Abstract: Activated carbon was utilized as adsorbent to remove anionic dye, Orange II (OII), and cationic dye, Methylene blue (MB), from aqueous solutions by adsorption. Batch experiments were conducted to study the effects of temperature (30-65ºC), initial concentration of adsorbate (300-500 mg L^-1) and pH (3.0-9.0) on dyes adsorption. Equilibrium adsorption isotherms and kinetics were investigated. The equilibrium experimental data were analyzed by the Langmuir, Freundlich. Toth and Redlich-Peterson models. The kinetic data obtained with different carbon mass were analyzed using a pseudo-first order, pseudo-second order, intraparticle diffusion, Bangham and Chien-Clayton equations. The best results were achieved with the Langmuir isotherm equilibrium model and with the pseudo-second order kinetic model. The activated carbon was found to be very effective as adsorbent for MB and Oil from aqueous solutions. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Adsorption, Adsorption Isotherms, Aqueous Solutions, Basic Dye, Carbon, Cationic and Anionic Dyes, Cationic Dye, Cationic Dyes, Concentration, Data, Diffusion, Dye, Dyes, Equilibrium, Equilibrium Model, Experimental, Experiments, Freundlich, Intraparticle Diffusion, Isotherm, Isotherms, Kinetic, Kinetic Model, Kinetics, L1, Langmuir, Langmuir Isotherm, Mb, Mechanism, Methylene Blue, Methylene-Blue Adsorption, Model, Models, Orange II, pH, Pseudo First Order, Pseudo Second Order, Pseudo-First Order, Pseudo-First-Order, Pseudo-Second Order, Pseudo-Second-Order, Redlich-Peterson, Removal, Rights, Solutions, Surface, Temperature, Waste-Water, Wastewater

? Vázquez, G., Calvo, M., Freire, M.S., González-Alvarez, J. and Antorrena, G. (2009), Chestnut shell as heavy metal adsorbent: Optimization study of lead, copper and zinc cations removal. Journal of Hazardous Materials, 172 (2-3), 1402-1414.

Full Text: 2009\J Haz Mat172, 1402.pdf

Abstract: The influence of initial cation concentration, temperature and pH was investigated to optimize Pb²⁺, Cu²⁺ and Zn²⁺ removal from aqueous solutions using acid formaldehyde pre-treated chestnut shell as adsorbent. Experiments were planned according to an incomplete 3(3) factorial experimental design. Under the optimal conditions selected, the metal ion adsorption equilibrium was satisfactorily described by the Langmuir isotherm model. The maximum pre-treated chestnut shell adsorption capacity was obtained for Pb²⁺ ions, 8.5 mg g^-1, and the order of cation affinity was Pb²⁺ > Cu²⁺ > Zn²⁺. A model that considered the effect of axial dispersion was successfully used to describe the fixed-bed adsorption behaviour of Pb²⁺, Cu²⁺ and Zn²⁺ ions at the flow rates essayed. Fourier transform infrared (FTIR) and X-ray photoelectron (XPS) spectroscopies showed that the functional groups involved in metal ions binding included carboxyl, hydroxyl, ether, alcoholic and amino groups. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption, Adsorption Capacity, Adsorption Equilibrium, Aqueous Solutions, Aqueous-Solutions, Behaviour, Binding, Biosorption, Capacity, Castanea-sativa Shell, Cation, Chestnut Shell, Concentration, Copper, Cu²⁺, Design, Dispersion, Equilibrium, Ether, Experimental, Experimental Design, Fixed Bed, Fixed Bed Adsorption, Flow, Formaldehyde, FTIR, Functional Groups, Globulus Bark Extracts, Heavy Metal, Ions, Isotherm, Isotherm Model, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Lead, Metal, Metal Cation, Metal Ion, Metal Ions, Model, Optimization, Oxide-Coated Sand, Pb(II), Pb²⁺, pH, Rates, Removal, Rights, Solutions, Temperature, Waste, X-Ray, XPS, Zinc, Zn²⁺

? Rajic, N., Stojakovic, D., Jevtic, S., Logar, N.Z., Kova

, J. and Kau

i

, V. (2009), Removal of aqueous manganese using the natural zeolitic tuff from the Vranjska Banja deposit in Serbia. Journal of Hazardous Materials, 172 (2-3), 1450-1457.

