Personal Research Database

Full Text: 2006\J Haz Mat136, 345.pdf

Abstract: The untreated, heat- and alkali-treated Lentinus sajor-caju mycelia were used for the recovery of uranium from aqueous solutions. The effect of pH, temperature, initial concentration of UO₂²⁺ ions and contact time parameters were investigated in a batch system. The particles sizes of the fungal mycelia were ranging from 100 to 200 μm. Biosorption equilibriums were established in about 30 min and the correlation regression coefficients show that the adsorption process can be well defined by the Freundlich equation. The alkali treated form had a high biosorption capacity (378 mg/g) than those of the untreated (268 mg/g) and heat-treated fungal mycelia (342 mg/g). Optimum biosorption was observed at pH 4.5 for all the tested fungal preparations and was independent of temperature (5–35 °C). In addition, the polarity and surface energy of the fungal biomass film preparations were determined by contact angle measurement. The fungal biomass could be regenerated using 10 mM sodium carbonate, with up to 93% recovery. The biosorbents were used in six biosorption–desorption cycles and no considerable loss in the biosorption capacity was observed.

Keywords: White-Rot Fungus, Lentinus Sajor-Caju, Biosorption, Uranium(VI), Chemical and Physical Treatment, Contact Angle, Surface Energy

? Wang, S.B. and Wu, H.W. (2006), Environmental-benign utilisation of fly ash as low-cost adsorbents. Journal of Hazardous Materials, 136 (3), 482-501.

Full Text: 2006\J Haz Mat136, 482.pdf

Abstract: Fly ash is a waste substance from thermal power plants, steel mills, etc. that is found in abundance in the world. In recent years, utilisation of fly ash has gained much attention in public and industry, which will help reduce the environmental burden and enhance economic benefit. In this paper, the technical feasibility of utilisation of fly ash as a low-cost adsorbent for various adsorption processes for removal of pollutants in air and water systems has been reviewed. Instead of using commercial activated carbon or zeolites, a lot of researches have been conducted using fly ash for adsorption of NOx, SOx, organic compounds, and mercury in air, and cations, anions, dyes and other organic matters in waters. It is recognised that fly ash is a promising adsorbent for removal of various pollutants. Chemical treatment of fly ash will make conversion of fly ash into a more efficient adsorbent for gas and water cleaning. Investigations also revealed that unburned carbon component in fly ash plays an important role in adsorption capacity. Directions for future research are also discussed.

Keywords: Adsorbent, Adsorbent Dosage, Adsorption, Adsorption, Adsorption Isotherms, Aqueous Solution, Aqueous Solutions, Batch, Biosorption, Capacity, Carbon, Copper(II), Data, Dynamic, Equilibrium, Experimental, Experiments, Freundlich, Heavy-Metals, Isotherm, Isotherms, Kinetic, Kinetic Model, Kinetic Models, Kinetics, Kinetics, Langmuir, Langmuir Model, Model, Models, Monolayer, Particle Size, pH, pH Value, Pseudo First Order, Pseudo Second Order, Pseudo Second Order Kinetic, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Removal, Rights, Size, Solution, Solutions, Sorption, Sorption Capacity, Tectona Grandis l.f., Value

? Ayranci, E. and Duman, O. (2006), Adsorption of aromatic organic acids onto high area activated carbon cloth in relation to wastewater purification. Journal of Hazardous Materials, 136 (3), 542-552.

