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184 (1-3), 765-774.

Full Text: 2010\J Haz Mat184, 765.pdf

Abstract: Reports are available on silver binding capacity of some microorganisms. However, reports on the equilibrium studies on biosorption of silver by macrofungi are seldom known. The present study was carried out in a batch system using dead biomass of macrofungus Pleurotus platypus for the sorption of Ag(I). P. platypus exhibited the highest silver uptake of 46.7 mg g(-1) of biomass at pH 6.0 in the presence of 200 mg L-1 Ag(I) at 20 degrees C. Kinetic studies based on fractional power, zero order, first order, pseudo-first order, Elovich, second order and pseudo-second order rate expressions have been carried out. The results showed a very good compliance with the pseudo-first order model. The experimental data were analyzed using two parameter isotherms (Langmuir. Freundlich, Dubinin-Radushkevich, Temkin and Halsey), three parameter isotherms (Redlich-Peterson, Sips, Khan, Koble-Corrigan, Hill, Toth. Radke-Prausmitz, Jossens, Langmuir-Freundlich), four parameter isotherms (Weber-van Vliet, Fritz-Schlunder, Baudu) and five parameter isotherm (Fritz-Schlunder). Thermodynamic parameters of the biosorption (Delta G. Delta H and Delta S) were also determined. The present study confirmed that macrofungus P. platypus may be used as a cost effective efficient biosorbent for the removal of Ag(1) ions from aqueous solution. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Ag(I), Agaricus-Bisporus, Batch, Batch System, Biomass, Biosorbent, Biosorption, Capacity, Cost, Data, Dubinin-Radushkevich, Elovich, Equilibrium, Freundlich, Fundamental Properties, Granular Activated Carbon, Intraparticle Diffusion, Isotherm, Isotherm Models, Isotherms, Kinetic, Kinetic Studies, Kinetics, Langmuir, Macrofungus, Microorganisms, Model, Organic Solutes, pH, Pleurotus Platypus, Precious Metals, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second-Order, Removal, Reports, Saccharomyces-Cerevisiae, Second-Order, Silver, Sorption, System, Temkin, Thermodynamic, Thermodynamic Parameters, Uptake, Waste-Water

? Gupta, K., Maity, A. and Ghosh, U.C. (2010), Manganese associated nanoparticles agglomerate of iron(III) oxide: Synthesis, characterization and arsenic(III) sorption behavior with mechanism. Journal of Hazardous Materials, 184 (1-3), 832-842.

Full Text: 2010\J Haz Mat184, 832.pdf

Abstract: Three samples of manganese associated hydrous iron(III) oxide (MNHFO), prepared by incinerating metal hydroxide precipitate at T (+/- 5)=90, 300 and 600 degrees C, showed increase of crystalline nature in XRD patterns with decreasing As(III) removal percentages. TEM images showed the increase of crystallinity from sample-1 (MNHFO-1) to sapmple-3 (MNHFO-3). Dimensions (nm) of particles estimated were 5.0.7.0 and 97.5. Optimization of pH indicated that MNHFO-1 could remove aqueous As(III) efficiently at pH between 3.0 and 7.0. Kinetic and equilibrium data of reactions under the experimental conditions described the pseudo-second order and the Langmuir isotherm equations very well, respectively. The Langmuir capacity (q(m)) estimated was 691.04 mmol kg(-1). The values of enthalpy. Gibb’s free energy and entropy changes (Delta H-0 = +23.23 kJ mol(-1), Delta G(0) = -3.43 to -7.20 kJ mol(-1) at T=283-323 K. Delta S-0 = +0.094 kJ mol(-1) K-1) suggested that the reaction was endothermic, spontaneous and took place with increasing entropy. The As(III) sorbed by MNHFO-1 underwent surface oxidation to As(V), and evidences appeared from the XPS and FTIR investigations. MNHFO-1 packed column (internal diameter: 1.0 cm, height: 3.7 cm) filtered 11.5 dm(3) groundwater (105 mu g As dm(-3)) with reducing arsenic concentration to <= 10 mu g dm(-3). (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Arsenate Adsorption, Arsenic, Arsenic(III), As(III), As(V), Capacity, Characterization, Data, Equilibrium, Fe, FTIR, Iron-Oxide, Isotherm, Kinetic, Langmuir, Langmuir Isotherm, Manganese, Manganese Associated Iron(III) Oxide, Mechanism, Nanocrystals, Nanoparticle, Nanoparticles, Optimization, Oxidation, Oxide, pH, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second-Order, Removal, Sorption, Synthesis, TEM, Water, XPS, XRD

? Poinern, G.E.J., Ghosh, M.K., Ng, Y.J., Issa, T.B., Anand, S. and Singh, P. (2011), Defluoridation behavior of nanostructured hydroxyapatite synthesized through an ultrasonic and microwave combined technique. Journal of Hazardous Materials, 185 (1), 29-37.

