Personal Research Database

Full Text: 2008\J Haz Mat154, 221.pdf

Abstract: Multi-component sorption studies were carried out for attenuation of divalent heavy metal cations (Pb²⁺, Cu²⁺, and Znv) by a low-cost mineral adsorbent from the aqueous solution. Kinetic and equilibrium batch-type sorption experiments were conducted under variable conditions for multicomponent using low-grade (<12% P₂O₅) phosphate rock. Percentage of multiple heavy metal species removal increases with decreasing initial metals concentration and particle size. The equilibrium data were well described to a lesser extent by Freundlich model but Langmuir model seemed to be more appropriate with the fixation capacity obtained at room temperature for Pb²⁺, Cu²⁺ and Zn²⁺ was 227.2, 769.2 and 666.6 mu mol g^-1, respectively. Two simple kinetic models were tested to investigate the adsorption mechanism. Rate constants have been found nearly constant at all metal concentrations for first order. The comparison of adsorption capacity of low-grade phosphate rock decreases in multi-component system as compared to single component due to ionic interactions. X-ray powder diffraction (XRPD) technique was used to ascertain the formation of new metal phases followed by surface complexation. Used adsorbents have been converted into a value added product by utilizing innovative Zero-waste concept to solve the used adsorbents disposal problem and thus protecting the environment. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Multi-Component Sorption, Divalent Heavy Metal Ions, Ionic Interaction, X-Ray Powder Diffraction, Zero-Waste Concept, Divalent Metal-Ions, Single-Component, Heavy-Metals, Adsorption, Hydroxyapatite, Water, Immobilization, Zeolites, Kinetics, Removal

? Hameed, B.H. and El-Khaiary, M.I. (2008), Batch removal of malachite green from aqueous solutions by adsorption on oil palm trunk fibre: Equilibrium isotherms and kinetic studies. Journal of Hazardous Materials, 154 (1-3), 237-244.

Full Text: 2008\J Haz Mat154, 237.pdf

Abstract: Oil palm trunk fibre (OPTF) - an agricultural solid waste - was used as low-cost adsorbent to remove malachite green (MG) from aqueous solutions. The operating variables studied were contact time, initial dye concentration, and solution pH. Equilibrium adsorption data were analyzed by three isotherms, namely the Freundlich isotherm, the Langmuir isotherm, and the multilayer adsorption isotherm. The best fit to the data was obtained with the multilayer adsorption. The monolayer adsorption capacity of OPTF was found to be 149.35 mg/g at 30C. Adsorption kinetic data were modeled using the Lagergren pseudo-first-order, Ho’s pseudo-second-order and Elovich models. It was found that the Lagergren’s model could be used for the prediction of the system’s kinetics. The overall rate of dye uptake was found to be controlled by external mass transfer at the beginning of adsorption, then for initial MG concentrations of 25, 50, 100, 150, and 300 mg/L the rate-control changed to intraparticle diffusion at a later stage, but for initial MG concentrations 200 and 250 mg/L no evidence was found of intraparticle diffusion at any period of adsorption. It was found that with increasing the initial concentration of MG, the pore-diffusion coefficient increased while the film-diffusion coefficient decreased. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Adsorption, Adsorption Capacity, Adsorption Isotherm, Adsorption Kinetic, Agricultural, Agricultural Solid Waste, Agricultural Waste, Aqueous Solutions, Ash, Basic Dye, Capacity, Concentration, Contact, Data, Diffusion, Dye, Elovich, Equilibrium, Equilibrium Isotherms, Evidence, Film Diffusion, Freundlich, Freundlich Isotherm, Industry Waste, Intraparticle, Intraparticle Diffusion, Isotherm, Isotherms, Kinetic, Kinetic Studies, Kinetics, Lagergren, Langmuir, Langmuir Isotherm, Low Cost, Low Cost Adsorbent, Low-Cost Adsorbent, Malachite Green, Mass, Mass Transfer, Methylene-Blue, Mg, Model, Models, Monolayer, Multilayer, Oil Palm Trunk, pH, Photo-Fenton Degradation, Pore Diffusion, Prediction, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Removal, Rights, Sawdust, Solid Waste, Solution, Solutions, Uptake, Waste, Waste-Water

? Bekçi, Z., Özveri, C., Seki, Y. and Yurdakoç, K. (2008), Sorption of malachite green on chitosan bead. Journal of Hazardous Materials, 154 (1-3), 254-261.

