Personal Research Database

Full Text: 2010\J Haz Mat176, 374.pdf

Abstract: The feasibility of using a solid waste (rich in nitrogen) from the leather industry, after chromium extraction, as adsorbent for P and K, for possible utilization as NPK fertilizer was evaluated. The materials, with and without the addition of P and K, were characterized by chemical analyses, infrared spectroscopy, EDS (energy dispersive X-ray spectrometry) and SEM (scanning electronic microscopy). Langmuir and Freundlich equations were used for analyzing the experimental data, which showed a better fit to the Freundlich model, thus suggesting a multilayer adsorption process on the surface of the adsorbent. A preliminary test in greenhouse demonstrates that the P and K incorporation on the matrix rich in nitrogen (collagen) is a interesting alternative to use such material as NPK fertilizer. The application of NcollagenPK formulations, as a source of nutrients for the growth of rice plants, showed promising agronomic results. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Chromium, Chromium, Freundlich, Industry, Infrared, Langmuir, Leather Waste, Macronutrients, Ncollagenpk Formulation, Removal, SEM, Solid-Waste, Water

? Viswanathan, N. and Meenakshi, S. (2010), Development of chitosan supported zirconium(IV) tungstophosphate composite for fluoride removal. Journal of Hazardous Materials, 176 (1-3), 459-465.

Full Text: 2010\J Haz Mat176, 459.pdf

Abstract: A new biocomposite was prepared by incorporating inorganic ion exchanger namely zirconium(IV) tungstophosphate (ZrWP) into the chitosan biopolymeric matrix. The sorption behaviour of fluoride from aqueous solutions by this ZrWP/chitosan (ZrWPCs) composite has been investigated by batch technique. The fluoride sorption was studied as a function of contact time, pH, initial fluoride concentration, competing co-ions and temperature. The defluoridation capacity (DC) of the adsorbent was found to be 2025 mgF(-) kg^-1. The composite was characterized using FTIR and SEM with EDAX analysis. The equilibrium sorption data were fitted to Freundlich and Langmuir isotherms. The kinetics of sorption was found to follow pseudo-second-order and intraparticle diffusion models. The values of thermodynamic parameters indicate the nature of sorption is spontaneous and endothermic. The biocomposite was successfully used for the removal of fluoride from the field water taken in a nearby fluoride endemic village. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Analysis, Aqueous Solutions, Batch, Beads, Behavior, Behaviour, Capacity, Chitosan, Composite, Concentration, Data, DC, Defluoridation, Diffusion, Drinking-Water, Edax, Endothermic, Equilibrium, Field, Fluoride, Fluoride Removal, Freundlich, FTIR, Function, Intraparticle Diffusion, Isotherms, Kinetics, Langmuir, Langmuir Isotherms, Matrix, Models, pH, Pseudo Second Order, Pseudo-Second-Order, Removal, Rights, SEM, Solutions, Sorption, Sorption, Surface, Temperature, Thermodynamic, Thermodynamic Parameters, Time, Water, Zirconium(IV) Tungstophosphate

? Su, T.Z., Guan, X.H., Tang, Y.L., Gu, G.W. and Wang, J.M. (2010), Predicting competitive adsorption behavior of major toxic anionic elements onto activated alumina: A speciation-based approach. Journal of Hazardous Materials, 176 (1-3), 466-472.

Full Text: 2010\J Haz Mat176, 466.pdf

Abstract: Toxic anionic elements such as arsenic, selenium, and vanadium often co-exist in groundwater. These elements may impact each other when adsorption methods are used to remove them. In this study, we investigated the competitive adsorption behavior of As(V), Se(IV), and V(V) onto activated alumina under different pH and surface loading conditions. Results indicated that these anionic elements interfered with each other during adsorption. A speciation-based model was developed to quantify the competitive adsorption behavior of these elements. This model could predict the adsorption data well over the pH range of 1.5-12 for various surface loading conditions, using the same set of adsorption constants obtained from single-sorbate systems. This model has great implications in accurately predicting the field capacity of activated alumina under various local water quality conditions when multiple competitive anionic elements are present. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Activated Alumina, Adsorption, Arsenate, Arsenic, Arsenite, As(V), Competitive Adsorption, Drinking-Water, Equilibrium, Goethite, Kinetics, pH, Phosphate, Selenium, Selenium, Solutes, Speciation-Based Model, Surface, Vanadium, Water

? Zhou, Y., Yao, J., He, M.Y., Choi, M.M.F., Feng, L., Chen, H.L., Wang, F., Chen, K., Zhuang, R.S., Maskow, T., Wang, G.J. and Zaray, G. (2010), Reduction in toxicity of arsenic(III) to Halobacillus sp Y35 by kaolin and their related adsorption studies. Journal of Hazardous Materials, 176 (1-3), 487-494.