Full Text: 2006\J Haz Mat136, 542.pdf

Abstract: Adsorption of aromatic organic acids: benzoic acid (BA), salicylic acid (SA), p-aminobenzoic acid (pABA) and nicotinic acid (NA), onto high area activated carbon cloth from solutions in 0.4 M H₂SO₄, in water at natural pH, in 0.1 M NaOH and also from solutions having pH 7.0 were studied by in situ UV-spectroscopic technique. The first-order rate law was found to be applicable for the kinetic data of adsorption. The rates and extents of adsorption of the organic acids were the highest from water or 0.4 M H₂SO₄ solutions and the lowest from 0.1 M NaOH solution. The order of rates and extents of adsorption of the four organic acids in each of the four solutions (0.4 M H₂SO₄, water, solution of pH 7.0 and 0.1 M NaOH) was determined as SA > BA > NA  pABA. These observed orders were explained in terms of electrostatic, dispersion and hydrogen bonding interactions between the surface and the adsorbate species, taking the charge of the carbon surface and the adsorbate in each solution into account. Adsorption of BA in molecular form or in benzoate form was analyzed by treating the solution as a mixture of two components and applying Lambert–Beer law to two-component system. The adsorption isotherm data of the systems studied were derived at 30 °C and fitted to Langmuir and Freundlich equations.

Keywords: Activated Carbon Cloth, Adsorption, Aromatic Organic Acids, UV Spectroscopy, Ionization, Wastewater Purification

? King, P., Srinivas, P., Kumar, Y.P. and Prasad, V.S.R.K. (2006), Sorption of copper(II) ion from aqueous solution by Tectona grandis l.f. (teak leaves powder). Journal of Hazardous Materials, 136 (3), 560-566.

Full Text: 2006\J Haz Mat136, 560.pdf

Abstract: Studies on a batch sorption system using Tectona grandis l.f. as adsorbent was investigated to remove copper(II) from aqueous solutions. The adsorption experiments were performed under various conditions such as different initial concentrations, pH, adsorbent dosage and adsorbent particle size. The data showed that 0.1 g of Tectona grandis l.f. was found to remove 71.66% of 20 mg/L copper(II) from 30 mL aqueous solution in 180 min. The experimental equilibrium data were adjusted by the adsorption isotherms from Langmuir and Freundlich models and their equilibrium parameters were determined. The best-adjusted model to the experimental equilibrium data for Tectona grandis l.f. was the Langmuir model. Using the Langmuir model equation, the monolayer sorption capacity of Tectona grandis l.f. was evaluated and found to be 95.40 mg/g. The optimum pH value was found to be 5.5. The pseudo-first-order and pseudo-second-order kinetic models were used to describe the kinetic data. The dynamic data fitted the pseudo-second-order kinetic model.

Keywords: Adsorbent, Adsorption, Adsorption Isotherms, Aqueous Solution, Aqueous Solutions, Batch, Capacity, Copper(II), Data, Dynamic, Equilibrium, Experimental, Experiments, Freundlich, Isotherms, Kinetic, Kinetic Model, Kinetic Models, Kinetics, Langmuir, Langmuir Model, Model, Models, Monolayer, Particle Size, pH, pH Value, Pseudo First Order, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Size, Solution, Solutions, Sorption, Sorption Capacity, Tectona Grandis l.f., Value

? Mittal, A., Mittal, J. and Kurup, L. (2006), Adsorption isotherms, kinetics and column operations for the removal of hazardous dye, Tartrazine from aqueous solutions using waste materials—Bottom Ash and De-Oiled Soya, as adsorbents. Journal of Hazardous Materials, 136 (3), 567-578.

Full Text: 2006\J Haz Mat136, 567.pdf

Abstract: Adsorbents, Bottom Ash (a power plant waste) and De-Oiled Soya (an agricultural waste) exhibit good efficacy to adsorb a highly toxic dye, Tartrazine. Through the batch technique equilibrium uptake of the dye is observed at different concentrations, pH of the solution, dosage of adsorbents and sieve size of adsorbents. Langmuir and Freundlich adsorption isotherms are successfully employed on both the adsorbents and on the basis of these models the thermodynamic parameters are evaluated. Kinetic investigations reveal that more than 50% adsorption of dye is achieved in about 1 h in both the cases, whereas, equilibrium establishment takes about 3–4 h. The linear plots obtained in rate constant and mass transfer studies further confirm the applicability of first order rate expression and mass transfer model, respectively. The kinetic data treated to identify rate controlling step of the ongoing adsorption processes indicate that for both the systems, particle diffusion process is predominant at higher concentrations, while film diffusion takes place at lower concentrations. The column studies reveal that about 96% saturation of both the columns is attained during their exhaustion, while about 88 and 84% of the dye material is recovered by eluting dilute NaOH solution through exhausted Bottom Ash and De-Oiled Soya columns, respectively.

