Personal Research Database

Full Text: 2008\J Haz Mat153, 300.pdf

Abstract: The objectives of the present study were to convert soybean straw to a metal ion adsorbent and further to investigate the potential of using the adsorbent for the removal of Cu²⁺ from aqueous solution. The soybean straw was water or base washed and citric acid (CA) modified to enhance its nature adsorption capacity. The morphological and chemical characteristics of the adsorbent were evaluated by spectroscopy and N₂-adsorption techniques. The porous structure, as well as high amounts of introduced free carboxyl groups of CA modified soybean straw makes the adsorbent be good to retain Cu²⁺. The adsorption capacities increased when the solution pH increased from 2 to 6 and reached the maximum value at pH 6 (0.64 mmol g^-1 for the base washed, CA modified soybean straw (CA-BWSS)). The Cu²⁺ uptake increased and percentage adsorption of the Cu²⁺ decreased with the increase in initial Cu²⁺ concentration from 1 mM to 20 mM. Both the Langmuir and Freundlich adsorption isotherms were tested, and the Freundlich model fited much better than the Langmuir model. It was found that CA-BWSS have the highest adsorption capacity of the four kinds of pretreated soybean straw.

Keywords: Adsorbent, Adsorption, Adsorption Capacities, Adsorption Capacity, Adsorption Isotherm, Adsorption Isotherms, Aqueous Solution, Capacity, Characteristics, Chemical, Citric Acid, Concentration, Copper, Cu²⁺, Freundlich, Freundlich Model, Ions, Isotherms, Langmuir, Langmuir Model, Low Cost Adsorbent, Metal, Model, Modified, N₂ Adsorption, pH, Potential, Removal, Solution, Soybean, Soybean Straw, Spectroscopy, Straw, Structure, Techniques, Uptake, Value, Water

? Demir, H., Top, A., Balköse, D. and Ülkü, S. (2008), Dye adsorption behavior of Luffa cylindrica fibers. Journal of Hazardous Materials, 153 (1-2), 389-394.

Full Text: 2008\J Haz Mat153, 389.pdf

Abstract: Using natural Luffa cylindrica fibers as adsorbent removal of methylene blue dye from aqueous solutions at different temperatures and dye concentrations was investigated in this study. Thermodynamics and kinetics of adsorption were also investigated. The adsorption isotherms could be well defined with Langmuir model instead of Freundlich model. The thermodynamic parameters of methylene blue (MB) adsorption indicated that the adsorption is exothermic and spontaneous. The average MB adsorption capacity was found out as 49 mg, g and average BET surface area of fibers was calculated as 123 m², g. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Behavior, Adsorption Capacity, Adsorption Isotherms, Aqueous Solutions, Behavior, Bet, Bet Surface Area, Capacity, Color Removal, Color Removal, Dye, Dye Adsorption, Exothermic, Fibers, Freundlich, Freundlich Model, Isotherms, Kinetics, Kinetics of Adsorption, Langmuir, Langmuir Model, Luffa Cylindrica, MB, Mechanism, Methylene Blue, Methylene-Blue, Model, Natural, Removal, Rights, Solutions, Surface, Surface Area, Thermodynamic, Thermodynamic Parameters, Thermodynamics

? Vijayaraghavan, K. and Yun, Y.S. (2008), Competition of Reactive red 4, Reactive orange 16 and Basic blue 3 during biosorption of Reactive blue 4 by polysulfone-immobilized Corynebacterium glutamicum. Journal of Hazardous Materials, 153 (1-2), 478-486.

