Personal Research Database

Full Text: 2010\J Haz Mat174, 424.pdf

Abstract: Microorganisms compete with other species by secreting antimicrobial compounds. The compact structure of aerobic granules was generally assumed to provide spatial isolation, resulting in the co-occurrence of diverse strains that have similar or dissimilar functions. No studies have investigated whether stable, mature aerobic granules can be formed with two mutually inhibitory strains. The strain Acinetobacter sp. 18 competes with Bacillus sphaericus 15 in a well-mixed environment, but can form stable and mature granules at 400 mg L-1 phenol by repeatedly replenishing fresh medium in a sequencing batch reactor. The supernatants collected from the 18 medium in its exponential-growth phase or from the 15+18 medium cultivated for 12 or 24 h significantly inhibited 15 growth. Addition of tightly bound extracellular polymeric substances (TBEPS) or loosely bound extracellular polymeric substances (LBEPS) extracted from 15+18 granules effectively suppressed the inhibitory effects of 18 on 15. The TBEPS or LBEPS physically separate strain 15 from 18 in the granule, and effectively adsorb the inhibitory substance(s) in the suspension. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Activated-Sludge, Adsorption, Aerobic Granules, Bacterial Strains, Batch, Biodegradation, Compounds, EPS, Granulation, Inhibition, Microbial Diversity, Phenol, Physical Isolation, Sequencing Batch Reactor, Soil, Waste-Water

? Asadullah, M., Asaduzzaman, M., Kabir, M.S., Mostofa, M.G. and Miyazawa, T. (2010), Chemical and structural evaluation of activated carbon prepared from jute sticks for Brilliant Green dye removal from aqueous solution. Journal of Hazardous Materials, 174 (1-3), 437-443.

Full Text: 2010\J Haz Mat174, 437.pdf

Abstract: Activated carbons have been prepared from jute sticks by chemical activation using ZnCl2 and physical activation using steam for the removal of Brilliant Green dye from aqueous solution. The activated carbons and charcoal prepared from jute sticks were characterized by evaluating the surface chemistry, structural features and surface morphology. The maximum BET surface area was obtained to be 2304 m(2)/g for chemical activated carbon (ACC) while it is 730 and 80 m(2)/g for steam activated carbon (ACS) and charcoal, respectively. The FT-IR spectra exhibited that the pyrolysis and steam activation of jute sticks resulted in the release of aliphatic and O-containing functional groups by thermal effect. However, the release of functional groups is the effect of chemical reaction in the ZnCl2 activation process. A honeycomb-type carbon structure in ACC was formed as observed on SEM images. Although charcoal and ACC were prepared at 500 degrees C the ACC exhibited much lower Raman sensitivity due to the formation of condensed aromatic ring systems. Due to high surface area and high porous structure with abundance of functional groups, the ACC adsorbed dye molecules with much higher efficiency than those of ACS and charcoal. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Activated Carbons, Adsorption, Adsorption, Biomass, Carbon Structure, Char Structure, Chemical Activation, Dye, Evaluation, FTIR, Gasification, Kinetics, Molecules, Pyrolysis, Reactive Dyes, Removal, SEM, Steam, Surface Chemistry, Temperature, Victorian Brown-Coal

? Khan, A.A., Muthukrishnan, M. and Guha, B.K. (2010), Sorption and transport modeling of hexavalent chromium on soil media. Journal of Hazardous Materials, 174 (1-3), 444-454.

Full Text: 2010\J Haz Mat174, 444.pdf

Abstract: Chromium-soil adsorption system exhibited both Langmuir and Freundlich isotherm models fit to the sorption data in the studied range of concentration. However the model fit was much better for Freundlich isotherm, this was primarily due to low adsorptive capacity of the soil, 1 In is equal to about 1.08 which is quite close to 1.0, indicating low adsorptive capacity of the soil for chromium(VI) system and the Q(max) was observed very low in range of 0.196-0.220 mg Cr(VI)/g of soil. The initial concentration of Cr(VI) in the solution remarkably influenced the equilibrium Cr(VI) uptake on soil sorption process. The model simulated results for the natural redemption of the soil show the periodic movement of the chromium concentration front ultimately reaching quite low concentration at the end of the cycles. In the case of inorganic chemicals, the absence of chemical decay makes the adsorption phenomena as the major contaminant removal mechanism where as for biodegradation the chemical depletion becomes a major factor in the transport of pollutant. Consequently, the concentration of contaminants reaching the ground water table becomes quite low. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Biodegradation, Chromium, Cr(VI), Dyes, Equilibrium, Freundlich, Freundlich Isotherm, Groundwater, In Situ Flushing, Isotherm, Isotherm Models, Langmuir, Langmuir And Freundlich Isotherm, Modeling, Remediation Technologies, Removal, Soil, Soil Contamination, Soil Remediation, Sorption, System, Water