Keywords: Adsorbents, Adsorption, Adsorption Isotherms, Agricultural, Agricultural Waste, Aqueous Solutions, Azo Dye, Batch, Bottom Ash, Column, Column Studies, Data, De-Oiled Soya, Diffusion, Dye, Efficacy, Equilibrium, Exhaustion, Expression, Film Diffusion, First, First Order, Freundlich, Investigations, Isotherms, Kinetic, Kinetics, Langmuir, Mass Transfer, Model, Models, NaOH, Particle Diffusion, pH, Plant, Power, Power Plant, Rate Constant, Removal, Saturation, Size, Solution, Solutions, Systems, Tartrazine, Thermodynamic, Thermodynamic Parameters, Toxic, Uptake, Waste, Waste Materials

? Narin, I., Surme, Y., Soylak, M. and Dogan, M. (2006), Speciation of Cr(III) and Cr(VI) in environmental samples by solid phase extraction on Ambersorb 563 resin. Journal of Hazardous Materials, 136 (3), 579-584.

Full Text: 2006\J Haz Mat136, 579.pdf

Abstract: A simple and sensitive method for the speciation, separation and preconcentration of Cr(VI) and Cr(III) in natural water, soil and sediment samples was developed. Cr(VI) has been separated from Cr(III) and preconcentrated as Cr(III)–diphenylcarbazone complex by using Ambersorb 563 resin and determined by spectrophotometric method at 540 nm. Effect of analytical parameters such as sulfuric acid concentration, ligand volume, type of elution solution, sample volume, amount of resin and foreign ions were investigated. The presented procedure was successfully applied for the chromium speciation in various environmental samples with successfully results.

Keywords: Speciation, Chromium, Ambersorb 563, Solid Phase Extraction, Spectrophotometric Determination

? Tuzen, M., Melek, E. and Soylak, M. (2006), Celtek clay as sorbent for separation–preconcentration of metal ions from environmental samples. Journal of Hazardous Materials, 136 (3), 597-603.

Full Text: 2006\J Haz Mat136, 597.pdf

Abstract: The sorption conditions including pH of the aqueous solution, sample volume, etc., on Celtek clay of copper(II), cadmium(II), Lead(II), Chromium(III), nickel(II) and cobalt(II) ions from environmental samples has been studied. The effects of electrolytes as matrix on the preconcentration were also investigated with the recoveries >95%. The 3 sigma detection limits for copper, cadmium, lead, chromium, nickel and cobalt ions were found to be 0.25, 0.32, 0.73, 0.45, 0.50 and 0.41 μg/l, respectively. The relative standard deviation was <10% for the determination of analytes. The procedure was validated by analysis of a NRCC-SLRS 4 Riverine Water, SRM 1573a Tomato leaves and IAEA 336 Lichen standard reference materials. The developed method was successively utilized for the determination of Cu(II), Cd(II), Pb(II), Cr(III), Ni(II) and Co(II) in various samples including natural waters, wheat and human hair by flame atomic absorption spectrometry (FAAS) with satisfactorily results (recoveries > 95% and R.S.D.’s < 10%).

Keywords: Celtek Clay, Preconcentration, Solid-Phase Extraction, Flame Atomic Absorption Spectrometry

? Karadag, D., Koc, Y., Turan, M. and Armagan, B. (2006), Removal of ammonium ion from aqueous solution using natural Turkish clinoptilolite. Journal of Hazardous Materials, 136 (3), 604-609.