Full Text: 2008\J Haz Mat153, 478.pdf

Abstract: Competition of Reactive red 4 (RR4), Reactive orange 16 (RO16) and Basic blue 3 (BB3) during biosorption of Reactive blue 4 (RB4) by polysulfone-immobilized protonated Corynebacterium glutamicum (PIPC) was investigated in batch and column mode of operations. Through potentiometric titrations, and with the aid of proton-binding model, carboxyl, phosphonate and amine were identified as functional groups of PIPC, with apparent pKa values of 3.47±0.05, 7.08±0.07 and 9.90±0.05 mmol/g, respectively. Since reactive dyes release dye anions (ROSO₃^-) in solutions, the positively charged amine groups were responsible for biosorption. PIPC favored biosorption at pH 3 when RB4 was studied/used as single-solute; while the presence of RR4 and RO16 severely affected the RB4 biosorption. When present as a single-solute, PEPC recorded 184.5 mg RB4/g; while PIPC exhibited 126.9, 120.9 and 169.6 mg RB4/g in the presence of RR4, RO16 and BB3, respectively. In general, the accessibility of amine group depends on the molecular size, number of sulfonate groups and reactivity of each reactive dye. Single and multicomponent Freundlich equations successfully described the biosorption isotherms. With 0.1 M NaOH, it is possible to reuse PIPC for RB4 biosorption in 10 repeated cycles. Column experiments in an up-flow packed column coincided with batch results, that is PIPC showed strong preference towards highly reactive and relatively small RB4 anions; however, the presence of competing dyes hinder the RB4 column biosorption performance. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorption, Aqueous-Solution, Biosorption, Chitosan Beads, Column, Competition, Corynebacterium Glutamicum, Dye, Dyes, Elsevier, Freundlich, Fungal Biomass, Groups, Immobilization, Isotherm, Isotherm, Isotherms, Kinetics, Mechanisms, Model, Multicomponent, Packed Column, pH, Reactive Dye, Reactive Dyes, Reuse, Solutions, Waste Biomass

? Freitas, O.M.M., Martins, R.J.E., Delerue-Matos, C.M. and Boaventura, R.A.R. (2008), Removal of Cd(II), Zn(II) and Pb(II) from aqueous solutions by brown marine macro algae: Kinetic modelling. Journal of Hazardous Materials, 153 (1-2), 493-501.

Full Text: 2008\J Haz Mat153, 493.pdf

Abstract: Specific marine macro algae species abundant at the Portuguese coast (Laminaria hyperborea, Bifurcaria bifurcata, Sargassum muticum and Fucus spiralis) were shown to be effective for removing toxic metals (Cd(II), Zn(II) and Pb(II)) from aqueous solutions. The initial metal concentrations in solution were about 75-100 mg L^-1. The observed biosorption capacities for cadmium, zinc and lead ions were in the ranges of 23.9-39.5, 18.6-32.0 and 32.3-50.4 mg g^-1, respectively. Kinetic studies revealed that the metal uptake rate was rather fast, with 75% of the total amount occurring in the first 10 min for all algal species. Experimental data were well fitted by a pseudo-second order rate equation. The contribution of internal diffusion mechanism was significant only to the initial biosorption stage. Results indicate that all the studied macro algae species can provide an efficient and cost-effective technology for eliminating heavy metals from industrial effluents. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Algae, Aqueous Solutions, Biosorption, Cadmium, Cd(II), Coast, Cost-Effective, Data, Diffusion, Effluents, First, Heavy Metal, Heavy Metals, Internal Diffusion, Kinetic, Kinetic Modelling, Kinetic Studies, Lead, Marine Macro Algae, Mechanism, Metal, Metal Uptake, Metals, Modelling, Pb(II), Pseudo Second Order, Pseudo-Second Order, Pseudo-Second-Order, Removal, Sargassum Muticum, Solution, Solutions, Species, Technology, Toxic Metals, Uptake, Zinc, Zn(II)

? Kadirvelu, K., Goel, J. and Rajagopal, C. (2008), Sorption of lead, mercury and cadmium ions in multi-component system using carbon aerogel as adsorbent. Journal of Hazardous Materials, 153 (1-2), 502-507.