Full Text: 2008\J Haz Mat154, 254.pdf

Abstract: Chitosan bead was synthesized for the removal of a cationic dye malachite green (MG) from aqueous solution. The effects of temperature (303, 313 and 323 K), pH of the solution (2-11) on MG removal was investigated. Preliminary kinetic experiment was carried out up to 480 min. The sorption equilibrium was reached within 5 h (300 min). In order to determine the adsorption capacity, the sorption data were analyzed using linear form of Langmuir and Freundlich equation. Langmuir equation showed higher conformity than Freundlich equation. Ninety-nine percent removal of MG was reached at the optimum pH value of 8. From kinetic experiments, it was obtained that sorption process followed the pseudo-second-order kinetic model. This study showed that chitosan beads can be excellent adsorbents at high pH values. Activation energy value for sorption process was found to be 85.6 kJ mol^-1. This indicates that sorption process can be assumed as chemical process. Due to negative values of Gibbs free energy, sorption process can be considered as a spontaneous. In order to determine the interactions between MG and chitosan bead, FTIR analysis was also conducted. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Activation, Activation Energy, Adsorbents, Adsorption, Adsorption Capacity, Analysis, Aqueous Solution, Beads, Capacity, Cationic Dye, Chemical, Chitosan, Chitosan Bead, Data, Dye, Energy, Equilibrium, Experiment, Experiments, Freundlich, Freundlich Equation, FTIR, Gibbs Free Energy, Kinetic, Kinetic Model, Langmuir, Langmuir Equation, Malachite Green, Mg, Model, pH, pH Value, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Removal, Solution, Sorption, Sorption Process, Temperature, Value

? Tan, I.A.W., Ahmad, A.L. and Hameed, B.H. (2008), Adsorption of basic dye on high-surface-area activated carbon prepared from coconut husk: Equilibrium, kinetic and thermodynamic studies. Journal of Hazardous Materials, 154 (1-3), 337-346.

Full Text: 2008\J Haz Mat154, 337.pdf

Abstract: Adsorption isotherm and kinetics of methylene blue on activated carbon prepared from coconut husk were determined from batch tests. The effects of contact time (1–30 h), initial dye concentration (50–500 mg/l) and solution temperature (30–50 °C) were investigated. Equilibrium data were fitted to Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. The equilibrium data were best represented by Langmuir isotherm model, showing maximum monolayer adsorption capacity of 434.78 mg/g. The kinetic data were fitted to pseudo-first-order, pseudo-second-order and intraparticle diffusion models, and was found to follow closely the pseudo-second-order kinetic model. Thermodynamic parameters such as standard enthalpy (ΔH°), standard entropy (ΔS°) and standard free energy (ΔG°) were evaluated. The adsorption interaction was found to be exothermic in nature. Coconut husk-based activated carbon was shown to be a promising adsorbent for removal of methylene blue from aqueous solutions.

Keywords: Activated Carbon, Adsorbent, Adsorption, Adsorption Capacity, Adsorption Isotherm, Aqueous Solutions, Basic Dye, Batch, Capacity, Carbon, Coconut Husk, Coconut Husk Activated Carbon, Concentration, Data, Diffusion, Dye, Energy, Enthalpy, Entropy, Equilibrium, Exothermic, Freundlich, Interaction, Intraparticle Diffusion, Isotherm, Isotherm Model, Kinetic, Kinetic Model, Kinetics, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Methylene Blue, Model, Models, Monolayer, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Removal, Solution, Solutions, Standard, Temperature, Thermodynamic, Thermodynamic Parameters, Thermodynamic Studies

? Gupta, V.K. and Rastogi, A. (2008), Sorption and desorption studies of chromium(VI) from nonviable cyanobacterium Nostoc muscorum biomass. Journal of Hazardous Materials, 154 (1-3), 347-354.