Full Text: 2006\J Haz Mat136, 604.pdf

Abstract: A study on ion exchange kinetics and equilibrium isotherms of ammonium ion on natural Turkish clinoptilolite (zeolite) was conducted using a batch experiment technique. The effects of relevant parameters, such as temperature, contact time and initial ammonium (NH₄⁺) concentration were examined, respectively. The pseudo first-order, pseudo second-order kinetic models and intraparticle diffusion model were used to describe the kinetic data. The pseudo second-order kinetic model provided excellent kinetic data fitting (R² > 0.990) and intraparticle diffusion effects ammonium uptake. The Langmuir and Freundlich models were applied to describe the equilibrium isotherms for ammonium uptake and the Langmuir model agrees very well with experimental data. Thermodynamic parameters such as change in free energy (ΔG⁰), enthalpy (ΔH⁰) and entropy (ΔS⁰) were also determined. An examination of the thermodynamic parameters shows that the exchange of ammonium ion by clinoptilolite is a process occurring spontaneously and physical in nature at ambient conditions (25 °C). The process is also found to be exothermic. The results indicate that there is a significant potential for the natural Turkish clinoptilolite as an adsorbent material for ammonium removal from aqueous solutions.

Keywords: Adsorbent, Ammonium, Ammonium Removal, Aqueous Solution, Aqueous Solutions, Batch, Clinoptilolite, Concentration, Data, Diffusion, Diffusion Model, Energy, Enthalpy, Entropy, Equilibrium, Examination, Exothermic, Experiment, Experimental, First Order, Freundlich, Intraparticle Diffusion, Intraparticle Diffusion Model, Ion Exchange, Ion-Exchange, Isotherm, Isotherms, Kinetic, Kinetic Model, Kinetic Models, Kinetics, Langmuir, Langmuir Model, Model, Models, Physical, Potential, Pseudo First Order, Pseudo First-Order, Pseudo Second Order, Pseudo Second-Order, Pseudo-First-Order, Pseudo-Second-Order, Removal, Second Order, Second-Order, Solution, Solutions, Temperature, Thermodynamic, Thermodynamic Parameter, Thermodynamic Parameters, Uptake, Zeolite

? Kwon, T.S., Yang, J.S., Baek, K., Lee, J.Y. and Yang, J.W. (2006), Silicone emulsion-enhanced recovery of chlorinated solvents: Batch and column studies. Journal of Hazardous Materials, 136 (3), 610-617.

Full Text: 2006\J Haz Mat136, 610.pdf

Abstract: Batch and column experiments were conducted to investigate the feasibility of flushing with silicone oil emulsion for the removal of chlorinated solvents, including trichloroethylene (TCE), perchloroethylene (PCE) and 1,2-dichlorobenzene (DCB). In the batch experiments, solubilization potentials of emulsion and effects of surfactants as additives were examined. The emulsion prepared with 2% (v/v) silicone oil could solubilize 90.7% of 10,000 ppm TCE, 97.3% of 4000 ppm PCE and 99.7% of 7800 ppm DCB. Results of one-dimensional column studies indicated that aqueous solubility and sorption of contaminants determined the flushing efficiency. The addition of surfactants below their critical micelle concentration (CMC) did not affect the removal of chlorinated solvents in batch and column experiments. The results of this study show that flushing with oil-based emulsion can be applied to treat the chlorinated solvents.

Keywords: Emulsion, Chlorinated Solvents, Flushing, Remediation

? Singh, S.P., Ma, L.Q. and Hendry, M.J. (2006), Characterization of aqueous lead removal by phosphatic clay: Equilibrium and kinetic studies. Journal of Hazardous Materials, 136 (3), 654-662.