Full Text: 2008\J Haz Mat153, 502.pdf

Abstract: In the present study, adsorption of three metal ions Pb(II), Hg(II) and Cd(II) on carbon aerogel a new form of activated carbon has been investigated in mono- and multi-component (binary and tertiary) system. Batch experiments were also carried out for mono- and multi-component systems with varying metal ion concentration (mg/l) to investigate the competitive adsorption characteristics. Many adsorbents have been studied for their adsorption properties pertaining to mono-component solutions of metal ions. However, to treat wastewater with new materials, their performance needs to be ascertained in multi-component system. The scanning electron micrographs (SEM) and EDAX spectrum of carbon aerogel surfaces before and after the adsorbent was equilibrated with the metal ion solution clearly establishes the presence of the metal ions and some surface modifications can be observed on the carbon aerogel particles adsorption with (i) surface chemistry of the pellets on the surface of carbon aerogel and (II) inside layers of the carbon aerogel. Applicability of the isotherm models namely Freundlich and Langmuir to predict the equilibrium uptake of Pb(II), Hg(II) and Cd(II) in mono-component, binary and tertiary system has also been tested. Langmuir and Freundlich models are found to generally represent the experimental though but not consistently. (c) 2007 Published by Elsevier B.V.

Keywords: Carbon Aerogel, Mono- and Multi-Component, Isotherms, Adsorption Behavior, Competitive Adsorption, Nickel Ions, Biosorption, Removal, Binary, Copper, Waste, Electrodes, Chromium, Biomass

? Cestari, A.R., Vieira, E.E., Tavares, A.M.G. and Bruns, R.E. (2008), The removal of the indigo carmine dye from aqueous solutions using cross-linked chitosan - Evaluation of adsorption thermodynamics using a full factorial design. Journal of Hazardous Materials, 153 (1-2), 566-574.

Full Text: 2008\J Haz Mat153, 566.pdf

Abstract: A 2(3) factorial design was employed to evaluate the quantitative removal of the indigo carmine (IC) dye from aqueous solutions on glutaraldehyde cross-linked chitosan. The variables were chitosan masses of 100 and 300 mg, IC concentrations of 2.0 and 5.0 10^-5 mol L^-1 and temperatures of 25 and 35C. The quantitative and energetic adsorption parameters were analyzed statistically using modeling with bilinear equations. The results indicated that increasing the chitosan mass from 100 to 300 mg decreases the IC adsorption/mass ratio (mol g^-1) whereas a temperature increase of 25-35C increases it. The principal effect of the IC concentration did not show statistical significance. The factorial experiments demonstrate the existence of a significant antagonistic interaction effect between the chitosan mass and temperature.

The adsorption thermodynamic parameters, namely H, G, and S, were determined for all the factorial design results. Endothermic values were found in relation to the H. The positive S values indicate that entropy is a driving force for adsorption. The G values are also significantly affected by important antagonistic and synergistic effects involving all principal and interactive factors. It is concluded that the thermodynamical spontaneity of the IC adsorption parameters are greatly influenced by the interactive factors and not by the temperature changes alone. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Chitosan, Removal of Dyes, Adsorption Thermodynamics, Chemometrics, Waste-Water, Anionic Dyes, Activated Bentonite, Thermochemical Data, Silica-Gel, Kinetics, Parameters, Membranes, Chitin, Beads

? Demirbaş, Ö., Karadaǧ, A., Alkan, M. and Doǧan, M. (2008), Removal of copper ions from aqueous solutions by hazelnut shell. Journal of Hazardous Materials, 153 (1-2), 677-684.

Full Text: 2008\J Haz Mat153, 677.pdf

Abstract: There is a great potential of woody hazelnut shell to use in some applications. Sorption studies are one of these. For this reason in this paper, batch adsorption of Cu²⁺ ions onto hazelnut shells was studied. The capacity of the adsorption for the removal of copper ions from aqueous solution was investigated under different conditions such as solution contact time (1-360 min), particle size (0-75, 75-150 and 150-200 m), temperature of solution (25-60 degrees) and solution pH (3-7). Moreover, zeta potential of particles at different initial pHs (2-10) was measured. The equilibrium data were processed according to Langmuir and Freundlich’s models and higher adsorption capacity values towards Cu²⁺ ions were shown. The adsorption kinetics was investigated and the best fit was achieved by a second-order equation. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Acid, Activated Carbon, Adsorption, Adsorption, Adsorption Capacity, Adsorption Kinetics, Aqueous Solution, Aqueous Solutions, Batch, Batch Adsorption, Capacity, Contact, Copper, Copper Ion, Copper Ions, Cu²⁺, Data, Equilibrium, Hazelnut Shell, Heavy-Metals, Industrial Effluents, Ions, Kinetics, Langmuir, Methyl Violet, Models, Nickel Removal, Particle Size, Particles, pH, Potential, Removal, Rights, Second Order, Second-Order, Second-Order Equation, Sepiolite, Size, Solution, Solutions, Sorption, Temperature, Time, Values, Zeta Potential