? Vega, F.A., Andrade, M.L. and Covelo, E.F. (2010), Influence of soil properties on the sorption and retention of cadmium, copper and lead, separately and together, by 20 soil horizons: Comparison of linear regression and tree regression analyses. Journal of Hazardous Materials, 174 (1-3), 522-533.

Full Text: 2010\J Haz Mat174, 522.pdf

Abstract: in this paper we compare linear regression with tree regression for analysis of the influence of soil properties on the sorption and retention of added Cd, Cu and Pb by 20 soil horizons typical of cropped soils in Galicia (N.W. Spain); our measure of sorption/retention capacity was K-r, a recently introduced adimensional parameter. Sorption and retention of Cd was depressed by the presence of Cu and Pb. The soil parameters that were most associated, overall, with differences in Cd, Cu and Pb sorption and retention were cation exchange capacity (CEC), pH and Mn oxides’ content. Tree regression, which can take into account variation on both global and local scales. afforded better-fitting models than linear regression, which only reflects global tendencies; but for coherent interpretability of tree regression results it is just as important to avoid overfitting as in the case of linear regression. (C) 2009 Published by Elsevier B.V.

Keywords: Analysis, Cadmium, Capacity, Cation Exchange, Classification and Regression Trees, Competitive Adsorption, Constituents, Copper, Desorption, Desorption, Heavy Metal, Heavy-Metals, Lead, Nickel, Organic-Matter, Parameter, pH, Retention, Soil, Soil Characteristics, Soils, Sorption, Spain, Zinc

? Çelik, Z., Gülfen, M. and Aydin, A.O. (2010), Synthesis of a novel dithiooxamide-formaldehyde resin and its application to the adsorption and separation of silver ions. Journal of Hazardous Materials, 174 (1-3), 556-562.

Full Text: 2010\J Haz Mat174, 556.pdf

Abstract: In this study, a new chelating resin of dithiooxamide (rubeanic acid)-formaldehyde (DTOF) has been synthesized by the reaction of dithiooxamide and formaldehyde. Also a well-known chelating resin of thiourea (thiooxamide)-formaldehyde(TUF) has been prepared by the reaction of thiourea and formaldehyde. DTOF and TUF chelating resins were used in the adsorption, separation and concentration of silver ions by batch and column techniques. These resins were characterized using FTIR and elemental analysis. It was found that DTOF resin has silver adsorption capacity of 3333.3 mg g(-1) or 30.86 mmolg g(-1) and TUF resin has the capacity of 1428.6 mg g(-1) or 13.22 mmol g(-1). DTOF resin showed more affinity to silver ions according to Cu(II), Zn(II), Ni(II) and Co(II) base metal ions than TUF resin. It was also demonstrated that DTOF resin can be used in the separation and concentration of silver ions. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Absorption Spectrometric Determinations, Adsorption, Adsorption Capacity, Analysis, Aqueous-Solutions, Base-Metal Ions, Batch, Chelating Resin, Co(II), Copper(II), Cu(II), Dithiooxamide Acid-Formaldehyde Resin, Environmental-Samples, FTIR, Metal Ions, MFT Chelating Resin, Preconcentration, Recovery, Separation, Silver Ions, Solid-Phase Extraction, Thiourea-Formaldehyde, Thiourea-Formaldehyde Resin

? Ding, C.L., Yang, X., Liu, W., Chang, Y.J. and Shang, C.I. (2010), Removal of natural organic matter using surfactant-modified iron oxide-coated sand. Journal of Hazardous Materials, 174 (1-3), 567-572.