Full Text: 2009\J Haz Mat172, 1450.pdf

Abstract: The natural zeolite tuff from the Vranjska Banja deposit (Serbia) has been studied as sorbent for Mn(II) ions from aqueous solutions. The zeolite sample containing mainly clinoptilolite (more than 70%) removes Mn(II) ions by ion-exchange process, which was confirmed by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray analysis (EDXS). XPS showed that there is no surface accumulation of Mn but an almost uniform distribution inside the sorbent; EDXS confirmed that Mn(II) replaced the clinoptilolite Na counter ions. The sorption isotherms were studied at 298 K by batch experiments showing that the Mn(II) removal is best described by the Langmuir-Freundlich or Sips model. The kinetics followed the pseudo-second-order model, the activation energy being 128 kJ mol(-1). The intra-particle diffusion is not the rate-controlling step in the sorption of Mn(II) on clinoptilolite. Thermodynamic data suggest spontaneity of the endothermic ion-exchange process in the 298-338 K range. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Accumulation, Activation, Activation Energy, Adsorption, Analysis, Aqueous Solutions, Batch, Batch Experiments, Clinoptilolite, Clinoptilolite, Clusters, Data, Diffusion, Distribution, Drinking-Water, Edx, Endothermic, Energy, Equilibrium, Experiments, Heavy-Metals, Intra Particle Diffusion, Intra-Particle Diffusion, Intraparticle Diffusion, Ion Exchange, Ion-Exchange, Ionexchange, Ions, Isotherms, Kaolinite, Kinetics, Langmuir-Freundlich, Langmuir-Freundlich Isotherm, Manganese, Manganese Removal, Mn²⁺ Ions, Model, Natural, Natural Zeolite, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Removal, Rights, Solutions, Sorbent, Sorption, Sorption Isotherms, Spectroscopy, Surface, Thermodynamic, Thermodynamic Data, X-Ray, X-Ray Photoelectron Spectroscopy, XPS, Zeolite, Zeolitic Tuff

? Gönen, F. and Aksu, Z. (2009), Single and binary dye and heavy metal bioaccumulation properties of Candida tropicalis: Use of response surface methodology (RSM) for the estimation of removal yields. Journal of Hazardous Materials, 172 (2-3), 1512-1519.

Full Text: 2009\J Haz Mat172, 1512.pdf

Abstract: The single and binary effects of initial Remazol Turquoise Blue-G (RTBG) reactive dye and initial copper(II) concentrations on the dye or, and copper(II) bioaccumulation efficiency of C tropicalis was investigated in 10 g l(-1) molasses sucrose containing growth medium at an initial pH value of 4.0 and optimized using response surface methodology (RSM). A 2(2) full factorial central composite design was successfully used for experimental design and analyses of the results. Two numerical correlations fitted to a second-order quadratic equation were obtained to estimate the responses of dye and copper(II) removal yields. The statistical analysis indicated that although relatively high accumulation efficiency of C tropicalis was obtained for the single removal of dye and copper(II), individual uptake of both the components from binary mixture was affected negatively by the addition of other component up to 500 mg l(-1) due to inhibition caused by high concentrations of RTBG dye and copper(II). The optimum combination predicted via RSM confirmed that growing C tropicalis was capable of bioaccumulating RTBG and copper(II) with the maximum yields of 59.2% and 21.3% in the growth medium containing 50 mg l(-1) RTBG and 50 mg l(-1) copper(II) together, respectively. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Analysis, Bioaccumulation, Biosorption, Candida, Candida Tropicalis, Chromium(VI), Copper(II), Copper(II), Decolorization, Design, Experimental, Growth, Heavy Metal, Inhibition, Metal, Methodology, Optimization, pH, pH Value, Reactive Dye, Remazol Turquoise Blue G, Removal, Response Surface Methodology, RSM, Statistical, Synthetic Dyes, Textile Dyes, Uptake, Versicolor

? Chadlia, A., Mohamed, K., Najah, L. and Farouk, M.M. (2009), Preparation and characterization of new succinic anhydride grafted Posidonia for the removal of organic and inorganic pollutants. Journal of Hazardous Materials, 172 (2-3), 1579-1590.