Full Text: 2011\J Haz Mat185, 29.pdf

Abstract: The absorption performance of a nano-structured hydroxyapatite produced from a combined ultrasonic and microwave technique was examined for the removal of fluoride from contaminated water. The effect of physical and chemical parameters such as initial pH, contact time, initial fluoride concentration and temperature were investigated. The results indicated that the equilibrium adsorption data followed both the Langmuir and Freundlich isotherms, with a maximum mono layer adsorption capacity of 5.5 mg/g at 298 K. In addition, the kinetic studies have shown that the fluor de adsorption data followed a pseudo-second order model and that the intra-particle diffusion process played a significant role in determining the rate. The thermodynamic analysis also established that the adsorption process was endothermic and spontaneous. The initial and final fluoride loaded nano-hydroxyapatite samples were characterized using FESEM, TEM, XRD, FTIR and XPS methods. The analysis revealed that structural changes to the adsorbent had taken place. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption, Aqueous-Solutions, Composite, Defluoridation, Equilibrium, Fluoride, Fluoride Removal, Freundlich, FTIR, Hydroxyapatite, Isotherms, Kinetic, Langmuir, Microwaves, Nanohydroxyapatite, pH, Sorption, Synthetic Hydroxyapatite, Temperature, Thermodynamic, Ultrasonic Irradiation, XPS

? Feng, N.C., Guo, X.Y., Liang, S., Zhu, Y.S. and Liu, J.P. (2011), Biosorption of heavy metals from aqueous solutions by chemically modified orange peel. Journal of Hazardous Materials, 185 (1), 49-54.

Full Text: 2011\J Haz Mat185, 49.pdf

Abstract: Equilibrium, thermodynamic and kinetic studies were carried out for the biosorption of Pb2+, Cd2+ and Ni2+ ions from aqueous solution using the grafted copolymerization-modified orange peel (OPAA). Langmuir and Freundlich isotherm models were applied to describe the biosorption of the metal ions onto OPAA. The influences of pH and contact time of solution on the biosorption were studied. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. According to the Langmuir equation, the maximum uptake capacities for Pb2+, Cd2+ and Ni2+ ions were 476 1,293.3 and 162.6 mg g-1, respectively. Compared with the unmodified orange peel, the biosorption capacity of the modified biomass increased 4.2-, 4.6- and 16.5-fold for Pb2+, Cd2+ and Ni2+, respectively. The kinetics for Pb2+, Cd2+ and Ni2+ ions biosorption followed the pseudo-second-order kinetics. The free energy changes (ΔGº) for Pb2+, Cd2+ and Ni2+ ions biosorption process were found to be -3.77, -4.99 and -4.22 kJ mol-1, respectively, which indicates the spontaneous nature of biosorption process. FTIR demonstrated that carboxyl and hydroxyl groups were involved in the biosorption of the metal ions. Desorption of Pb2+, Cd2+ and Ni2+ ions from the biosorbent was effectively achieved in a 0.05 mol L-1 HCl solution. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorbents, Adsorption, Aqueous Solution, Biomass, Biosorbent, Biosorption, Coir Pith, Desorption, Equilibrium, Freundlich, Freundlich Isotherm, FTIR, Heavy Metal Ions, Heavy Metals, Ion-Exchange, Isotherm, Isotherms, Kinetic, Kinetics, Langmuir, Lead, Modified Orange Peel, pH, Removal, Thermodynamic, Thermodynamics, Waste-Water

? Su, J., Huang, H.G., Jin, X.Y., Lu, X.Q. and Chen, Z.L. (2011), Synthesis, characterization and kinetic of a surfactant-modified bentonite used to remove As(III) and As(V) from aqueous solution. Journal of Hazardous Materials, 185 (1), 63-70.

