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137 (1), 396-400.

Full Text: 2006\J Haz Mat137, 396.pdf

Abstract: Adsorptive removal of water poisons such as Pb(II), Cu(II), Mn(II), Hg(II), CN, microbes, nerve and blister agents (concentration range from 100 to 1000 mg/L) were studied by using adsorbents such as active carbon, impregnated carbon and bentonite loaded fabric strip. Removal of water poisons (99.5%) could be achieved with an optimum stirring time of 5–15 min and weight of adsorbent of 0.8–8.0 g/100 mL contaminated water, respectively. However, 85% bentonite loading was found to be most effective for Pb(II) removal. Effect of contaminants concentration was also studied.

Keywords: Activated Carbon, Adsorption, Cyanide, Heavy Metals, Nerve and Blister Agents, Microbes

? Chai, X.L. and Zhao, Y.C. (2006), Adsorption of phenolic compound by aged-refuse. Journal of Hazardous Materials, 137 (1), 410-417.

Full Text: 2006\J Haz Mat137, 410.pdf

Abstract: The adsorption of phenol, 2-chlorophenol, 4-chlorophenol and 2,4-d ichlorophenol by aged-refuse has been studied. Adsorption isotherms have been determined for phenol, 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol and the data fits well to the Freundlish equation. The chlorinated phenols are absorbed more strongly than the phenol and the adsorption capacity has an oblivious relationship with the numbers and the position of chlorine subsistent. The experiment data suggests that both the partition function and the chemical adsorption invo lve in the adsorption process. Pseudo-first order and pseudo-second order model were applied to investigate the kinetics of the dsorption and the results show that it fit the pseudo-second order model. More than one step involves in the adsorption process and the overall rate of the adsorption process appears to be controlled by the chemical reaction. The thermodynamic analysis indicates that the adsorption is spontaneous and endothermic.

Keywords: 2,4-Dichlorophenol, 2-Chlorophenol, 4-Chlorophenol, Adsorption, Adsorption Capacity, Adsorption Isotherms, Analysis, Biofilter, Capacity, Chemical, Chlorine, Data, Endothermic, Experiment, Freundlich, Freundlich Equation, Function, Isotherms, Kinetics, Model, Phenol, Phenols, Pseudo Second Order, Pseudo-First-Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Refuse, Thermodynamic

? Aksu, Z. and Isoglu, I.A. (2006), Use of agricultural waste sugar beet pulp for the removal of Gemazol Turquoise Blue-G reactive dye from aqueous solution. Journal of Hazardous Materials, 137 (1), 418-430.

Full Text: 2006\J Haz Mat137, 418.pdf

Abstract: The potential use of dried sugar beet pulp, an agricultural solid waste by-product, as an biosorbent for Gemazol Turquoise Blue-G, a copper-phtlalocyanine reactive dye commonly used in dyeing of cotton, was investigated in the present study. Batch adsorption studies were carried out to examine the influence of various parameters such as initial pH, temperature and initial dye concentration. The results indicated that adsorption was strongly pH-dependent and slightly temperature-dependent. At 800 mg l-1 initial Gemazol Turquoise Blue-G concentration, dried sugar beet pulp exhibited the highest Gemazol Turquoise Blue-G uptake capacity of 234.8 mg g-1 at 25C and at an initial pH value of 2.0. The Freundlich, Langmuir, Redlich-Peterson and Langmuir-Freundlich, the two and three parameters adsorption models were used for the mathematical description of the biosorption equilibrium and isotherm constants were evaluated depending on temperature. Both the Langmuir and Redlich-Peterson models were applicable for describing the dye biosorption by dried sugar beet pulp in the concentration (100-800 mg l-1) and temperature (25-45C) ranges studied. Simple mass transfer and kinetic models were applied to the experimental data to examine the mechanisms of biosorption and potential rate controlling steps such as external mass transfer, intraparticle diffusion and biosorption process. The sorption process was found to be controlled by both surface and pore diffusion with surface diffusion at the earlier stages followed by pore diffusion at the later stages. Pseudo first-order, pseudo second-order and saturation type kinetic models described the biosorption kinetics accurately at all concentrations and temperatures studied. The thermodynamic analysis indicated that the sorption process was exothermic and the biosorption of dye on dried sugar beet pulp might be physical in nature.