Full Text: 2009\J Haz Mat172, 1579.pdf

Abstract: The present work describes the preparation of new chelating materials derived from Posidonia for adsorption of heavy metal ions and dye in aqueous solution. The first part of this report deals with the chemical modification of Posidonia with succinic anhydride. Thus, we have obtained materials with various succinyl groups contents (from 29.8 to 39.2%). The obtained materials were characterized by infrared and CP/MAS C-13-RMN spectroscopy. The rate of succinyl content of the modified Posidonia was determined by saponification. The second part is devoted to the evaluation of the adsorption capacity of metal ions such as Pb²⁺ and dye such as direct red 75 (DR75) for raw and modified Posidonia materials. Two possible ways for the adsorption of these pollutants are studied: adsorption of each pollutant alone onto these supports, and cumulative adsorption of both metal ions and dye on the same supports. In the last case, the pollutant is adsorbed successively from two different solutions. The effects of pollutants concentration, support dose, pH, contact time and temperature on adsorption of each pollutant were evaluated. The results showed that the raw and modified Posidonia show a high capacity for Pb²⁺ adsorption. The capacity of modified Posidonia saturated with Pb²⁺ to adsorb DR75 was found 147.12 mg g^-1. While the adsorption capacity of the nonsaturated modified Posidonia was equal to 81.63 mg g^-1. The pseudo-second-order model was the best to represent adsorption kinetics of DR75. The pseudo-first-order model would be better for fitting the adsorption kinetic process of Pb²⁺ onto raw and modified Posidonia. The adsorption isotherms of Pb²⁺ could be described by the Jossens equation model. Any of the tested models can describe the adsorption of DR75 onto the studied materials. These results confirm that the adsorption of DR75 from aqueous solution was multilayer. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Capacity, Adsorption Isotherms, Adsorption Kinetic, Adsorption Kinetics, Aquatic Plant, Aqueous Solution, Aqueous-Solutions, Capacity, Characterization, Chemical, Chemical Modification, Concentration, Contact Time, Cumulative, Direct Dye, Dye, Dye Adsorption, Evaluation, First, Grafted, Heavy Metal, Heavy Metal Ions, Heavy Metals, Heavy-Metal Ions, Ions, Isotherms, Kinetic, Kinetics, Lead(II) Ions, Medicago-Sativa Alfalfa, Metal, Metal Ions, Model, Models, Modification, Modified, Modified Cotton, Multilayer, Myriophyllum-Spicatum, Nonliving Biomass, Organic, Pb²⁺, Pb²⁺ Adsorption, pH, Pollutants, Posidonia, Preparation, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Reactive Dyes, Removal, Rights, Saponification, Solution, Solutions, Spectroscopy, Succinic Anhydride, Support, Temperature, Work

? Ramos-Ramírez, E., Ortega, N.L.G., Soto, C.A.C. and Gutíerrez, M.T.O. (2009), Adsorption isotherm studies of chromium(VI) from aqueous solutions using sol-gel hydrotalcite-like compounds. Journal of Hazardous Materials, 172 (2-3), 1527-1531.