Full Text: 2011\J Haz Mat185, 63.pdf

Abstract: In this study, organobentonites were prepared by modification of bentonite with various cationic surfactants, and were used to remove As(V) and As(III) from aqueous solution. The results showed that the adsorption capacities of bentonite modified with octadecy, benzyl dimethyl ammonium (SMB3) were 0.288 mg/g for As(V) and 0.102 mg/g for As(III), which were much higher compared to 0.043 and 0.036 mg/g of un-modified bentonite (UB). The adsorption kinetics were fitted well with the pseudo-second-order model with rate constants of 46.7 x 10(-3) g/mg h for As(V) and 3.1 x 10(-3) g/mg h for As(III), respectively. The maximum adsorption capacity of As(V) derived from the Langmuir equation reached as high as 1.48 mg/g, while the maximum adsorption capacity of As(III) was 0.82 mg/g. The adsorption of As(V) and As(III) was strongly dependent on solution pH. Addition of anions did not impact on As(III) adsorption, while they clearly suppressed adsorption of As(V). In addition, this study also showed that desorbed rates were 74.61% for As(V) and 30.32% for As(III), respectively, after regeneration of SMB3 in 0.1 M HCl solution. Furthermore, in order to interpret the proposed absorption mechanism, both SMB3 and UB were extensively characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analyses. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Kinetics, Ammonium, Aqueous Solution, Arsenic Adsorption, As(III), As(V), Characterization, Clay, Cr(VI), Electron Microscopy, FTIR, Ionic-Strength, Kaolinite, Kinetic, Kinetics, Langmuir, Mechanism, Modified Bentonite, Modified Carbon-Black, Modified Zeolite, Montmorillonite, pH, Sorption, Surfactant, Water

? Chen, Y.H. and Chen, Y.D. (2011), Kinetic study of Cu(II) adsorption on nanosized BaTiO3 and SrTiO3 photocatalysts. Journal of Hazardous Materials, 185 (1), 168-173.

Full Text: 2011\J Haz Mat185, 168.pdf

Abstract: In this study, nanoparticles with perovskite structure (nano-SrTiO(3) and nano-BaTiO(3)) were synthesized via a co-precipitation method, and their photocatalytic and adsorption characteristics were investigated. Both of them exhibited some photocatalytic activity and possessed a high adsorption capacity for copper ions. Further, the pseudo-first-order model was found to be more suitable to fit the experimental data. Moreover, it suggested that the Langmuir model was more adequate in simulating the adsorption isotherm. The maximum adsorption capacity was 370.4 mg/g and 200.0 mg/g for nano-SrTiO(3) and nano-BaTiO(3), respectively. The negative apparent free energy confirmed that the Cu(2+) adsorption onto the nano-photocatalysts was a spontaneous process. The underlying mechanism of adsorption of Cu(II) onto nano-perovskites could be due to the ion exchange and surface complexation. From the results. SrTiO(3) and BaTiO(3) nanoparticles may be an effective material for Cu(2+) removal and, together with its photocatalytic activity, may be suitable for environmental remediation applications. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Isotherm, Aqueous-Solutions, Capacity, Co-Precipitation, Complexation, Copper, Coprecipitation, Copyright, Cu(2+) Adsorption, Cu(2+) Removal, Cu(Ii), Cu(Ii) Adsorption, Degradation, Doped Srtio3, Energy, Environmental, Experimental, Hydrothermal Synthesis, Ion Exchange, Ions, Isotherm, Kinetic, Kinetic Study, Langmuir Model, Mechanism, Model, Nano-Batio(3), Nano-Srtio(3), Nanocrystals, Photocatalyst, Pseudo-First-Order, Remediation, Removal, Size, Sol-Gel, Temperature, Titanium-Dioxide

? Hu, X.J., Wang, J.S., Liu, Y.G., Li, X., Zeng, G.M., Bao, Z.L., Zeng, X.X., Chen, A.W. and Long, F. (2011), Adsorption of chromium (VI) by ethylenediamine-modified cross-linked magnetic chitosan resin: Isotherms, kinetics and thermodynamics. Journal of Hazardous Materials, 185 (1), 306-314.