Full Text: 2010\J Haz Mat174, 567.pdf

Abstract: Iron oxide-coated sand (IOCS) was modified with hexadecyltrimethyl ammonium (HDTMA) and tested as an adsorbent for the removal of natural organic matter (NOM) from water. The modification did not change the physical properties of the IOCS but coated HDTMA onto its surface. The HDTMA-modified IOCS displayed a faster initial NOM adsorption and substantially higher capacity than the unmodified IOCS over a wide pH range in both batch and column adsorption. The enhancement was more pronounced at higher pH. Compared to unmodified IOCS, the HDTMA-modified IOCS removed more hydrophobic and larger NOM molecules and its NOM adsorption was less sensitive to the changes in ionic strength. The adsorption capacity of the modified IOCS was regenerated in-situ with NaOH solution and ex-situ with HDTMA solution. HDTMA-modified IOCS adsorption may be a promising alternative technology for NOM removal. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Acid, Adsorbent, Adsorption, Adsorption, Adsorption Capacity, Alternative, Ammonium, Aquatic Humic Substances, Batch, Capacity, Changes, Coated, Column, Desorption, Filtration, In Situ, Interfaces, Ionic Strength, Iron, Iron Oxide Coated Sand, Iron Oxide-Coated Sand, Modification, Modified, Modified Zeolite, NaOH, Natural, Natural Organic Matter, Nom, Organic, Organic Matter, pH, Physical, Range, Removal, Rights, Sand, Solution, Sorption, Strength, Surface, Surfactants, Technology, Water

? Yilmaz, E., Memon, S. and Yilmaz, M. (2010), Removal of direct azo dyes and aromatic amines from aqueous solutions using two beta-cyclodextrin-based polymers. Journal of Hazardous Materials, 174 (1-3), 592-597.

Full Text: 2010\J Haz Mat174, 592.pdf

Abstract: Two beta-cyclodextrin (beta-CD)-based polymers were synthesized using 4,4’-methylene-bis-phenyldiisocyanate (MDI) or hexamethylenediisocyanate (HMDI) as a cross linking agent in dimethylformamide and used as sorbents for the removal of azo dyes (Evans Blue and Chicago Sky Blue), as well as aromatic amines (benzidine. p-chloroaniline and alpha-naphthalamine) from aqueous solutions. The sorption experiments were carried out by using batch-wise procedure involving the determination of pH effect, sorbate concentration and contact time. Moreover, from the equation isotherms such as Langmuir and Freundlich were successfully applied to model the experimental data. From the results polymer 2 was found to be a better sorbent for both azo dyes and the aromatic amines as compared to polymer I as proved by Langmuir isotherm model. The proposed sorption mechanism involved several kinds of interactions: physical adsorption, hydrogen bonding and formation of an inclusion complex due to the beta-CD molecules through host-guest interactions. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Aqueous Solutions, Aromatic Amines, Beta-Cyclodextrin, Carcinogens, Complex, Contact Time, Derivatives, Direct Azo Dye, Dyes, Freundlich, Isotherm, Isotherms, Langmuir, Langmuir Isotherm, Molecules, Mutagenicity, pH, Polymers, Polysaccharides, Removal, Solid-Phase Extraction, Solid-Phase Extraction, Sorbent, Sorbents, Sorption, Sorption, Sorption Mechanism, Starch-Based Polymers, Waste-Water

? Chen, K.T., Lu, C.S., Chang, T.H., Lai, Y.Y., Chang, T.H., Wu, C.W. and Chen, C.C. (2010), Comparison of photodegradative efficiencies and mechanisms of Victoria Blue R assisted by Nafion-coated and fluorinated TiO₂ photocatalysts. Journal of Hazardous Materials, 174 (1-3), 598-609.

Full Text: 2010\J Haz Mat174, 598.pdf

Abstract: The purposes of this research were to study the effects of two modified photocatalysts, Nafion-coated TiO₂ and fluorinated TiO₂, and photocatalytic degradation of Victoria Blue R in aqueous solution. Photocatalytic degradation of Victoria Blue R was accelerated by the modified photocatalysts. Bulk and surface characterizations of the resulting powders were carried out. Attachment of the anions to the TiO₂ surface using the Nafion-coated-TiO₂ possibly results in increased adsorption of the cationic dye, and the degradation rate is larger for the cationic dye. It was found that Victoria Blue R on the two illuminated TiO₂ surfaces underwent very different changes. To obtain a better understanding on the mechanistic details of this modified-TiO₂-assisted photodegradation of the Victoria Blue R dye with UV irradiation, a large number of intermediates of the process were separated, identified, and characterized by a high-performance liquid chtomatography-mass spectrometry technique. Several probable photodegradation pathways were proposed and discussed. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Decomposition, Degradation, Dye, Fluorinated TiO₂, High-Performance Liquid Chromatography-Mass Spectrometry, Irradiation, Leucomalachite Green, Malachite Green, Nafion-Coated TiO₂, Nanoparticles, Organic-Compounds, Perfluorinated Ionomer Membranes, Photocatalytic, Photocatalytic Degradation, Research, Surface Fluorination, Surfaces, TiO₂, UV, Victoria Blue R, Visible-Light