Full Text: 2009\J Haz Mat172, 1527.pdf

Abstract: In under-developed countries, industries such as paint and pigment manufacturing, leather tanning, chrome plating and textile processing, usually discharge effluents containing Cr(VI) and Cr(III) into municipal sanitary sewers. It has been reported that Cr(VI) acts as a powerful epithelial irritant and as a human carcinogen. In the present work, hydrotalcite-like compounds with a Mg/Al ratio = 2 were synthesized by the sol-gel method. The hydrotalcite-like compounds and their corresponding thermally treated products were characterized by powder X-ray diffraction, infrared spectroscopy and N-2 adsorption. The hydrotalcite-like compounds and the heated solids were used as adsorbents for Cr(VI) in aqueous solutions. Adsorption isotherm studies of Cr(VI) from aqueous solution are described. The adsorbent capacity was determined using the Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherm models. The Cr(VI) adsorption isotherm data fit best to the Langmuir isotherm model. The maximum Cr(VI) uptake by hydrotalcite and the heated solids was determined using the Langmuir equation and was found to range between 26 and 29 mg Cr(VI)/g adsorbent. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Isotherm, Aqueous, Capacity, Chromium, Chromium(VI), Elsevier, Hydrotalcite, Isotherm, Isotherms, Langmuir Equation, Langmuir Isotherm, Manufacturing, Mg, Models, N-2, Oxide, Physicochemical Properties, Raman, Removal, Route, Sol-Gel, Solutions, Sorption, Spectroscopy, Thermal-Decomposition

? El Shafei, G.S., Nasr, I.N., Hassan, A.S.M. and Mohammad, S.G.M. (2009), Kinetics and thermodynamics of adsorption of cadusafos on soils. Journal of Hazardous Materials, 172 (2-3), 1608-1616.

Full Text: 2009\J Haz Mat172, 1608.pdf

Abstract: Laboratory batch experiments were designed to study the adsorption of cadusafos on two types of soils: clay loamy and sandy, collected from two regions around the Nile Delta in Egypt. The adsorption process is fast reaching equilibrium in 60 min, decreases with increasing soil mass and independent on pH in the range 3-11. The experimental results were well fitted to linear partition model, and to a lesser extent to Freundlich non-linear model, Temkin and Dubinin-Radushkevich models. However, the 1/n parameter of Freundlich relation being of value around one supported the linear partition model. The K-d values obtained from the linear model were 4.20 and 2.74 L/g for sandy and clay soils, respectively. The energy of adsorption calculated from D-R equation was 4.36 and 5.04 kJ/mol for clay and sandy soils, respectively. in the range assigned to physical forces. This kind of weak interaction, together with pH-independence implies that for the studied soils the organic content (that is higher in the clay soil) is not a major parameter in the adsorption of cadusafos. Water movement taking place more readily in sandy soil caused increased uptake relative to the case of clay soil. The higher uptake in sandy soil denotes that cadusafos may be mobile with a potential to leach and eventually pollutes ground water and surface water. The kinetics of adsorption was well fitted by the pseudo-second order equation. The intraparticles diffusion is of lower significance in case of sandy soil than in clay soil. Thermodynamic parameters indicated that the adsorption is spontaneous. endothermic accompanied by increase in entropy. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Aqueous-Solutions, Batch, Batch Experiments, Cadusafos, Chemicals, Clay, Degradation, Desorption, Diffusion, Dr Equation, Egypt, Endothermic, Energy, Entropy, Equilibrium, Experimental, Experiments, Freundlich, Ground Water, Interaction, Kinetics, Kinetics of Adsorption, Mobile, Model, Models, Movement, Nile, Organic, Organic-Matter, Pesticides, Pesticides, pH, Physical, Potential, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second-Order, Removal, Rights, Sandy Soil, Sediments, Significance, Soil, Soils, Sorption, Spontaneous, Surface, Surface Water, Thermodynamic, Thermodynamic Parameters, Thermodynamics, Thermodynamics of Adsorption, Uptake, Value, Water

? Cheng, R.M., Ou, S.J., Li, M.J., Li, Y.J. and Xiang, B. (2009), Ethylenediamine modified starch as biosorbent for acid dyes. Journal of Hazardous Materials, 172 (2-3), 1665-1670.