Keywords: Activated Carbon, Adsorption, Agricultural, Agricultural Solid Waste, Agricultural Waste, Analysis, Aqueous Solution, Batch Adsorption, Biosorbent, Biosorption, Biosorption, Biosorption Equilibrium, Biosorption Kinetics, Capacity, Concentration, Controlled, Data, Diffusion, Dried Sugar Beet Pulp, Dye, Dye Biosorption, Dyestuffs, Equilibrium, Exothermic, Experimental, First Order, Freundlich, Gemazol Turquoise Blue-G, Influence, Intraparticle, Intraparticle Diffusion, Isotherm, Isotherms, Kinetic, Kinetic Models, Kinetics, Langmuir, Langmuir-Freundlich, Mass, Mass Transfer, Mechanisms, Models, pH, pH Value, Ph-Dependent, Physical, Pore Diffusion, Potential, Process, Pseudo, Pseudo First-Order, Pseudo Second Order, Pseudo Second-Order, Pseudo-First-Order, Pseudo-Second-Order, Reactive Dye, Redlich-Peterson, Remediation, Removal, Residues, Rights, Saturation, Second Order, Second-Order, Solid Waste, Solution, Sorption, Sorption Process, Sugar, Sugar Beet Pulp, Surface, Surface Diffusion, Temperature, Textile Effluent, Thermodynamic, Transfer, Uptake, Uptake Capacity, Value, Waste, Wastewaters, Water

? Kurniawan, T.A., Lo, W.H. and Chan, G.Y.S. (2006), Degradation of recalcitrant compounds from stabilized landfill leachate using a combination of ozone-GAC adsorption treatment. Journal of Hazardous Materials, 137 (1), 443-455.

Full Text: 2006\J Haz Mat137, 443.pdf

Abstract: Laboratory experiments were undertaken to investigate the treatment performances of ozonation alone and/or its combination with granular activated carbon (GAC) adsorption for raw leachate from the NENT landfill (in Hong Kong). To improve its removal of recalcitrant contaminants from the leachate, the surface of GAC was oxidized with ozone prior to treatment. With respect to ozone dose and pH, the removal of COD and/or NH3-N from ozonation alone and combined ozone-GAC adsorption were evaluated and compared to those of other physico-chemical treatments in some reported studies. The removal mechanism of recalcitrant compounds by ozone-GAC adsorption treatment was presented. Among the various treatments studied, the combination of ozone-GAC adsorption using ozone-modified GAC had the highest removal for COD (86%) and/or NH3N (92%) compared to ozonation alone (COD: 35%; NH3-N: 50%) at the same initial COD and/or NH3-N concentrations of 8000 and 2620mg/L, respectively. Although the integrated treatment was more effective than ozonation alone for treating stabilized leachate, the results suggested that it could not generate treated effluent that complied with the COD limit of lower than 200 mg/L and the NH3-N discharge standard of less than 5 mg/L. Therefore, further biological treatments to complement the degradation of the leachate are still required to meet the environmental legislation. (c) 2006 Elsevier B.V. All rights reserved.

Keywords: 1,3,6-Naphthalenetrisulphonic Acid, Activated Carbon, Activated Carbon Treatment, Adsorption, Advanced Oxidation Process (AOP), Advanced Oxidation Processes, Aqueous-Phase, Biological, Carbon, Catalytic Ozonation, Cod, Contaminants, Degradation, Discharge, Environmental, Experiments, Gac, Granular Activated Carbon, Hong Kong, Landfill, Landfill Leachate, Landfill Leachate Management, Leachate, Legislation, Mechanism, Municipal Solid Waste, Nh3-N, Non-Biodegradable Compounds, Oh-Radicals, Ozone, pH, Physico-Chemical Treatments, Precipitation, Recalcitrant Compounds, Removal, Removal Mechanism, Reverse-Osmosis, Rights, Standard, Surface, Treatment, Waste-Water Treatment

? Meenakshi, S. and Maheshwari, R.C. (2006), Fluoride in drinking water and its removal. Journal of Hazardous Materials, 137 (1), 456-463.