Full Text: 2006\J Haz Mat136, 654.pdf

Abstract: Immobilization of heavy metals from contaminated environments is an emerging field of interest from both resource conservation and environmental remediation points of view. This study investigated the feasibility of using phosphatic clay, a waste by-product of the phosphate mining industry, as an effective sorbent for Pb from aqueous effluents. The major parameters controlling aqueous Pb removal, viz. initial metal ion concentrations, solution pH, sorbent amounts, ionic strength and presence of both inorganic and organic ligands were evaluated using batch experiments. Results demonstrated that aqueous Pb removal efficiency of phosphatic clay is controlled mainly by dissolution of phosphatic clay associated fluoroapatite [Ca₁₀(PO₄)₅CaCO₃(F,Cl,OH)₂], followed by subsequent precipitation of geochemically stable pyromorphite [Pb₁₀(PO₄)₆(F,Cl,OH)₂], which was confirmed by both X-ray diffraction (XRD) and scanning electron microscopic (SEM) analysis. Lead removal efficiency of phosphatic clay increased with increasing pH, sorbent amount and decreasing ionic strength. It also depends on the nature of complexing ligands. Formation of insoluble calcium oxalate and lead oxalate in the presence of oxalic acid explained high uptake of Pb by phosphatic clay from aqueous solution. However, Pb sorption kinetics onto phosphatic clay were biphasic, with initially fast reactions followed by slow and continuous Pb removal reactions. The slow reactions may include surface sorption, co-precipitation and diffusion. The exceptional capability of phosphatic clay to remove aqueous Pb demonstrated its potential as a cost effective way to remediate Pb-contaminated water, soils and sediments.

Keywords: Phosphatic Clay, Lead, Sorption Isotherms, pH, Ligand, Sorption Kinetics

? Tseng, R.L. and Tseng, S.K. (2006), Characterization and use of high surface area activated carbons prepared from cane pith for liquid-phase adsorption. Journal of Hazardous Materials, 136 (3), 671-680.

Full Text: 2006\J Haz Mat136, 671.pdf

Abstract: Carbonaceous adsorbents with controllable surface areas were chemically activated with KOH at 780 °C from char that had been carbonized from cane pith at 450 °C. The pore properties including the BET surface area, pore volume, pore size distribution, and mean pore diameter of these activated carbons were characterized and derived using the t-plot method based on N₂ adsorption isotherms. The activated cane pith carbons, with KOH/char ratios of 2–6, exhibited BET surface areas ranging from 912 to 2299 m² g⁻¹. The scanning electron microscopic (SEM) observations revealed that the surface morphology of honeycombed holes on all activated cane pith carbons was significantly influenced by the KOH/char ratio. The adsorption kinetics and equilibrium isotherms of acid blue 74, methylene blue, basic brown 1, p-nitrophenol, p-chlorophenol, p-cresol, and phenol from water at 30 °C on the activated carbons were studied. The adsorption kinetics were suitably described by a simplified kinetic model, the Elovich equation. All adsorption equilibrium isotherms were in agreement with the Langmuir equation, and were used to compare the covered area (Sc/Sp) of the activated carbons at different KOH/char ratios. The high-surface-area activated carbons were proven to be promising adsorbents for pollution control and for other applications.

Keywords: Activated Carbons, KOH Activation, Cane Piths, Pore properties, Adsorption

? Ho, Y.S. (2006), Review of second-order models for adsorption systems. Journal of Hazardous Materials, 136 (3), 681-689.

Full Text: 2006\J Haz Mat136, 681.pdf; 2006\J Haz Mat-Ho.pdf; 2006\J Haz Mat-Ho1.pdf

Abstract: Applications of second-order kinetic models to adsorption systems were reviewed. An overview of second-order kinetic expressions is described in this paper based on the solid adsorption capacity. An early empirical second-order equation was applied in the adsorption of gases onto a solid. A similar second-order equation was applied to describe ion exchange reactions. In recent years, a pseudo-second-order rate expression has been widely applied to the adsorption of pollutants from aqueous solutions onto adsorbents. In addition, the earliest rate equation based on the solid adsorption capacity is also presented in detail. (c) 2006 Elsevier B.V. All rights reserved.

Keywords: Adsorbents, Adsorption, Adsorption Capacity, Aqueous Solutions, Biosorption, Capacity, Expression, Ion Exchange, Ion-Exchange, Kinetic, Kinetic Models, Kinetics, Models, Pollutants, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Rate, Second Order, Second-Order, Second-Order Equation, Solutions, Sorption, Systems

? Kumar, K.V. and Sivanesan, S. (2006), Pseudo second order kinetics and pseudo isotherms for malachite green onto activated carbon: Comparison of linear and non-linear regression methods. Journal of Hazardous Materials, 136 (3), 721-726.