Full Text: 2010\J Haz Mat176, 487.pdf

Abstract: The growth of Halobacillus sp. Y35 has been investigated in HGM hypersaline medium with different doses of As(III) and kaolin. The metabolic heat flux decreases with the increase in As(III) concentration, indicating that strain Y35 lowers their metabolic activity in order to resist the As(III) toxicity. Carbon dioxide flux, cell growth and protein synthesis rates, and total thermal effect have been, for the first time, successfully employed simultaneously to assess the effect of As(III) on strain Y35 in the absence and presence of kaolin. The relative adsorption capacity and adsorption intensity of kaolin for As(III) are higher with strain Y35 than that without strain Y35, demonstrating that it is possible to reduce the toxicity of As(III) to our environment by both using mineral adsorption and biosorption technology. Our work shows the potential application of kaolin and strain Y35 for the removal of As(Ill) from contaminated groundwater. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Capacity, Arsenate, Arsenic, Bacillus-Halodurans, Biosorption, California, Carbon, Complexes, Groundwater, Halobacillus sp., Heavy-Metals, Kaolin, Microcalorimetry, Mixture Adsorbent, Reduction, Removal, Sediments, Sequence, Soil, Subtilis, Synthesis, Technology, Toxicity

? Al-Ghouti, M.A., Li, J., Salamh, Y., Al-Laqtah, N., Walker, G. and Ahmad, M.N.M. (2010), Adsorption mechanisms of removing heavy metals and dyes from aqueous solution using date pits solid adsorbent. Journal of Hazardous Materials, 176 (1-3), 510-520.

Full Text: 2010\J Haz Mat176, 510.pdf

Abstract: A potential usefulness of raw date pits as an inexpensive solid adsorbent for methylene blue (MB), copper ion (Cu2+), and cadmium ion (Cd2+) has been demonstrated in this work. This work was conducted to provide fundamental information from the study of equilibrium adsorption isotherms and to investigate the adsorption mechanisms in the adsorption of MB, Cu2+, and Cd2+ onto raw date pits. The fit of two models, namely Langmuir and Freundlich models, to experimental data obtained from the adsorption isotherms was checked. The adsorption capacities of the raw date pits towards MB and both Cu2+ and Cd2+ ions obtained from Langmuir and Freundlich models were found to be 277.8, 35.9, and 39.5 mg g(-1), respectively. Surface functional groups on the raw date pits surface substantially influence the adsorption characteristics of MB, Cu2+, and Cd2+ onto the raw date pits. The Fourier transform infrared spectroscopy (FTIR) studies show clear differences in both absorbances and shapes of the bands and in their locations before and after solute adsorption. Two mechanisms were observed for MB adsorption, hydrogen bonding and electrostatic attraction, while other mechanisms were observed for Cu2+ and Cd2+. For Cu2+, binding two cellulose/lignin units together is the predominant mechanism. For Cd2+. the predominant mechanism is by binding itself using two hydroxyl groups in the cellulose/lignin unit. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Activated Carbons, Adsorption, Adsorption Isotherms, Adsorption Mechanisms, Basic-Dyes, Cadmium, Copper, Date Pits, Dyes, Equilibrium, Fourier Transform Infrared, Freundlich, FTIR, Heavy Metals, Infrared, Ion Adsorption, Isotherms, Langmuir, Metal Ions (Cu²⁺ And Cd²⁺), Methylene Blue, Pore Structure, Sorption, Surface, Waste-Water

? Yang, J.Y., Yang, J., Zhou, Y., Lin, W.G., Wang, H.J. and Zhu, J.H. (2010), Effective nitrosamines trap derived from the in situ carbonized mesoporous silica MCM-41. Journal of Hazardous Materials, 176 (1-3), 602-608.