Full Text: 2006\J Haz Mat137, 456.pdf

Abstract: Excessive fluoride concentrations have been reported in groundwaters of more than 20 developed and developing countries including India where 19 states are facing acute fluorosis problems. Various technologies are being used to remove fluoride from water but still the problem has not been rooted out. In this paper, a broad overview of the available technologies for fluoride removal and advantages and limitations of each one have been presented based on literature survey and the experiments conducted in the laboratory with several processes. It has been concluded that the selection of treatment process should be site specific as per local needs and prevailing conditions as each technology has some limitations and no one process can serve the purpose in diverse conditions. (c) 2006 Published by Elsevier B.V.

Keywords: Fluoride, Fluorosis, Ground Water, Soil Water, Drinking Water, Treatment, Bipolar Aluminum Electrodes, Donnan Dialysis, Sahara Water, Defluoridation, Groundwater, Contamination, Adsorption, History

? Han, R.P., Lu, Z., Zou, W.H. Wang, D.T., Shi, J. and Yang, J.J. (2006), Removal of copper(II) and Lead(II) from aqueous solution by manganese oxide coated sand. II. Equilibrium study and competitive adsorption. Journal of Hazardous Materials, 137 (1), 480-488.

Full Text: 2006\J Haz Mat137, 480.pdf

Abstract: The adsorption equilibrium of MOCS and the Cu(II) and Pb(II) ions removal capacity by MOCS in single-(non-competitive) and binary-(competitive) component sorption systems from aqueous solutions were investigated. The equilibrium data were analyzed using the Langmuir, Freundlich, Temkin and Redlich–Peterson isotherms. The characteristic parameters for each isotherm were determined. The Langmuir and Redlich–Peterson isotherms provided the best correlation for both Cu(II) and Pb(II) onto MOCS. From the Langmuir isotherms, maximum adsorption capacities of MOCS towards Cu(II) and Pb(II) are determined at different temperature. The maximum adsorption capacity of Cu(II) and Pb(II) per gram MOCS in single component sorption systems were from 5.91 and 7.71 μmol to 7.56 and 9.22 μmol for the temperature range of 288–318 K, respectively. The order of affinity based on a weight uptake by MOCS was as follows: Pb(II) > Cu(II). The same behavior was observed during competitive adsorption that is in the case of adsorption from their binary solution. The thermodynamic parameters (ΔG°, ΔH°, and ΔS°) for Cu(II) and Pb(II) sorption on MOCS were also determined from the temperature dependence. This competitive adsorption showed that the uptake of each metal was considerably reduced with an increasing concentration of the other, the adsorption of Cu(II) being more strongly influenced by Pb(II) than vice versa due to the higher affinity of MOCS for the latter.

Keywords: Adsorbent, Adsorption, Adsorption Capacities, Adsorption Capacity, Adsorption Equilibrium, Aqueous Solution, Aqueous Solutions, Behavior, Biosorption, Capacity, Competitive Adsorption, Concentration, Copper(II), Correlation, Cu(II), Data, Equilibrium, Freundlich, Ions, Isotherm, Isotherms, Langmuir, Langmuir Isotherms, Lead(II), Manganese, Manganese Oxide, Manganese Oxide Coated, Manganese Oxide Coated Sand (MOCS), Metal, Metals, Oxide, Pb(II), Pb(II) Ions, Redlich-Peterson, Removal, Rights, Sand, Solution, Solutions, Sorption, Systems, Temperature, Thermodynamic, Thermodynamic Parameters, Uptake, US

? Wu, J. and Yu, H.Q. (2006), Biosorption of 2,4-dichlorophenol from aqueous solution by Phanerochaete chrysosporium biomass: Isotherms, kinetics and thermodynamics. Journal of Hazardous Materials, 137 (1), 498-508.