Full Text: 2011\J Haz Mat185, 306.pdf

Abstract: The adsorption of chromium (VI) ions from aqueous solution by ethylenediamine-modified cross-linked magnetic chitosan resin (EMCMCR) was studied in a batch adsorption system. Chromium (VI) removal is pH dependent and the optimum adsorption was observed at pH 2.0. The adsorption rate was extremely fast and the equilibrium was established within 6-10 min. The adsorption data could be well interpreted by the Langmuir and Temkin model. The maximum adsorption capacities obtained from the Langmuir model are 51.813 mg g-1, 48.780 mg g-1 and 45.872 mg g(-1) at 293, 303 and 313 K, respectively. The adsorption process could be described by pseudo-second-order kinetic model. The intraparticle diffusion study revealed that film diffusion might be involved in the present case. Thermodynamic parameters revealed the feasibility, spontaneity and exothermic nature of adsorption. The sorbents were successfully regenerated using 0.1 N NaOH solutions. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorption, Aqueous Solution, Aqueous-Solution, Beads, Biosorption, Chromium, Chromium(VI), Cu(II) Ions, EMCMCR, Equilibrium, Equilibrium Isotherm, Heavy-Metal, Hexavalent Chromium, Isotherms, Kinetic, Kinetic Model, Kinetics, Langmuir, pH, Removal, Resin, Sorption, Thermodynamic, Thermodynamic Parameters, Thermodynamics, VI

? Falciglia, P.P., Giustra, M.G. and Vagliasindi, F.G.A. (2011), Low-temperature thermal desorption of diesel polluted soil: Influence of temperature and soil texture on contaminant removal kinetics. Journal of Hazardous Materials, 185 (1), 392-400.

Full Text: 2011\J Haz Mat185, 392.pdf

Abstract: Five soil size aggregate fractions, corresponding to coarse (500-840 mu m), medium (200-350 mu m), fine (75-200 mu m) sand, silt (10-75 mu m) and clay (<4 mu m), were artificially contaminated with diesel, and thermally treated using a laboratory scale apparatus to investigate the effect of soil texture on contaminant adsorption and removal. Ex situ thermal process was simulated using helium as the carrier gas at a flow rate of 1.5 L min(-1), different temperatures (100-300 degrees C) and different treatment times (5-30 min). The amount of contaminant adsorbed on the soil and the residual amount after thermal treatment was determined by gas chromatography. Results showed that adsorption phenomena and desorption efficiency were affected by the soil texture and that temperature and time of treatment were key factors in remedial process. A temperature of 175 degrees C is sufficient to remedy diesel polluted sandy and silty soils, whereas a higher temperature (250 degrees C) is needed for clays. Thermal desorption of diesel polluted soil was shown to be governed by first-order kinetics. Results are of practical interest and may be used in scaling-up and designing desorption systems for preliminary cost and optimal condition assessment. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Assessment, Biodegradation, Capacity, Clay, Decontamination, Desorption, Diesel Fuel, First Order, Fuel, Gas, Hydrocarbons, Interest, Kinetics, Natural Attenuation, Oil, Ozonation, Remediation, Removal, Soil, Soil Remediation, Soil Texture, Thermal Desorption, Treatment

? Montazer-Rahmati, M.M., Rabbani, P., Abdolali, A. and Keshtkar, A.R. (2011), Kinetics and equilibrium studies on biosorption of cadmium, lead, and nickel ions from aqueous solutions by intact and chemically modified brown algae. Journal of Hazardous Materials, 185 (1), 401-407.

Full Text: 2011\J Haz Mat185, 401.pdf

Abstract: The present study deals with the evaluation of biosorptive removal of Cd (II), Ni (II) and Pb (II) ions by both intact and pre-treated brown marine algae: Cystoseira indica, Sargassum glaucescens, Nizimuddinia zanardini and Padina australis treated with formaldehyde (FA), glutaraldehyde (GA), polyethylene imine (PEI), calcium chloride (CaCl2) and hydrochloric acid (HCl). Batch shaking adsorption experiments were performed in order to examine the effects of pH, contact time, biomass concentration, biomass treatment and initial metal concentration on the removal process. The optimum sorption conditions for each heavy metal are presented. One-way ANOVA and one sample t-tests were performed on experimental data to evaluate the statistical significance of biosorption capacities after five cycles of sorption and desorption. The equilibrium experimental data were tested using the most common isotherms. The results are best fitted by the Freundlich model among two-parameter models and the Toth, Khan and Radke-Prausnitz models among three-parameter isotherm models for Cd (II), Ni (II) and Pb (II), respectively. The kinetic data were fitted by models including pseudo-first-order and pseudo-second-order. From the results obtained, the pseudo-second-order kinetic model best describes the biosorption of cadmium, nickel and lead ions. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Batch, Biosorption, Brown Algae, Cadmium, Ceramium-Virgatum, Chloride, Chromium, Copper, Desorption, Equilibrium, FA, Freundlich, Heavy Metals, Isotherm, Isotherms, Kinetic, Kinetic Model, Kinetics, Marine-Algae, Metals, Models, Modified Biomass, Nickel, Pb, Pb(II), pH, Radke-Prausnitz, Sargassum, Sorption, Toth, Waste Biomass

? Stojakovic, D., Hrenovic, J., Mazaj, M. and Rajic, N. (2011), On the zinc sorption by the Serbian natural clinoptilolite and the disinfecting ability and phosphate affinity of the exhausted sorbent. Journal of Hazardous Materials, 185 (1), 408-415.