? Hameed, B.H. and El-Khaiary, M.I. (2008), Kinetics and equilibrium studies of malachite green adsorption on rice straw-derived char. Journal of Hazardous Materials, 153 (1-2), 701-708.

Full Text: 2008\J Haz Mat153, 701.pdf

Abstract: In this work, the potential feasibility of rice straw-derived char (RSC) for removal of C.I. Basic Green 4 (malachite green (MG)), a cationic dye from aqueous solution was investigated. The isotherm parameters were estimated by non-linear regression analysis. The equilibrium process was described well by the Langmuir isotherm model. The maximum RSC sorption capacity was found to be 148.74 mg/L at 30C. The kinetics of MG sorption on RSC followed the Lagergren’s pseudo-first-order model and the overall rate of dye uptake was found to be controlled by external mass transfer at the beginning of adsorption, while intraparticle diffusion controlled the overall rate of adsorption at a later stage. The results indicated that RSC was an attractive adsorbent for removing basic dye from aqueous solutions. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Isotherm, Analysis, Aqueous Solution, Aqueous Solutions, Basic Dye, Capacity, Cationic Dye, Char, Diffusion, Dye, Equilibrium, Equilibrium Studies, Feasibility, Intraparticle Diffusion, Isotherm, Isotherm Model, Isotherm Parameters, Kinetics, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Malachite Green, Mass Transfer, Mg, Model, Non-Linear Regression, Nonlinear Regression, Potential, Pseudo First Order, Pseudo-First-Order, Regression, Regression Analysis, Removal, Rice, Rice Straw, Solution, Solutions, Sorption, Sorption Capacity, Uptake, Work

? Tan, I.A.W., Ahmad, A.L. and Hameed, B.H. (2008), Preparation of activated carbon from coconut husk: Optimization study on removal of 2,4,6-trichlorophenol using response surface methodology. Journal of Hazardous Materials, 153 (1-2), 709-717.

Full Text: 2008\J Haz Mat153, 709.pdf

Abstract: Activated carbon was prepared from coconut husk using physicochemical activation method which consisted of potassium hydroxide (KOH) treatment and carbon dioxide (CO2) gasification. The effects of three preparation variables (CO2 activation temperature, CO2 activation time and KOH:char impregnation ratio) on the 2,4,6-trichlorophenol (2,4,6-TCP) uptake and activated carbon yield were investigated. Based on the central composite design, two quadratic models were developed to correlate the preparation variables to the two responses. From the analysis of variance (ANOVA), the most influential factor on each experimental design response was identified. The activated carbon preparation conditions were optimized by maximizing both the 2,4,6-TCP uptake and activated carbon yield. The predicted 2,4,6-TCP uptake and carbon yield from the models agreed satisfactorily with the experimental values. The optimum conditions for preparing activated carbon from coconut husk for adsorption of 2,4,6-TCP were found as follow: CO2 activation temperature of 750 degrees C, CO2 activation time of 2.29 h and KOH:char impregnation ratio of 2.91, which resulted in 191.73 mg/g of 2,4,6-TCP uptake and 20.16% of activated carbon yield. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: 2,4,6-Trichlorophenol, Activated Carbon, Activation, Activation Temperature, Adsorption, Adsorption Characteristics, Analysis, Aqueous-Solutions, Carbon, Carbon Dioxide, Central Composite Design, Chemical Activation, Chlorophenols, Co2, Co2 Activation, Coconut Husk, Coconut Husk Activated Carbon, Composite, Experimental Design, Impregnation, Kinetics, Methylene-Blue, Models, Optimization, Palm Shell, Potassium Hydroxide, Preparation, Removal, Sewage-Sludge, Temperature, Treatment, Uptake, Water

? Gupta, V.K. and Rastogi, A. (2008), Equilibrium and kinetic modelling of cadmium(II) biosorption by nonliving algal biomass Oedogonium sp from aqueous phase. Journal of Hazardous Materials, 153 (1-2), 759-766.