Full Text: 2006\J Haz Mat137, 498.pdf

Abstract: The biosorption of 2,4-dichlorophenol (2,4-DCP) from aqueous solution on non-living mycelial pellets of Phanerochaete chrysosporium was studied with respect to pH, initial concentration of 2,4-DCP, temperature and pellet size. The fungal biomass exhibited the highest sorption capacity of 4.09 mg/g at an initial pH of 5.0, initial 2,4-DCP concentration of 50.48 mg/l, 25C and a pellet size of 1.0-1.5 mm in the investigated pH 2.0-11.0, initial concentrations of 5-50 mg/l, temperature 25C-50C, and pellet size of 1.0 mm-2.5 mm. The Freundlich model exhibited a slightly better fit to the biosorption data of 2,4-DCP than the Langmuir model. The biosorption of 2,4-DCP to biomass followed pseudo second-order adsorption kinetics. The second-order kinetic constants decreased with increasing temperature, and the apparent activation energy of biosorption was estimated to be –16.95 kJ/mol. The thermodynamic analysis indicates that the biosorption process was exothermic and that the adsorption of 2,4-DCP on P. chrysosporium might be physical in nature. Both intraparticle diffusion and kinetic resistances might affect the adsorption rate and that their relative effects varied with operation temperature in the biosorption of 2,4-DCP by mycelial pellets.

Keywords: 2,4-DCP, 2,4-Dichlorophenol, Activation, Activation Energy, Adsorption, Adsorption Kinetics, Adsorption Rate, Analysis, Aqueous Solution, Biomass, Biosorption, Capacity, Concentration, Data, Diffusion, Energy, Equilibrium Isotherm, Exothermic, Freundlich, Freundlich Model, Fungal Biomass, Intraparticle Diffusion, Isotherms, Kinetic, Kinetics, Kinetics and Thermodynamics, Langmuir, Langmuir Model, Model, Mycelial Pellets, Non-Living, Operation, P, Pellet, pH, Phanerochaete Chrysosporium, Physical, Pseudo Second Order, Pseudo Second-Order, Pseudo-Second-Order, Second Order, Second-Order, Size, Solution, Sorption, Sorption Capacity, Temperature, Thermodynamic, Thermodynamics

? Pavan, F.A., Lima, I.S., Lima, É.C., Airoldi, C. and Gushikem, Y. (2006), Use of Ponkan mandarin peels as biosorbent for toxic metals uptake from aqueous solutions. Journal of Hazardous Materials, 137 (1), 527-533.

Full Text: 2006\J Haz Mat137, 527.pdf

Abstract: Waste Ponkan mandarin (Citrus reticulata) peel was used as biosorbent to extract Ni(II), Co(II) and Cu(II) from aqueous solutions at room temperature. To achieve the best adsorption conditions the influence of pH and contact time were investigated. The isotherms of adsorption were fitted to the Langmuir equation. Based on the capacity of adsorption of the natural biosorbent to interact with the metallic ions, the following results were obtained 1.92, 1.37 and 1.31 mmol g−1 for Ni(II), Co(II) and Cu(II), respectively, reflecting a maximum adsorption order of Ni(II) > Co(II) > Cu(II). The quick adsorption process reached the equilibrium before 5, 10 and 15 min for Ni(II), Co(II) and Cu(II), respectively, with maximum adsorptions at pH 4.8. In order to evaluate the Ponkan mandarin peel a biosorbent in dynamic system, a glass column was fulfilled with 1.00 g of this natural adsorbent, and it was feed with 5.00×10−4 mol l−1 of Ni(II) or Co(II) or Cu(II) at pH 4.8 and 3.5 ml min−1. The lower breakpoints (BP1) were attained at concentrations of effluent of the column attained the maximum limit allowed of these elements in waters (>0.1 mg l−1) which were: 110, 100 and 130 bed volumes (Veffluent/Vadsorbent), for Ni(II), Co(II) and Cu(II), respectively. The higher breakpoints (BP2) were attained when the complete saturation of the natural adsorbent occurred, and the values obtained were: 740, 540 and 520 bed volumes for Ni(II), Co(II) and Cu(II), respectively.