Full Text: 2008\J Haz Mat154, 347.pdf

Abstract: This communication presents results pertaining to the sorptive and desorptive studies carried out on chromium(VI) removal onto nonviable freshwater cyanobacterium (Nostoc muscorum) biomass. Influence of varying the conditions for removal of chromium(VI), such as the pH of aqueous solution, the dosage of biosorbent, the contact time with the biosorbent, the temperature for the removal of chromium, the effect of light metal ions and the adsorption-desorption studies were investigated. Sorption interaction of chromium on to cyanobacterial species obeyed both the first and the second-order rate equation and the experimental data showed good fit with both the Langmuir and freundlich adsorption isotherm models. The maximum adsorption capacity was 22.92 mg/g at 25C and pH 3.0. The adsorption process was endothermic and the values of thermodynamic parameters of the process were calculated. Various properties of the cyanobacterium, as adsorbent, explored in the characterization part were chemical composition of the adsorbent, surface area calculation by BET method and surface functionality by FTIR. Sorption-desorption of chromium into inorganic solutions and distilled water were observed and this indicated the biosorbent could be regenerated using 0.1 M HNO₃ and EDTA with upto 80% recovery. The biosorbents were reused in five biosorption-desorption cycles without a significant loss in biosorption capacity. Thus, this study demonstrated that the cyanobacterial biomass N. muscorum could be used as an efficient biosorbent for the treatment of chromium(VI) bearing wastewater. © 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Capacity, Adsorption Isotherm, Aqueous Solution, BET, Biomass, Biosorbent, Biosorption, Biosorption-Desorption, Capacity, Characterization, Chromium, Chromium(VI), Communication, Cr(VI), Desorption, EDTA, Endothermic, Equilibrium, Experimental, First, Freshwater, FTIR, Green-Algae, Heavy-Metal Biosorption, Hexavalent Chromium, Interaction, Ions, Isotherm, Kinetics, Langmuir, Langmuir Model, Metal, Metal Ions, Models, Nickel(II), Nostoc Muscorum, pH, Recovery, Removal, Rhizopus-Arrhizus, Rights, Solution, Sorption, Sorption-Desorption, Surface Area, Temperature, Thermodynamic, Thermodynamic Parameters, Treatment, Wastewater, Water

? Xu, D., Tan, X.L., Chen, C.L. and Wang, X.K. (2008), Removal of Pb(II) from aqueous solution by oxidized multiwalled carbon nanotubes. Journal of Hazardous Materials, 154 (1-3), 407-416.

Full Text: 2008\J Haz Mat154, 407.pdf

Abstract: Oxidized multiwalled carbon nanotubes (MWCNTs) were employed as sorbent to study the sorption characteristic of Pb(II) from aqueous solution as a function of contact time, pH, ionic strength, foreign ions, and oxidized MWCNTs’ contents under ambient conditions using batch technique. The results indicate that sorption of Pb(II) on oxidized MWCNTs is strongly dependent on pH values, and independent of ionic strength and the type of foreign ions. The removal of Pb(II) to oxidized MWCNTs is rather quickly and the kinetic sorption can be described by a pseudo-second-order model very well. Sorption of Pb(II) is mainly dominated by surface complexation rather than ion exchange. The efficient removal of Pb(II) from aqueous solution is limited at pH 7-10. X-ray photoelectron spectroscopy (XPS) is performed to study the sorption mechanism at a molecular level and thereby to identify the species of the sorption processes. The 3-D relationship of pH, C-eq and q indicates that all the data of C-eq - q lie in a straight line with slope - V/m and intercept C0V/m for the same initial concentration of Pb(II) and same content of oxidized MWCNTs of each experimental data. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: 3D, Aqueous Solution, Batch, Carbon, Carbon Nanotubes, Complexation, Concentration, Data, Experimental, Foreign Ions, Function, Ion Exchange, Ion-Exchange, Ionic Strength, Kinetic, Kinetic Sorption, Mechanism, Model, Multiwalled Carbon Nanotubes, Mwcnts, Nanotubes, Pb(II), pH, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Removal, Solution, Sorbent, Sorption, Sorption Mechanism, Species, Spectroscopy, Strength, Surface, Surface Complexation, X-Ray, XPS

? Ertugay, N. and Bayhan, Y.K. (2008), Biosorption of Cr(VI) from aqueous solutions by biomass of Agaricus bisporus. Journal of Hazardous Materials, 154 (1-3), 432-439.