Full Text: 2010\J Haz Mat176, 602.pdf

Abstract: A new route to modify the mesoporous silica MCM-41 with carbon, using the inherent surfactant template in the as-synthesized sample as the carbon precursor, is reported in this article. Apart from the advantage of omitting energy and time required for removal of template, the resulting silica-carbon composites exhibit a high efficiency in adsorption and catalytic decomposition of N-nitrosopyrrolidine (NPYR), the typical carcinogenic pollutant in environment. The influence of carbonization temperature on the structure and performance of the resulting carbon-silica composite was investigated by use of XRD, N-2 adsorption-desorption, FTIR and TG-DSC techniques, and the instantaneous adsorption and the temperature-programmed surface reaction (TPSR) of NPYR as well as the reduction of nitrosamines level of cigarette smoke were also utilized to assess the actual function of these composites. The carbonization performed in the range of 773-973 K enabled the resulting composites to possess a higher activity than parent MCM-41 in eliminating volatile nitrosamines, which is beneficial for controlling carcinogenic pollutants in environment. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption, Composite, Environment Protection, FTIR, Functionalization, In Situ Carbonization, MCM-41, Mesoporous, Mesoporous Silica MCM-41, Molecular-Sieves, Nanocomposites, Nitrosamines, Removal, Silica, Smoke, Template Micelles, Volatile Nitrosamines, XRD, Zeolites

? Jiang, X. and Tay, J.H. (2010), Operational characteristics of efficient co-removal of H₂S and NH₃ in a horizontal biotrickling filter using exhausted carbon. Journal of Hazardous Materials, 176 (1-3), 638-643.

Full Text: 2010\J Haz Mat176, 638.pdf

Abstract: Odorous H2S and NH3 gases were effectively biodegraded in a horizontal biotrickling filter (HBTF) packed with H2S-exhausted carbon. During the process, the operational characteristics including the distribution of degradation products, biomass accumulation and biological activity, carbon surface characteristics and pressure drop were investigated. The results show that the content of biodegradation products on carbon was low, i.e. 0.9-2.8wt% S and 0.3-1.0wt% N. The low content benefited the stable operation of the HBTF, due to preventing a toxic concentration of degradation products on packing bed over a long-term operation. The biomass was distributed evenly along the HBTF. This avoided the problems of bed clogging and activity loss. On the other hand, the deteriorated performance was observed due to the biomass accumulation over a long-term operation. Carbon surface characteristics in the HBTF remained almost unchanged. pH values of carbon were neutral and micropore structure of carbon remained relatively stable. In addition, the pressure drop in the HBTF was very low. These operational characteristics of the HBTF system significantly contributed to efficient co-removal of H2S and NH3 in the HBTF over a long-term operation. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Ammonia, Biodegradation, Biodegradation Products, Biofilter, Biofiltration, Biological Activated Carbon, Biomass, Biomass Accumulation, Biomass Accumulation, Biotrickling Filter, Carbon, Degradation, Exhausted Carbon, Horizontal Biotrickling Filter, Hydrogen-Sulfide, Kinetics, Operational Characteristics, Performance, pH, Pressure, System

? Zheng, L.C., Dang, Z., Yi, X.Y. and Zhang, H. (2010), Equilibrium and kinetic studies of adsorption of Cd(II) from aqueous solution using modified corn stalk. Journal of Hazardous Materials, 176 (1-3), 650-656.

Full Text: 2010\J Haz Mat176, 650.pdf

Abstract: This paper describes the adsorption of cadmium ions from aqueous solution using acrylonitrile (AN)-modified corn stalk (AMCS). AMCS was characterized by elemental analysis, scanning electron microscopy, surface area and porosity analyzer, Fourier transform infrared and solid-state CP/MAS C-13 NMR spectra, and then used to evaluate the adsorption capacity in different pH values, adsorption isotherm, kinetics and thermodynamics in batch experiments. The results showed that AMCS is found to be an effective adsorbent because of its pore size and functional groups (-CN). The pH of 7.0 was an optimal pH for removal of Cd(II) ion and the Langmuir model provides a better fit to the equilibrium data than the Freundlich model, showing a maximum uptake of 12.73 mg g^-1, compared to raw corn stalk (RCS) (3.39 mg g^-1). Analysis indicated that pseudo-second-order kinetics controlled the adsorption rate. The activation energy (E,) was 9.43 kJ mol^-1. Thermodynamic parameters such as ΔG, ΔH and ΔS were also evaluated to predict the nature of adsorption process. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Acrylonitrile, Activated Carbon, Activation, Activation Energy, Adsorbent, Adsorption, Adsorption Capacity, Adsorption Isotherm, Adsorption Rate, Analysis, Aqueous Solution, Batch, Batch Experiments, C-13, Cadmium, Cadmium Ions, Capacity, Cd(II), Copper Ions, Corn, Corn Stalk, Data, Electrochemical Precipitation, Electron Microscopy, Energy, Equilibrium, Experiments, Freundlich, Freundlich Model, Functional Groups, Heavy-Metal Ions, Ions, Isotherm, Kinetic, Kinetic Studies, Kinetics, Kinetics and Thermodynamics, Langmuir, Langmuir Model, Lead Ions, Model, Modified, NMR, pH, Porosity, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-Second-Order, Pseudo-Second-Order Kinetics, Removal, Rice Husk, Rights, Scanning Electron Microscopy, Size, Solution, Sorption Isotherm, Sugarcane Bagasse, Surface, Surface Area, Thermal Characterization, Thermodynamic, Thermodynamic Parameters, Thermodynamics, Uptake, Waste-Water

? Wu, J., Zhang, H., He, P.J., Yao, Q. and Shao, L.M. (2010), Cr(VI) removal from aqueous solution by dried activated sludge biomass. Journal of Hazardous Materials, 176 (1-3), 697-703.