Full Text: 2009\J Haz Mat172, 1665.pdf

Abstract: This work investigated the sorption performance of the ethylenediamine modified starch (CAS) for the removal of acid dyes from aqueous solutions. The influence of pH on adsorption of acid orange 10 (AO10). acid green 25 (AG25) and amido black 10B (AB10B) was evaluated. The sorption kinetics, equilibrium uptake and desorption of the loaded dyes in sodium sulfate solution were studied. It was found that the interaction mechanism was based on electrostatic attraction and hydrogen bonding. The adsorption of AG25 and AB10B followed pseudo-second-order model, whereas AO10 followed both pseudo-first-order and pseudo-second-order models. The best isotherm was Langmuir equation and the capacities followed the sequence AB10B > AC25 > AO10. The different behaviors of individual dyes adsorption on CAS were largely dependent on the number of hydrophilic functional groups, which had strong tendency to form hydrogen bonds with the biosorbent. Dye release in sodium sulfate solutions was determined by the salt concentration and nature of dyes. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Acid Dye, Acid Dyes, Acid Green 25, Adsorbents, Adsorption, Adsorption, Aqueous Solutions, Aqueous-Solutions, Azo Dyes, Biosorbent, Chitosan, Concentration, Degradation, Desorption, Dye, Dyes, Equilibrium, Ethylenediamine, Ethylenediamine Modified Starch, Functional Groups, Hydrogen, Hydrogen Bonding, Interaction, Isotherm, Kinetics, Langmuir, Langmuir Equation, Mechanism, Model, Models, Modified, Modified Starch, Performance, pH, Polysaccharides, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Release, Removal, Rice, Rights, Salt, Salt Concentration, Sodium, Solution, Solutions, Sorption, Sorption Kinetics, Starch, Sulfate, Thermogravimetry, Uptake, Work

? Huang, X., Liao, X.P. and Shi, B. (2010), Tannin-immobilized mesoporous silica bead (BT-SiO₂) as an effective adsorbent of Cr(III) in aqueous solutions. Journal of Hazardous Materials, 173 (1-3), 33-39.

Full Text: 2010\J Haz Mat173, 33.pdf

Abstract: This study describes a new approach for the preparation of tannin-immobilized adsorbent by using mesoporous silica bead as the supporting matrix. Bayberry tannin-immobilized mesoporous silica bead (BT-SiO2) Was characterized by powder X-ray diffraction to verify the crystallinity, field-emission scanning electron microscopy to observe the surface morphology, and surface area and porosity analyzer to measure the mesoporous porous structure. Subsequently, the adsorption experiments to Cr(III) were applied to evaluate the adsorption performances of BT-SiO2. It was found that the adsorption of Cr(III) onto BT-SiO2 was pH-dependent, and the maximum adsorption capacity was obtained in the pH range of 5.0-5.5. The adsorption capacity was 1.30 mmol g(-1) at 303 K and pH 5.5 when the initial concentration of Cr(III) was 2.0 mmol L-1. Based on proton nuclear magnetic resonance (HNMR) analyses, the adsorption mechanism of Cr(III) on BT-SiO2 was proved to be a chelating interaction. The adsorption kinetic data can be well described using pseudo-first-order model and the equilibrium data can be well fitted by the Langmuir isothermal model. Importantly, no bayberry tannin was leached out during the adsorption process and BT-SiO2 can simultaneously remove coexisting metal ions from aqueous solutions. In conclusion, this study provides a new strategy for the preparation of tannin-immobilized adsorbents that are highly effective in removal of heavy metals from aqueous solutions. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.

Keywords: Activated Carbons, Adsorption, Adsorption Capacity, Adsorption Mechanism, Aqueous Solutions, Bayberry Tannin, Chromium(III), Collagen Fiber, Cr(III), Derivatives, Equilibrium, Heavy Metals, Heavy-Metal Adsorption, Immobilization, Kinetic, Langmuir, Low-Cost Adsorbents, Mesoporous, Mesoporous Silica Bead, Metal Ions, Methylene-Blue, pH, Removal, Silica, Water, X-Ray, X-Ray Diffraction

? Besov, A.S., Krivova, N.A., Vorontsov, A.V., Zaeva, O.B., Kozlov, D.V., Vorozhtsov, A.B., Parmon, V.N., Sakovich, G.V., Komarov, V.F., Smirniotis, P.G. and Eisenreich, N. (2010), Air detoxification with nanosize TiO₂ aerosol tested on mice. Journal of Hazardous Materials, 173 (1-3), 40-46.