Full Text: 2008\J Haz Mat154, 432.pdf

Abstract: In this study, biosorption of Cr(VI) ion was investigated by using biomass of Agaricus bisporus (a species of mushroom) in a temperature and shaking speed controlled shaker. The effect of shaking speed, biomass concentration, initial metal ion concentration and initial pH on biosorption yield was determined and the fitness of biosorption data for Freundlich and Langmuir adsorption models was investigated. Optimum biosorption conditions were found to be pH 1, C-0 = 50 mg/l, m = 10 g/l, shaking speed = 150 rpm, T = 20C Cr(VI), respectively. It was found that biosorption of Cr(VI) ions onto biomass of A. bisporus was better suitable to Freundlich adsorption model than Langmuir adsorption model. The correlation coefficients for the second-order kinetic model obtained were found to be 0.999 for all concentrations. These indicate that the biosorption system studied belongs to the second-order kinetic model. (C) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Agaricus Bisporus, Aqueous Solutions, Batch, Biomass, Biosorption, Biosorption Isotherms, Chromium, Chromium(VI), Cr(VI), Equilibrium, Fitness, Freundlich, Heavy-Metals, Ions, Kinetic, Kinetic Model, Kinetic Modeling, Langmuir, Metal, Model, Models, Nickel(II), pH, Removal, Rights, Tea Factory Waste, Temperature

? Sun, W.L., Qu, Y.Z., Yu, Q. and Ni, J.R. (2008), Adsorption of organic pollutants from coking and papermaking wastewaters by bottom ash. Journal of Hazardous Materials, 154 (1-3), 595-601.

Full Text: 2008\J Haz Mat154, 595.pdf

Abstract: Bottom ash, a power plant waste, was used to remove the organic pollutants in coking wastewater and papermaking wastewater. Particular attention was paid on the effect of bottom ash particle size and dosage on the removal of chemical oxygen demand (COD). UV-vis spectra, fluorescence excitation-emission matrix (FEEM) spectra, Fourier transform infrared (FTIR) spectra, and scanning electron microscopic (SEM) photographs were investigated to characterize the wastewaters and bottom ash. The results show that the COD removal efficiencies increase with decreasing particle sizes of bottom ash, and the COD removal efficiency for coking wastewater is much higher than that for papermaking wastewater due to its high percentage of particle organic carbon (POC). Different trends of COD removal efficiency with bottom ash dosage are also observed for coking and papermaking wastewaters because of their various POC concentrations. Significant variations are observed in the FEEM spectra of wastewaters after treatment by bottom ash. New excitation-emission peaks are found in FEEM spectra, and the fluorescence intensities of the peaks decrease. A new transmittance band in the region of 1400-1420 m^-1 is observed in FTIR spectra of bottom ash after adsorption. The SEM photographs reveal that the surface of bottom ash particles varies evidently after adsorption.

Keywords: Adsorption, Bottom Ash, Carbon, Chemical, Chemical Oxygen Demand, COD, Coking Wastewater, Demand, Efficiency, Fluorescence, FTIR, FTIR Spectra, Matrix, Organic, Organic Carbon, Organic Pollutants, Oxygen, Papermaking, Papermaking Wastewater, Particle Size, Particles, Plant, Pollutants, Power, Power Plant, Removal, Removal Efficiency, SEM, Size, Surface, Treatment, Trends, Waste, Wastewater, Wastewaters

? Shayestehfar, M.R., Nasab, S.K. and Mohammadalizadeh, H. (2008), Mineralogy, petrology, and chemistry studies to evaluate oxide copper ores for heap leaching in Sarcheshmeh copper mine, Kerman, Iran. Journal of Hazardous Materials, 154 (1-3), 602-612.