? Ajouyed, O., Hurel, C., Ammari, M., Ben Allal, L. and Marmier, N. (2010), Sorption of Cr(VI) onto natural iron and aluminum (oxy)hydroxides: Effects of pH, ionic strength and initial concentration. Journal of Hazardous Materials, 174 (1-3), 616-622.

Full Text: 2010\J Haz Mat174, 616.pdf

Abstract: The aim of this work is to study the performances of removal of hexavalent chromium from aqueous solution by three different oxy-hydroxides: hematite, goethite and alpha-alumina. Batch experiments were conducted to measure the effects on adsorption of Cr(VI) of different parameters such as pH of the medium, ionic strength, and initial concentration. Results showed that the adsorption of Cr(VI) depends strongly on the pH, but is independent of ionic strength for hematite and goethite. For a-alumina, adsorption is strongly dependent on pH values and ionic strength. Equilibrium studies showed that Cr(VI) had a high affinity in an acidic medium, but decreased as solution pH increased. Equilibrium isotherms were measured experimentally. Results were analyzed by the Langmuir and Freundlich equations using linearized correlation coefficient at room temperature. The characteristic parameters for each isotherm have been determined. Langmuir equation was found to fit the equilibrium data for Cr(VI) adsorption. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption, Adsorption Isotherm, Aqueous-Solutions, Batch Experiments, Chromate, Chromium, Chromium(VI), Cr(VI), Cr(VI) Adsorption, Equilibrium, Freundlich, Goethite, Isotherm, Isotherms, Langmuir, Oxide, Oxy-Hydroxides, pH, Redox, Removal, Sediment, Sorption, Wastewaters, Water Interface

? Singh, R., Chadetrik, R., Kumar, R., Bishnoi, K., Bhatia, D., Kumar, A., Bishnoi, N.R. and Singh, N. (2010), Biosorption optimization of Lead(II), cadmium(II) and copper(II) using response surface methodology and applicability in isotherms and thermodynamics modeling. Journal of Hazardous Materials, 174 (1-3), 623-634.

Full Text: 2010\J Haz Mat174, 623.pdf

Abstract: The present study was carried out to optimize the various environmental conditions for biosorption of Pb(II), Cd(II) and Cu(II) by investigating as a function of the initial metal ion concentration, temperature, biosorbent loading and pH using Trichoderma viride as adsorbent. Biosorption of ions from aqueous solution was optimized in a batch system using response surface methodology. The values of R-2 0.9716, 0.9699 and 0.9982 for Pb(II), Cd(II) and Cu(II) ions, respectively, indicated the validity of the model. The thermodynamic properties Delta G degrees, Delta H degrees, Delta E degrees and Delta S degrees by the metal ions for biosorption were analyzed using the equilibrium constant value obtained from experimental data at different temperatures. The results showed that biosorption of Pb(II) ions by T viride adsorbent is more endothermic and spontaneous. The study was attempted to offer a better understating of representative biosorption isotherms and thermodynamics with special focuses on binding mechanism for biosorption using the FTIR spectroscopy. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Aqueous-Solution, Batch, Biosorption, Cd(II), Chromium(Vi), Copper(II), Cu(II), Equilibrium, FTIR, Heavy Metals, Heavy-Metals, Ions, Isotherms, Metal Ions, Modeling, Pb(II), pH, Removal, Response Surface Methodology, Sawdust, Sulfonic-Acid, System, Thermodynamic, Thermodynamics, Trichoderma Viride, Waste-Water

? Santana, S.A.A., Vieira, A.P., da Silva, E.C., Melo, J.C.P. and Airoldi, C. (2010), Immobilization of ethylenesulfide on babassu coconut epicarp and mesocarp for divalent cation sorption. Journal of Hazardous Materials, 174 (1-3), 714-719.