Full Text: 2008\J Haz Mat153, 759.pdf

Abstract: The biosorption of cadmium(II) ions on Oedogonium sp. is studied in a batch system with respect to initial pH, algal dose, contact time and the temperature. The algal biomass exhibited the highest cadmium(II) uptake capacity at 25C, at the initial pH value of 5.0 in 55 min and at the initial cadmium(II) ion concentration of 200 mg L^-1. Biosorption capacity decreased from 88.9 to 80.4 mg g^-1 with an increase in temperature from 25 to 45C at this initial cadmium(II) concentration. Uptake kinetics follows the pseudo-second-order model and equilibrium is well described by Langmuir isotherm. Isotherms have been used to determine thermodynamic parameters of the process, viz., free energy change, enthalpy change and entropy change. FTIR analysis of algal biomass revealed the presence of amino, carboxyl, hydroxyl and carbonyl groups, which are responsible for biosorption of metal ions. Acid pretreatments did not substantially increase metal sorption capacity but alkali like NaOH pretreatment slightly enhanced the metal removal ability of the biomass. During repeated sorption/desorption cycles at the end of fifth cycle, Cd(II) sorption decreased by 18%, with 15-20% loss of biomass. Nevertheless, Oedogonium sp. appears to be a good sorbent for removing metal Cd(II) from aqueous phase. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Analysis, Aqueous Phase, Batch, Batch System, Biomass, Biosorption, Cadmium, Cadmium(II), Cadmium(II) Ions, Capacity, Cd(II), Concentration, Energy, Enthalpy, Entropy, Equilibrium, FTIR, Isotherm, Isotherms, Kinetic, Kinetic Modelling, Kinetics, Langmuir, Langmuir Isotherm, Langmuir Model, Metal, Metal Ions, Metal Sorption, Model, Modelling, NaOH, Oedogonium sp., pH, pH Value, Pretreatment, Pretreatments, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Removal, Sorbent, Sorption, Sorption Capacity, Sorption, Desorption, Temperature, Thermodynamic, Thermodynamic Parameters, Uptake, Value

? Alkan, M., Kalay, B., Doğan, M. and Demirbaş, Ö. (2008), Removal of copper ions from aqueous solutions by kaolinite and batch design. Journal of Hazardous Materials, 153 (1-2), 867-876.

Full Text: 2008\J Haz Mat153, 867.pdf

Abstract: The removal of copper ions from aqueous solutions by kaolinite was investigated by using a batch-type method. Effects of factors such as pH, ionic strength, temperature, acid-activation and calcination on copper adsorption were investigated. The uptake of copper was determined from changes in concentration as measured by atomic absorption spectrometry. The extent of copper adsorption increased with increasing pH and temperature and with decreasing ionic strength, acid-activation and calcination temperature. The Langmuir and Freundlich adsorption models were used to determine the isotherm parameters associated with the adsorption process. The results provide support for the adsorption of copper ions onto kaolinite. Thermodynamic parameters indicated the endothermic nature of copper adsorption on kaolinite. The experimental results were applied a batch design. As a result, the kaolinite may be used for removal of copper ions from aqueous solutions. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Absorption, Acid Activation, Acid-Activation, Activated Carbon, Adsorption, Adsorption, Adsorption Process, Aqueous Solutions, Atomic Absorption Spectrometry, Batch, Cadmium, Calcination, Changes, Chromium(VI), Concentration, Copper, Copper Adsorption, Copper Ion, Design, Endothermic, Equilibrium, Experimental, Freundlich, Fullers Earth, Intercalation, Ionic Strength, Ions, Isotherm, Isotherm Parameters, Kaolinite, Langmuir, Methylene-Blue, Models, Natural Kaolinite, pH, Removal, Rights, Sepiolite, Solutions, Spectrometry, Strength, Support, Temperature, Thermodynamic, Thermodynamic Parameters, Uptake

? Bouraada, M., Lafjah, M., Ouali, M.S. and de Menorval, L.C. (2008), Basic dye removal from aqueous solutions by dodecylsulfate- and dodecyl benzene sulfonate-intercalated hydrotalcite. Journal of Hazardous Materials, 153 (3), 911-918.