Full Text: 2008\J Haz Mat154, 602.pdf

Abstract: In recent years, as a result of biological, environmental, and economic considerations, available copper in copper oxide ores that could not be recovered by pyrometallurgical methods was accumulated in so-called oxide dumps. Suitable material is treated with dilute sulfuric acid in a heap-leaching process, whereupon the copper content of the rock slowly dissolves in the acidic solution. The performed investigations show that one needs to consider the action of the acid on the copper oxide-containing rocks at the microscopic level. In this paper, we describe research carried out on oxide samples from the western dump of the Sarcheshmeh copper mine. Each sample was split into two parts and a portion of each was exposed to heap-leaching conditions in a column. Subsequently, polished sections, thin sections, and powdered samples were subjected to chemical analysis as well as petrographic and mineralogical considerations. Changes in the weight percentages of non-metal and metal minerals before and after acid treatment were measured. Microscopic studies have indicated that chemical analyses do not provide a complete picture of the effects of acid on the rock. Thus, microscopic studies on sections are shown to be a necessary requirement, neglection of which can have negative economic and environmental effects.

Keywords: Acid Treatment, Acid-Treatment, Analyses, Analysis, Biological, Chemical, Chemical Analysis, Chemistry, Column, Copper, Economic, Environmental, Heap Leaching, Investigations, Iran, Leaching, Metal, Methods, Mineralogy, Minerals, Needs, Oxide, Oxide Copper Ore, Petrography, Requirement, Research, Solution, Treatment

? Bulut, E., Özacar, M. and Şengil, İ.A. (2008), Equilibrium and kinetic data and process design for adsorption of Congo Red onto bentonite. Journal of Hazardous Materials, 154 (1-3), 613-622.

Full Text: 2008\J Haz Mat154, 613.pdf

Abstract: The adsorption of Congo Red onto bentonite in a batch adsorber has been studied. Four kinetic models, the pseudo first- and second-order equations, the Elovich equation and the intraparticle diffusion equation, were selected to follow the adsorption process. Kinetic parameters; rate constants, equilibrium adsorption capacities and correlation coefficients, for each kinetic equation were calculated and discussed. It was shown that the adsorption of Congo Red onto bentonite could be described by the pseudo second-order equation. The experimental isotherm data were analyzed using the Langmuir, Freundlich and Temkin equations. Adsorption of Congo Red onto bentonite followed the Langmuir isotherm. A single stage batch adsorber was designed for different adsorbent mass/treated effluent volume ratios using the Langmuir isotherm. © 2007 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Adsorption, Adsorption Capacities, Adsorption Kinetics and Isotherm, Aqueous-Solution, Aspergillus-Niger, Batch, Batch Adsorber Design, Batch Adsorber Design, Bentonite, Calcined Alunite, Congo Red, Contact Time, Correlation, Data, Design, Diffusion, Disperse Dyes, Elovich, Elovich Equation, Equilibrium, Experimental, First, Fly-Ash, Freundlich, Intraparticle Diffusion, Isotherm, Kinetic, Kinetic Equation, Kinetic Models, Kinetic Parameters, Langmuir, Langmuir Isotherm, Methylene-Blue, Models, Process Design, Pseudo Second Order, Pseudo Second-Order, Pseudo Second-Order Equation, Pseudo-Second-Order, Rate Constants, Rights, Second Order, Second-Order, Second-Order Equation, Thermo-Xrd-Analysis, Volume

? Hameed, B.H. and El-Khaiary, M.I. (2008), Sorption kinetics and isotherm studies of a cationic dye using agricultural waste: Broad bean peels. Journal of Hazardous Materials, 154 (1-3), 639-648.