Full Text: 2006\J Haz Mat136, 721.pdf

Abstract: Pseudo second order kinetic expressions of Ho, Sobkowsk and Czerwinski, Blanachard et al. and Ritchie were fitted to the experimental kinetic data of malachite green onto activated carbon by non-linear and linear method. Non-linear method was found to be a better way of obtaining the parameters involved in the second order rate kinetic expressions. Both linear and non-linear regression showed that the Sobkowsk and Czerwinski and Ritchie’s pseudo second order model were the same. Non-linear regression analysis showed that both Blanachard et al. and Ho have similar ideas on the pseudo second order model but with different assumptions. The best fit of experimental data in Ho’s pseudo second order expression by linear and non-linear regression method showed that Ho pseudo second order model was a better kinetic expression when compared to other pseudo second order kinetic expressions. The amount of dye adsorbed at equilibrium, qe, was predicted from Ho pseudo second order expression and were fitted to the Langmuir, Freundlich and Redlich Peterson expressions by both linear and non-linear method to obtain the pseudo isotherms. The best fitting pseudo isotherm was found to be the Langmuir and Redlich Peterson isotherm. Redlich Peterson is a special case of Langmuir when the constant g equals unity.

Keywords: Activated Carbon, Adsorption, Adsorption, Analysis, Assumptions, Carbon, Data, Dye, Equilibrium, Experimental, Expression, Freundlich, Isotherm, Isotherms, Kinetic, Kinetics, Langmuir, Linear Method, Linear Regression, Malachite Green, Methods, Model, Non-Linear, Non-Linear Method, Non-Linear Regression, Nonlinear Regression, Pseudo, Pseudo Second Order, Pseudo Second Order Kinetic, Pseudo Second Order Kinetics, Pseudo-Isotherm, Pseudo-Second-Order, Redlich-Peterson, Regression, Regression Analysis, Rights, Second Order, Second Order Kinetics, Second-Order, Solids, Sorption

? Wang, Y.Q., Liu, S.J., Xu, Z., Han, T.W., Chuan, S. and Zhu, T. (2006), Ammonia removal from leachate solution using natural Chinese clinoptilolite. Journal of Hazardous Materials, 136 (3), 735-740.

Full Text: 2006\J Haz Mat136, 735.pdf

Abstract: This paper assesses the potential of natural Chinese clinoptilolite for ammonia removal from the leachate solution of sewage sludge. In batch study the effects of relevant parameters, such as contact time, initial ammonia concentration and particle size of clinoptilolite, were examined respectively. The results show that the data obtained from batch studies were fit to Langmuir and Freundlich isotherms and the Langmuir isotherms reflect more reasonable for ammonium ion uptake onto clinoptilolite; the clinoptilolite adsorption process has been proved effective, at laboratory scale, the maximum adsorption capacity of the clinoptilolite, for ammonium concentration ranging from 11.12 to 115.16 mg NH₄–N L⁻¹ in leachate solution, was about 1.74 mg NH₄–N g⁻¹; the time to adsorption equilibrium was 2.5 h in leachate solution and 1.5 h more than for in NH₄Cl synthetic solution; ammonium adsorption increased with decreasing clinoptilolite particle size; the ammonia removal capacity of clinoptilolite increased with increasing initial ammonia concentration. It is believed that as adsorption agent for NH₄–N removal from sludge leachate, natural Chinese clinoptilolite can be feasible.

Keywords: Ammonia Removal, Capacity, Clinoptilolite, Leachate, Sewage Sludge

? Hubicki, Z. and Wójcik, G. (2006), Studies of removal of platinum(IV) ion microquantities from the model solutions of aluminium, copper, iron, nickel and zinc chloride macroquantities on the anion exchanger Duolite S 37. Journal of Hazardous Materials,