Full Text: 2010\J Haz Mat174, 714.pdf

Abstract: A new synthetic methodology route consisted in reacting the natural babassu coconut mesocarp (BCM) and babassu coconut epicarp (BCE) with ethylenesufide, for adding basic sulfur centers in pendant chains that possess high potential activity for coordinating divalent cations from aqueous solution. All biomaterials were characterized by elemental analysis, infrared (IR). C-13 NMR and thermogravimetry. The sulfur elemental analysis gave 2.00±0.05 and 8.67±0.01% for BCES and BCMS, which correspond to 0.60±0.01 and 2.71±0.01 mmol of this element per each gram of BCE and BCM, to confer a degree of functionalization of 20.2±0.07 and 86.7±0.01 mg g(-1). This synthesis enabled from IR weak SH band at 2544 cm^-1 due to the incorporation of the reagent into the structure. The basic centers favor copper sorption with increasing pH from 2 to 6 observed by a batchwise methodology and the data obtained from the chosen pH 6 were adjusted to Freundlich and Langmuir models, favoring fit for the latter equation. The kinetics of sorption was established at 30 min for both biopolymers with a pseudo-second-order model. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Analysis, Aqueous Solution, Aqueous-Solution, Babassu Coconut, Biomaterials, Biopolymers, C-13, Cation, Cation Sorption, Copper, Copper(II), Data, Divalent Cations, Ethylenesulfide, Fly-Ash, Freundlich, Heavy-Metal Ions, Immobilization, Industry Waste, IR, Kinetics, Langmuir, Lignocellulosic, Methodology, Model, Models, Natural, NMR, pH, Potential, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Removal, Rice Husk, Rights, Route, Solution, Sorption, Structure, Sulfur, Synthesis, Thermogravimetry, Waste-Water

? Tan, G.Q., Yuan, H.Y., Liu, Y. and Xiao, D. (2010), Removal of lead from aqueous solution with native and chemically modified corncobs. Journal of Hazardous Materials, 174 (1-3), 740-745.

Full Text: 2010\J Haz Mat174, 740.pdf

Abstract: In this study, corncobs biomass was utilized as an adsorbent to remove Pb(II) from aqueous solution. The adsorption behavior of Pb(II) was studied under different conditions, including solution pH, contact time and metal concentration. Ground corncobs were modified with CH₃OH and NaOH to investigate the effect of chemical modification on Pb(II) binding capacity. Results showed that Pb(II) binding on the biomass is pH-dependent and the kinetics can be well described by the Lagergren-second-order model. The maximum Pb(II) binding capacity q_max calculated from Langmuir isotherm was 0.0783 mmol/g. After base hydrolysis of the biomass. Pb(II) binding capacity increased from 0.0783 to 0.2095 mmol/g (about 43.4 mg Pb/g). However, Pb(II) binding capacity on the esterified corncobs decreased greatly from 0.0783 to 0.0381 mmol/g. Fourier transform infrared spectroscopy (FTIR) analysis showed that hydroxyl and carboxylic (COO-) groups on the biomass play an important role in Pb(II) binding process. The X-ray photoelectron spectroscopy (XPS) data further indicated that lead is adsorbed as Pb²⁺ and is attached to oxide groups on the biomass. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Behavior, Alfalfa Biomass, Analysis, Aqueous Solution, Behavior, Binding, Biomass, Capacity, Carboxylic, Chemical, Chemical Modification, Concentration, Coo, Corncobs, Data, Esterification, FTIR, Heavy-Metals, Hydrolysis, Infrared Spectroscopy, Isotherm, Kinetics, Langmuir, Langmuir Isotherm, Lead, Metal, Metal-Ions, Model, Modification, Modified, NaOH, Oxide, Pb(II), Pb²⁺, pH, pH-Dependent, Removal, Rice Husk, Rights, Role, Sawdust, Solution, Spectroscopy, Waste-Water, X-Ray, X-Ray Photoelectron Spectroscopy, X-Ray-Absorption, XPS

? Ijagbemi, C.O., Baek, M.H. and Kim, D.S. (2010), Adsorptive performance of un-calcined sodium exchanged and acid modified montmorillonite for Ni²⁺ removal: Equilibrium, kinetics, thermodynamics and regeneration studies. Journal of Hazardous Materials, 174 (1-3), 746-755.