Full Text: 2008\J Haz Mat154, 639.pdf

Abstract: In this paper, broad bean peels (BBP), an agricultural waste, was evaluated for its ability to remove cationic dye (methylene blue) from aqueous solutions. Batch mode experiments were conducted at 30C. Equilibrium sorption isotherms and kinetics were investigated. The kinetic data obtained at different concentrations have been analyzed using pseudo-first-order, pseudo-second-order and intraparticle diffusion equations. The experimental data fitted very well the pseudo-first-order kinetic model. Analysis of the temportal change of q indicates that at the beginning of the process the overall rate of adsorption is controlled by film-diffusion, then at later stage intraparticle-diffusion controls the rate. Diffusion coefficients and times of transition from film to pore-diffusion control were estimated by piecewise linear regression. The experimental data were analyzed by the Langmuir and Freundlich models. The sorption isotherm data fitted well to Langmuir isotherm and the monolayer adsorption capacity was found to be 192.7 mg/g and the equilibrium adsorption constant K-a is 0.07145 l/mg at 30C. The results revealed that BBP was a promising sorbent for the removal of methylene blue from aqueous solutions. (c) 2007 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Capacity, Adsorption Isotherm, Agricultural, Agricultural Waste, Aqueous Solutions, Broad Bean Peel, Capacity, Cationic Dye, Control, Data, Diffusion, Dye, Equilibrium, Experimental, Experiments, Freundlich, Intraparticle Diffusion, Isotherm, Isotherms, Kinetic, Kinetic Model, Kinetics, Langmuir, Langmuir Isotherm, Linear Regression, Methylene Blue, Mode, Model, Models, Monolayer, Pore Diffusion, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Regression, Removal, Solutions, Sorbent, Sorption, Sorption Isotherm, Sorption Isotherms, Sorption Kinetics, Waste

? El-Naggar, M.R., El-Kamash, A.M., El-Dessouky, M.I. and Ghonaim, A.K. (2008), Two-step method for preparation of NaA-X zeolite blend from fly ash for removal of cesium ions. Journal of Hazardous Materials, 154 (1-3), 963-972.

Full Text: 2008\J Haz Mat154, 963.pdf

Abstract: Pure zeolites can be synthesized from silica extracts obtained from fly ash by alkaline leaching. The extraction potential of industrial by-product fly ash was investigated under repeated fusion process conditions. The amount of extracted silica was 131.43 g/kg ash while the amount extracted alumina was limited to 41.72 g/kg ash. The results of zeolite synthesis from the Si-bearing extracts demonstrated that pure zeolites with high cation exchange capacity (4.624 meq/g) can be produced. The sorption potential of synthesized A-X zeolite blend for the removal of cesium ions has been investigated. The influences of pH, contact time and temperature have been reported. Thermodynamic parameters such as changes in Gibbs free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) were calculated. A comparison of kinetic models applied to the sorption data was evaluated for pseudo first-order, pseudo second-order and homogeneous particle diffusion models. The results showed that both the pseudo second-order and the homogeneous particle diffusion models were found to best correlate the experimental rate data. © 2007 Elsevier B.V. All rights reserved.

Keywords: Alumina, Capacity, Cation, Cation Exchange, Cesium, Changes, Comparison, Data, Diffusion, Energy, Enthalpy, Entropy, Experimental, Extraction, First Order, Fly Ash, Fusion, Gibbs Free Energy, Kinetic, Kinetic Modeling, Kinetic Models, Leaching, Models, Particle Diffusion, pH, Potential, Preparation, Pseudo First Order, Pseudo First-Order, Pseudo Second Order, Pseudo Second-Order, Pseudo-First-Order, Pseudo-Second-Order, Removal, Second Order, Second-Order, Silica, Sorption, Sorption Potential, Synthesis, Temperature, Thermodynamic, Thermodynamic Parameters, Zeolite, Zeolite A-X, Zeolites

? Şeker, A., Shahwan, T., Eroğlu, A.E., Yılmaz, S., Demirel, Z. and Dalay, M.C. (2008), Equilibrium, thermodynamic and kinetic studies for the biosorption of aqueous lead(II), cadmium(II) and nickel(II) ions on Spirulina platensis. Journal of Hazardous Materials,