Keywords: Biosorbent, Ponkan Mandarin Peel, Adsorption, Toxic Metals, Aqueous Solutions, Batch, Dynamic Adsorption Procedures

? Han, R.P., Wang, Y.F., Han, P., Shi, J., Yang, J. and Lu, Y.S. (2006), Removal of methylene blue from aqueous solution by chaff in batch mode. Journal of Hazardous Materials, 137 (1), 550-557.

Full Text: 2006\J Haz Mat137, 550.pdf

Abstract: A new adsorbent system for removing methylene blue (MB) from aqueous solutions has been investigated. This new adsorbent is cereal chaff, an agriculture product in middle-west region in China. Variables of the system, including biosorption time, chaff dose, pH, salt concentration and initial MB concentration, were adopted to study their effects on MB removal. The results showed that as the dose of chaff increased, the percentage of MB sorption increased accordingly. There was no significant difference in the dye concentration remaining when the pH was increased from 4.0 to 11.0. The salt concentration has negative effect on MB removal. At the experimental range of MB concentration, the amount of MB adsorbed onto per unit mass of chaff (qe) is direct ratio to MB initial concentration (c0). The equilibrium data were analyzed using five equilibrium models, the Langmuir, the Freundlich, the Redlich–Peterson, the Koble–Corrigan and the Temkin isotherms. The results of non-linear regressive analysis are that the isotherms of Langmuir, Redlich–Peterson and Koble–Corrigan are better fit than the isotherms of Freundlich and Temkin at different temperatures according to the values of determined coefficients (R2) and Chi-square statistic (χ2). The maximum equilibrium capacities of chaff from Langmuir models are 20.3, 25.3 and 26.3 mg g−1 at 298, 318 and 333 K, respectively. Using the equilibrium concentration constants obtained at different temperatures, various thermodynamic parameters, such as ΔG0, ΔH0 and ΔS0, have been calculated. The thermodynamics parameters of MB/chaff system indicate spontaneous and endothermic process. It was concluded that an increase in temperature results in a bigger MB loading per unit weight of the chaff.

Keywords: Chaff, Biosorption, Methylene Blue, Equilibrium, Thermodynamic

? Vijayaraghavan, K. and Prabu, D. (2006), Potential of Sargassum wightii biomass for copper(II) removal from aqueous solutions: Application of different mathematical models to batch and continuous biosorption data. Journal of Hazardous Materials, 137 (1), 558-564.

Full Text: 2006\J Haz Mat137, 558.pdf

Abstract: This paper reports biosorption of copper(II) ions onto Sargassum wightii biomass in batch and continuous mode of operation. Batch experiments were fundamentally aimed to determine the favorable pH for copper(II) biosorption. Langmuir model was used to describe the copper(II) biosorption isotherm and maximum uptake of 115 mg/g was obtained at pH 4.5. Continuous experiments in a packed column (2 cm i.d. and 35 cm height) were performed to study the influence of bed height, flow rate and inlet solute concentration on copper(II) biosorption. The highest bed height (25 cm), lowest flow rate (5 ml/min) and highest inlet Cu(II) concentration (100 mg/l) resulted in highest copper(II) uptake of 52.6 mg/g, compared to other conditions examined. Column data obtained at different conditions were described using the Thomas, Yoon–Nelson and modified dose–response models. All three models were able to predict breakthrough curves; in particular, the breakthrough curve prediction by the Thomas and Yoon–Nelson models were found to be very satisfactory. Also, the well-established design model, the Bed depth–service time (BDST) model was used to analyze the experimental data. The BDST model plot at 5 ml/min (flow rate) and 100 mg/l (inlet solute concentration) was used to predict bed depth–service time data at different conditions. The BDST model predicted values always coincide with experimental values with high correlation coefficients.

Keywords: Biosorption, Sargassum wightii, Mathematical Modeling, Packed Column, Copper

? Mittal, A., Mittal, J. and Kurup, L. (2006), Batch and bulk removal of hazardous dye, indigo carmine from wastewater through adsorption. Journal of Hazardous Materials, 137 (1), 591-602.