Full Text: 2010\J Haz Mat174, 746.pdf

Abstract: The efficacy of un-calcined sodium exchanged (Na-MMT) and acid modified montmorillonite (A-MMT) has been investigated for adsorptive removal of Ni²⁺ from aqueous solution. Physico-chemical parameters such as pH, initial Ni²⁺ concentration, and equilibrium contact time were studied in a series of batch adsorption experiments. The equilibrium time of contact for both adsorbents was about 230 min. The Redlich-Peterson model best described the equilibrium sorption of Ni²⁺ onto Na-MMT and the Dubinin-Radushkevich model was the best model in predicting the equilibrium sorption of Ni²⁺ onto A-MMT. The kinetics of Ni²⁺ uptake by Na-MMT and A-MMT followed the pseudo second-order chemisorption mechanism. Sorptions of Ni²⁺ onto Na-MMT and A-MMT were spontaneous and endothermic. Regeneration was tried for several cycles with a view to recover the adsorbed Ni²⁺ and also to restore Na-MMT and A-MMT to their original states. The un-calcined Na-MMT and A-MMT have adsorptive potentials for removal of Ni²⁺ from aqueous bodies. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: A-Montmorillonite, Activated Carbon, Adsorbents, Adsorption, Aqueous Solution, Aqueous-Solution, Batch, Batch Adsorption, Bentonite, Bodies, Chemisorption, Concentration, Efficacy, Endothermic, Equilibrium, E, periments, Foreign Ions, Heavy-Metals, Humic-Acid, Ionic-Strength, Kinetics, Mechanism, Model, Modified, Montmorillonite, Na-Montmorillonite, Na-Rectorite, Ni²⁺, Nickel, Performance, pH, Pseudo Second Order, Pseudo Second-Order, Pseudo-Second-Order, Redlich-Peterson, Regeneration, Removal, Rights, Second Order, Second-Order, Sodium, Solution, Sorption, Thermodynamics, Uptake

? Liang, S., Guo, X.Y., Feng, N.C. and Tian, Q.H. (2010), Isotherms, kinetics and thermodynamic studies of adsorption of Cu²⁺ from aqueous solutions by Mg²⁺/K⁺ type orange peel adsorbents. Journal of Hazardous Materials, 174 (1-3), 756-762.

Full Text: 2010\J Haz Mat174, 756.pdf

Abstract: Orange peel (OP) was used as raw material to prepare two novel adsorbents: MgOP (Mg²⁺ type orange peel adsorbent) and KOP (K⁺ type orange peel adsorbent). FTIR and SEM were used to characterize the adsorbents. Effects of pH, solid/liquid ratio, time and metal ion concentration on the Cu²⁺ adsorption by these two adsorbents were investigated. The isotherms data were analyzed using the Langrnuir, Freudlich, Temkin and Dubinin-Radushkevich models. Langmuir model provides the best correlation for the adsorption of Cu²⁺ by both MgOP and KOP. and the mono-layer adsorption capacity for Cu²⁺ removal by MgOP and KOP are 40.37 and 59.77 mg/g, respectively. The adsorbed amounts of Cu²⁺ increased with the increase in contact time and reached equilibrium within 20 min. The kinetics data were analyzed using four adsorption kinetic models: the pseudo-first and second-order equations, the Elovich equation and intraparticle diffusion equation. Results show that the pseudo-second-order equation fits the experimental data very well. Thermodynamic studies showed the spontaneous and exothermic nature of the adsorption of Cu²⁺ by MgOP and KOP. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorbents, Adsorption, Adsorption Capacity, Adsorption Kinetic, Aqueous Solutions, Biosorption, Capacity, Concentration, Copper(II), Correlation, Cu²⁺, Data, Diffusion, Dyes, Elovich, Elovich Equation, Equilibrium, Exothermic, Experimental, FTIR, Heavy-Metals, Intraparticle Diffusion, Ions, Isotherms, Kinetic, Kinetic Models, Kinetics, Langmuir, Langmuir Model, Metal, Model, Models, Monolayer, Orange Peel, Orange Peel Adsorbent, Pectin, pH, Pseudo Second Order, Pseudo-First and, Pseudo-Second-Order, Pseudo-Second-Order Equation, Removal, Rights, Second Order, Second-Order, SEM, Solutions, Thermodynamic, Thermodynamic Studies, Valonia Tannin Resin, Waste

? Villa, R.D., Trovó, A.G. and Nogueira, R.F.P. (2010), Soil remediation using a coupled process: soil washing with surfactant followed by photo-Fenton oxidation. Journal of Hazardous Materials,