Full Text: 2008\J Haz Mat153, 911.pdf

Abstract: Dodecylsulfate- and dodecyl benzene sulfonate-hydrotalcites were prepared by calcination-rehydratation method. The surfactants intercalation in the interlayer space of hydrotalcite were checked by PXRD and FTIR spectroscopy where the resulting materials were found to be similar to those reported in the literature and were used to remove a basic dye (safranine) from aqueous solutions. The sorption kinetics data fitted the pseudo second order model. The isotherms were established and the parameters calculated. The sorption data fitted the Langmuir model with good values of the determination coefficient. The thermodynamic parameters calculated from Van’t Hoff plots gave a low value of G (<-20 kJ mol^-1) indicating a spontaneous physisorption process. Two regeneration cycles were processed by acetone extraction leading to the same removal capacity of the obtained materials as the original surfactant-intercalated hydrotalcites. The UV-vis spectra of the recovered extracts were similar to the spectrum of safranine, which means that the dye was recovered without any modification. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Acetone, Aqueous Solutions, Basic Dye, Benzene, Capacity, Data, Dye, Dye Removal, Extraction, FTIR, Hydrotalcite, Hydrotalcites, Isotherms, Kinetics, Langmuir, Langmuir Model, Literature, Model, Modification, Pseudo Second Order, Pseudo-Second-Order, Regeneration, Removal, Second Order, Second-Order, Solutions, Sorption, Sorption Isotherm, Sorption Kinetics, Spectroscopy, Surfactant-Intercalated Hydrotalcite, Surfactants, Thermodynamic, Thermodynamic Parameters, Value

? El-Sofany, E.A. (2008), Removal of lanthanum and gadolinium from nitrate medium using Aliquat-336 impregnated onto Amberlite XAD-4. Journal of Hazardous Materials, 153 (3), 948-954.

Full Text: 2008\J Haz Mat153, 948.pdf

Abstract: Aliquat-336 in benzene was supported on Amberlite XAD-4 crosslinked polystyrene resin. The use of XAD-4 impregnated with Aliquat-336 resin for removal of lanthanum(III) and gadolinium(III) from nitrate medium was carried out using batch technique. Various parameters affecting the uptake of these metal ions such as contact time, metal ion concentrations, V/m and pH value were separately studied. Effect of temperature on the equilibrium distribution values has been studied to evaluate the changes in standard thermodynamic quantities. A comparison of kinetic models applied to the adsorption rate data was evaluated for Lagergren first order, the pseudo second order and Morris-Weber kinetic models. From the results, both pseudo second order and intraparticle diffusion models were found to best correlate the experimental rate data. The capacity of the impregnated resin for both lanthanum(III) and gadolinium(III) was found to be 4.73 and 4.44 mg/g. From the results, impregnation of Aliquat-336 onto Amberlite XAD-4 provides an efficient impregnated resin for the removal of lanthanum(III) and gadolinium(IIII) from 0.1 M nitrate aqueous solution. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Rate, Aliquat-336, Amberlite XAD-4, Aqueous Solution, Batch, Benzene, Capacity, Changes, Comparison, Data, Diffusion, Distribution, Equilibrium, Experimental, First, First Order, Impregnation, Intraparticle Diffusion, Kinetic, Kinetic Models, Lanthanides, Metal, Metal Ions, Models, Nitrate, Nitrate Medium, pH, pH Value, Polystyrene, Pseudo Second Order, Pseudo-Second-Order, Removal, Resin, Second Order, Second-Order, Solution, Standard, Temperature, Thermodynamic, Uptake, Value, XAD-4

? Santos, S.C.R., Vilar, V.J.P. and Boaventura, R.A.R. (2008), Waste metal hydroxide sludge as adsorbent for a reactive dye. Journal of Hazardous Materials,