Full Text: 2006\J Haz Mat137, 591.pdf

Abstract: An inexpensive adsorption method has been developed for the removal of indigo carmine, a highly toxic indigoid class of dye from wastewater. Waste materials—bottom ash, a power plant waste and de-oiled soya, an agricultural waste have been used as adsorbents. Attempts have been made through batch and bulk removal of the dye and both the adsorbents have been found to exhibit good efficiency to adsorb indigo carmine. Under batch technique effect of temperature, pH, concentration, dosage of adsorbents, sieve size of adsorbents, etc. have been observed. The dye uptake on to both the adsorbents is found to validate Langmuir and Freundlich adsorption isotherms models. Different thermodynamic parameters, like Gibb’s free energy, enthalpy and entropy of the on-going adsorption process have also been evaluated. Batch technique has also been employed for the kinetic measurements and the adsorption follows a first order rate kinetics for both the adsorbents. The kinetic investigations also reveal for both the adsorbents film diffusion and particle diffusion mechanisms are operative in the lower and higher concentration ranges, respectively. Under the bulk removal, indigo carmine has been adsorbed through the column beds of bottom ash and de-oiled soya and more than 90% of the dye material has been recovered by eluting dilute NaOH solution through exhausted columns.

Keywords: Adsorbents, Adsorption, Adsorption Isotherms, Adsorption Process, Agricultural, Agricultural Waste, Batch, Bottom Ash, Column, Concentration, De-Oiled Soya, Deoiled Soya, Diffusion, Dye, Efficiency, Energy, Enthalpy, Entropy, Film Diffusion, First, First Order, Freundlich, Indigo Carmine, Investigations, Isotherms, Kinetic, Kinetics, Langmuir, Mechanisms, Models, NaOH, Operative, Particle Diffusion, pH, Plant, Power, Power Plant, Rate Kinetics, Removal, Size, Solution, Temperature, Thermodynamic, Thermodynamic Parameters, Toxic, Uptake, Waste, Waste Materials, Wastewater

? Namane, A. and Hellal, A. (2006), The dynamic adsorption characteristics of phenol by granular activated carbon. Journal of Hazardous Materials, 137 (1), 618-625.

Full Text: 2006\J Haz Mat137, 618.pdf

Abstract: The objective of the present work is to determine the operating conditions of an activated carbon filter, based on the characteristics of breakthrough curves. For this we apply the technical developed by Mickaels [1] for the ionic exchange and applied by Luchkis [2] for the adsorption, and which is the mass transfer zone. To reach our goal, an evaluation of the operating conditions (height of the bed, flow and concentration of effluent) on the characteristics of the mass transfer zone was made and an explanation of the mechanism of adsorption was given. Thereafter a modeling of the experimental results was done.

Keywords: Adsorption, Activated Carbon, Phenol, Wastewater Treatment, Mathematical Model

? Özverdi, A. and Erdem, M. (2006), Cu2+, Cd2+ and Pb2+ adsorption from aqueous solutions by pyrite and synthetic iron sulphide. Journal of Hazardous Materials, 137 (1), 626-632.

Full Text: 2006\J Haz Mat137, 626.pdf

Abstract: In this study, removal of Cu2+, Cd2+ and Pb2+ from aqueous solutions by adsorption onto pyrite and synthetic iron sulphide (SIS) was investigated as a function of pH, contact time, adsorbent dosage, initial metal concentration and temperature. It has been determined that the adsorption of metal ions onto both adsorbents is pH dependent and the adsorption capacities increase with the increasing temperature. The mechanisms governing the metal removal processes were determined as chemical precipitation at low pH (<3) due to H2S generation and adsorption at high pH (in the range of 3–6). The metal adsorption yields also increased with the increasing adsorbent dosage and contact time and reached to equilibrium for both adsorbents. The Cu2+, Cd2+ and Pb2+ adsorption capacities of both adsorbents decrease in the order of Pb2+ > Cu2+ > Cd2+. Except for cadmium, little fraction of copper and lead in the solid adsorption residues was desorbed in acidic media.

Keywords: Heavy Metal, Chemical Precipitation, Adsorption, Desorption, Pyrite, Iron Sulphide

? Kumar, K.V. (2006), Comments on “Adsorption of acid dye onto organobentonite”. Journal of Hazardous Materials,



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