Full Text: 2010\J Haz Mat176, 697.pdf

Abstract: Batch experiments were conducted to remove Cr(VI) from aqueous solution using activated sludge biomass. The effects of acid pretreatment of the biomass, initial pH, biomass and Cr(VI) concentrations on Cr(VI) removal efficiency were investigated. Proton consumption during the removal process and the reducing capacity of sludge biomass were studied. The results show that acid pretreatment could significantly improve Cr(VI) removal efficiency and increase Cr(VI) reducing capacity by 20.4%. Cr(VI) removal was remarkably pH-dependent: lower pH (pH = 1, 2) facilitated Cr(VI) reduction while higher pH (pH = 3, 4) favored sorption of the converted Cr(III). Lower Cr(VI) concentration as well as higher biomass concentration could accelerate Cr(VI) removal. Cr(VI) reduction was not the only reason for proton consumption in the removal process. Pseudo-second-order adsorption kinetic model could successfully simulate Cr(VI) removal except under higher pH conditions (pH = 3, 4). (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Acid Pretreatment, Activated Sludge, Activated Sludge Biomass, Adsorption, Adsorption Kinetic, Agricultural Waste, Aqueous Solution, Biomass, Biosorbent, Biosorption, Capacity, Chromate, Concentration, Consumption, Cr(III), Cr(VI), Cr(VI) Reduction, Cr(VI) Removal, Dried Activated Sludge, Efficiency, Experiments, Hexavalent Chromium, Kinetic, Kinetic Model, Mechanism, Model, pH, pH-Dependent, Pretreatment, Pseudo-Second-Order, Reduction, Reduction, Removal, Removal Efficiency, Rights, Seaweed, Sludge, Sludge Biomass, Solution, Sorption, Water

? Yue, Q.Y., Zhao, Y.Q., Li, Q., Li, W.H., Gao, B.Y., Han, S.X., Qi, Y.F. and Yu, H. (2010), Research on the characteristics of red mud granular adsorbents (RMGA) for phosphate removal. Journal of Hazardous Materials, 176 (1-3), 741-748.

Full Text: 2010\J Haz Mat176, 741.pdf

Abstract: Red mud (RIM), a waste tailing from alumina industry, was employed with bentonite and starch as the main raw materials for producing granular adsorbents in this study. The important parameters, which greatly affect the characteristics of red mud granular adsorbents (RMGA), such as the mass ratio of three raw materials, preheating time, preheating temperature, sintering time and sintering temperature (ST), were investigated. Adsorption capacities for various RMGA were described in terms of removal of phosphate from aqueous solution according to the adsorption experiments, in which certain operation parameters (like stirring speed. reaction time, adsorbent dosage, initial pH and initial phosphate concentration) at three different aquatic temperatures (AT) were applied. The results showed that the optimum ST, under which the largest adsorption capacity was achieved for RMGA with certain RM ratio, varied with different AT in adsorption process. Based on the further characterizations of RMGA, it was speculated that the performance above was caused by the competitive interactions of chemical adsorption and physical adsorption on RMGA, since the increase in ST could lead to qualitative diversification on the surface and quantitative decrease of effective components for adsorption simultaneously. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Capacity, Adsorption Removal, Aqueous-Solutions, Ceramic Industry, Granular Adsorbents, Lead, Mechanisms, Metals, pH, Phosphate Removal, Red Mud, Removal, Research, Sludge, Waste-Water

? Vinu, R., Akki, S.U. and Madras, G. (2010), Investigation of dye functional group on the photocatalytic degradation of dyes by nano-TiO₂. Journal of Hazardous Materials, 176 (1-3), 765-773.