Full Text: 2010\J Haz Mat173, 40.pdf

Abstract: A method for fast air purification using high concentration aerosol of TiO2 nanoparticles is evaluated in a model chemical catastrophe involving toxic vapors of diisopropyl fluorophosphate (DFP). Mice are used as human model in a closed 100 dm(3) chamber. Exposure of mice to 37 ppm of DFP vapor for 15 min resulted in acute poisoning. Spraying TiO2 aerosol in 2 min after the start of exposure to DFP vapors resulted in quick removal of DFP vapors from the chamber’s air. Animals did not show signs of poisoning after the decontamination experiment and exposure to TiO2 aerosol alone. Reactive oxygen species (ROS) and antioxidant activity (AOA) of mice blood plasma were measured for animals exposed to sound of aerosol generator, DFP vapors,TiO2 aerosol and DFP vapors + TiO2 aerosol. Reduced ROS and increased AOA were found for mice exposure to sound, DFP and TiO2 aerosol. Exposure to DFP and decontamination with TiO2 nanoparticles resulted in decreased AOA in 48 h following the exposure. The results suggest that application of TiO2 aerosol is a powerful method of air purification from toxic hydrolysable compounds with moderate health aftermaths and requires further study and optimization. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Anti-Terrorism, Chemiluminescence, Compounds, CWA, Decomposition, Dimethyl Methylphosphonate, Exposure, FTIR Spectroscopy, Nanoparticles, Photocatalytic Oxidation, Photodegradation, Reactive Oxygen Species, Removal, Size, TiO₂, Titanium-Dioxide Nanoparticles

? Shu, Y.H., Li, L.S., Zhang, Q.Y. and Wu, H.H. (2010), Equilibrium, kinetics and thermodynamic studies for sorption of chlorobenzenes on CTMAB modified bentonite and kaolinite. Journal of Hazardous Materials, 173 (1-3), 47-53.

Full Text: 2010\J Haz Mat173, 47.pdf

Abstract: The sorption of chlorobenzenes (CBs) by cetyltrimethylammonium bromide (CTMAB) modified bentonite and kaolinite was investigated. The sorption isotherms for CBs were nearly linear, suggesting that sorption could be described by a distribution process. The distribution coefficient (K-d) was primarily affected by the amount of sorbed surfactant. The organic carbon normalized sorption coefficient (K-oc), however, was particularly dependent on arrangement of the surfactant cations. The K-d of CBs was larger for CTMAB-bentonites than that for CTMAB-kaolinites, while the case for K-oc was opposite. Thus, the clay mineral structure and morphology had a considerable influence on the surfactant arrangement, which was responsible for the partitioning of CBs. The sorption of CBs onto both CTMAB-bentonites and CTMAB-kaolinites followed pseudo-second-order kinetics. The intra-particle diffusion model for sorption was also investigated and compared to identify sorption mechanism. The sorption of CBs both on CTMAB-bentonites and CTMAB-kaolinites was exothermic in nature and accompanied by an increase in entropy and a decrease in Gibbs energy in the temperature range of 15-35ºC. The results indicated that CBs strongly interacted with CTMAB modified bentonite and kaolinite. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Bentonite, Bromide, Carbon, CBS, Cetyltrimethylammonium Bromide, Chlorobenzenes, Clay, Clay Mineral, Diffusion, Diffusion Model, Distribution, Distribution Coefficient, Energy, Entropy, Equilibrium, Exothermic, Intra-Particle Diffusion, Intraparticle Diffusion, Intraparticle Diffusion Model, Isotherms, K-Oc, Kaolinite, Kinetics, Mechanism, Model, Modified, Modified Bentonite and Kaolinite, Morphology, Organic, Organic Carbon, Phenanthrene, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-Second-Order, Pseudo-Second-Order Kinetics, Rights, Sediments, Sequestration, Soils, Sorption, Sorption Isotherms, Sorption Mechanism, Structure, Surfactant, Surfactant Sorption, Temperature, Thermodynamic, Thermodynamic Studies, Water

? Li, S.Z. and Wu, P.X. (2010), Characterization of sodium dodecyl sulfate modified iron pillared montmorillonite and its application for the removal of aqueous Cu(II) and Co(II). Journal of Hazardous Materials,