Full Text: 2011\J Haz Mat185, 408.pdf

Abstract: The Serbian natural zeolite is moderately effective in removing the zinc(II) ions from aqueous solutions. At 298 K the sorption capacity varies from 13 to 26% for the initial Zn(II) solution concentration of 100 and 600 mgZn dm-3, respectively. The sorption isotherm at 298-338 K is best represented by the Langmuir model and the sorption kinetics by the pseudo-second-order model. The sorption involves a combination of film diffusion, intra-particle diffusion, and a chemical cation-exchange between the Na+ ions of clinoptilolite and Zn2+ ions. The sorption was found to be endothermic and spontaneous in the 298-338 K range. The exhausted sorbent can remove phosphate ions and it exhibits an excellent antibacterial activity towards Acinetobacter junii. By dehydration at about 500ºC it transforms to a ZnO-containing product featuring nano-sized wurtzite ZnO particles widespread over the clinoptilolite surface. (C) 2010 Published by Elsevier B.V.

Keywords: Accumulating Bacteria, Adsorption, Antibacterial Activity, Aqueous-Solutions, Biosorption, Copper, Isotherm, Kinetics, Langmuir, Lead, Metal-Ions, Modified Zeolites, Nano-Zno, Phosphate Removal, Removal, Sludge, Sorption, Zeolite, Zinc Removal

? Chen, C.Y., Chang, J.C. and Chen, A.H. (2011), Competitive biosorption of azo dyes from aqueous solution on the templated crosslinked-chitosan nanoparticles. Journal of Hazardous Materials, 185 (1), 430-441.

Full Text: 2011\J Haz Mat185, 430.pdf

Abstract: The nanoparticles of templated crosslinked chitosan, ECH-RB5 and ECH-3R, were prepared through the imprinting process using Remazol Black 5 (RB5) and Remazol Brilliant Orange 3R (3R) dyes, respectively, as templates and ECH as a crosslinker. The nanoparticles exhibited significantly higher adsorption capacities of the dyes than other nanoparticles formed without a dye template and with three crosslinkers (ECH, GLA, and EGDE). The adsorption of the dyes on the nanoparticles was affected by the initial pH, dye concentration, and temperature. The results were in accordance with the second-order and the Langmuir adsorption models. Meanwhile, the E values of the dyes calculated using the Dubinnin-Radushkevich model revealed that the adsorption process may be due to the dual nature of the process, physisorption and chemisorption, and that adsorption was predominant in the chemisorption process. The adsorption processes in the nanoparticles were spontaneous and exothermic. Moreover, competition adsorption through analysis of the intraparticle diffusion model apparently favored the 3R dye more than the RB5 dye on the nanoparticles in mixture solution B. The nanoparticles for the adsorption of the dyes were regenerated efficiently through the alkaline solution and were then reused for dye removal. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.

Keywords: Acid Dye, Adsorption, Adsorption Behavior, Analysis, Azo Dye, Azo Dyes, Beads, Biosorption, Chitosan, Competition, Copyright, Diffusion, Dye Removal, Eosin-Y, Equilibria, Intraparticle Diffusion, Model, Model Anionic Dye, pH, RB5, Reactive Dye, Regeneration, Remazol Brilliant Orange 3R, Removal, Resin, Sorption, Templated Crosslinked-Chitosan Nanoparticle

? Humelnicu, D., Dinu, M.V. and Dragan, E.S. (2011), Adsorption characteristics of UO22+ and Th4+ ions from simulated radioactive solutions onto chitosan/clinoptilolite sorbents. Journal of Hazardous Materials, 185 (1), 447-455.

Full Text: 2011\J Haz Mat185, 447.pdf

Abstract: Adsorption features of UO22+ and Th4+ ions from simulated radioactive solutions onto a novel chitosan/clinoptilolite (CS/CPL) composite as beads have been investigated compared with chitosan cross-linked with epichlorohydrin. The effects of contact time, the initial metal ion concentration, sorbent mass and temperature on the adsorption capacity of the CS-based sorbents were investigated. The adsorption kinetics was well described by the pseudo-second order equat on, and the adsorption isotherms were better fitted by the Sips model. The maximum experimental adsorption capacities were 328.32 mg Th4+/g composite, and 408.62 mg UO22+/g composite. The overall adsorption tendency of CS/CPL composite toward UO22+ and Th4+ radiocations in the presence of Cu2+, Fe2+ and Al3+, under competitive conditions, followed the order: Cu2+ > UO22+ > Fe2+ >Al3+, and Cu2+ >Th4+ > Fe2+ > Al3+, respectively. The negative values of Gibbs free energy of adsorption indicated the spontaneity of the adsorption of radioactive ions on both the CS/CPL composite and the cross-linked CS. The desorption level of UO22+ from the composite CS/CPL, by using 0.1 M Na2CO3, was around 92%, and that of 1h4 ions, performed by 0.1 M HCl, was around 85%, both values being higher than the desorption level of radiocations from the cross-linked CS, which were 89% and 83%, respectively. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Isotherms, Adsorption Kinetics, Aqueous-Solutions, Chitosan, Chitosan, Clinoptilolite, Composite, Desorption, Isotherms, Kinetics, Natural-Zeolite, Nickel, Radiocations, Removal, Sorption, Sorption, Thermodynamic Parameters, Uranium, Uranyl Ions, Waste-Water

? Hu, J., Shao, D.D., Chen, C.L., Sheng, G.D., Ren, X.M. and Wang, X.K. (2011), Removal of 1-naphthylamine from aqueous solution by multiwall carbon nanotubes/iron oxides/cyclodextrin composite. Journal of Hazardous Materials, 185 (1), 463-471.

Full Text: 2011\J Haz Mat185, 463.pdf

Abstract: The adsorption of 1-naphthylamine on multiwall carbon nanotubes/iron oxides/beta-cyclodextrin composite (denoted by MWCNTs/iron oxides/CD) prepared by using plasma-induced grafting technique was investigated by batch technique under ambient conditions. The effect of contact time, pH, adsorbent content, temperature and initial 1-naphthylamine concentration, on 1-naphthylamine adsorption to MWCNTs/iron oxides/CD was examined. The adsorption of 1-naphthylamine on MWCNTs/iron oxides/CD was dependent on pH, adsorbent content, and temperature. The 1-napthylamien was adsorbed rapidly at the first 50 h, and thereafter attained the adsorption saturation at 80 h. The adsorption kinetic data were well described by the pseuso-second-order rate model. The adsorption isotherms were fitted by the Langmuir model better than by the Freundlich model. The maximum adsorption capacity of 1-naphthylamine was 200.0 mg/g. The adsorption thermodynamic parameters of standard enthalpy (Delta H(0)), standard entropy changes (Delta S(0)), and standard free energy (Delta G(0)) were calculated from temperature dependent adsorption isotherms. The values of Delta H(0) and Delta G(0) suggested that the adsorption of 1-naphthylamine on MWCNTs/iron oxides/CD was endothermic and spontaneous. The electron-donor-acceptor interaction, Hydrophobic interaction, and Lewis acid-base interaction may plar an important role in 1-naphthylamine adsorption. The results show that MWCNTs/iron oxides/CD is a promising magnetic nanomaterial for the preconcentration and separation of organic pollutants from aqueoi is solutions in environmental pollution cleanup. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: 1-Naphthylamine, Adsorbent, Adsorption, Adsorption, Adsorption Isotherms, Capacity, Cyclodextrin, Energy, Environmental, Isotherms, Kinetic, Kinetics, Langmuir Model, Manotubes, Mechanism, Methylene-Blue, Model, Mwcnts, Iron Oxides, Cd, pH, Phenol, Pollutants, Removal, Rice Husk, Sorption, Thermodynamic Parameter, Thermodynamic Parameters, Thermodynamics

? Zhou, Q., Gong, W.Q., Xie, C.X., Yang, D.J., Ling, X.Q., Yuan, X.A., Chen, S.H. and Liu, X.F. (2011), Removal of Neutral Red from aqueous solution by adsorption on spent cottonseed hull substrate. Journal of Hazardous Materials,



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