Full Text: 2010\J Haz Mat176, 765.pdf

Abstract: The photocatalytic degradation of five anionic, eight cationic and three solvent dyes using combustion-synthesized nano-TiO2 (CSTiO2) and commercial Degussa P-25 TiO2 (DP-25) were evaluated to determine the effect of the functional group in the dye. The degradation of the dyes was quantified using the initial rate of decolorization and mineralization. The decolorization of the anionic dyes with CSTiO2 followed the order: indigo carmine > eosin Y > amido black 10B > alizarin cyanine green > orange G. The decolorization of the cationic dyes with DP-25 followed the order: malachite green > pyronin Y > rhodamine 6G > azure B > nile blue sulfate > auramine O approximate to acriflavine P approximate to safranin O. CSTiO2 showed higher rates of decolorization and mineralization for all the anionic dyes compared to DP-25, while DP-25 was better in terms of decolorization for most of the cationic dyes. The solvent dyes exhibited adsorption dependent decolorization. The order of decolorization and mineralization of the anionic and cationic dyes (a) with CS TiO2 and DP-25 was different and correlated with the surface properties of these catalysts (b) were rationalized with the molecular structure of the dye and the degradation pathway of the dye. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Anionic Dyes, Aqueous-Solution, Azo Dyes, Cationic Dyes, Cs, Decomposition, Degradation, Dye, Dye Structure, Dyes, Indigo Carmine, Methylene-Blue, Mineralization, Nano TiO₂, Photocatalysis, Size, Solvent Dyes, TiO₂, UV, Visible-Light, Water

? Kumar, A., Prasad, B. and Mishra, I.M. (2010), Isotherm and kinetics study for acrylic acid removal using powdered activated carbon. Journal of Hazardous Materials, 176 (1-3), 774-783.

Full Text: 2010\J Haz Mat176, 774.pdf

Abstract: The potential of powdered activated carbon (PAC) for the adsorption of acrylic acid (AA) from aqueous solution was studied at the initial concentration (C-0) in the range of 50-500 mg/l over the temperature range of 303-348 K. The equilibrium adsorption studies were carried out to evaluate the effect of adsorbent dosage and contact time, change in pH by adding adsorbents and the initial concentration. Langmuir, Freundlich and Redlich-Peterson (R-P) equilibrium isotherm models were tested to represent the data. Error functions were used to test their validity to fit of the adsorption data with the isotherm and kinetic models. The Freundlich isotherm equation is found to best represent the equilibrium separation data in the temperature range of 303-348 K. The maximum adsorption capacity of AA onto PAC was obtained as q(m) = 36.23 mg/g with an optimum PAC dosage w = 20 g/l at 303 K for C-0 = 100 mg/l. The pseudo-second-order kinetics is found to represent the experimental AA-PAC data. The negative value of ΔG(ad)(0) (-16.60 to -18.18 kJ/mol K) indicate the feasibility and spontaneity of the adsorption process. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Acrylic Acid, Acrylonitrile, Activated Carbon, Adsorbent, Adsorbent Dosage, Adsorbents, Adsorption, Adsorption Capacity, Adsorption Characteristics, Adsorption Kinetics, Alumina, Aqueous Solution, Aqueous-Solution, Bagasse Fly-Ash, Capacity, Carbon, Catalysts, Concentration, Data, Equilibrium, Equilibrium Adsorption, Equilibrium Isotherm, Experimental, Feasibility, Freundlich, Freundlich Isotherm, Functions, Isotherm, Isotherms, Kinetic, Kinetic Models, Kinetics, Langmuir, Maleic-Acid, Models, PAC, pH, Poly(Acrylic Acid), Poly(Vinyl Pyrrolidone), Potential, Powdered Activated Carbon, Pseudo Second Order, Pseudo Second Order Kinetics, Pseudo-Second-Order, Pseudo-Second-Order Kinetics, Range, Redlich-Peterson, Removal, Rights, Separation, Solution, Temperature, Thermodynamics, Time, Validity, Value

? Madrid, F. and Florido, M.C. (2010), Effects of the presence of a composted biosolid on the metal immobilizing action of an urban soil. Journal of Hazardous Materials, 176 (1-3), 792-798.

Full Text: 2010\J Haz Mat176, 792.pdf

Abstract: The influence of a composted biosolid from urban wastewater treatment on the retention and solubility of Cu, Pb or Zn added to a soil was studied by batch adsorption/desorption experiments, equilibrating both materials and their mixtures with solutions containing various metal concentrations. The composted biosolid adsorbed less Cu or Pb and slightly more Zn than the soil, and thus caused a noticeable decrease in the retention of Cu or Pb and an increase in Zn adsorption by soil-biosolid mixtures, but these effects in the mixtures were not additive for any metal. The pH effects were studied by means of (log metal concentration)/pH diagrams. It was shown that Cu behaviour was different from that of the other metals: the relation between pH and Cu concentrations suggested similar solubilities in the presence of the biosolid and the mixtures, whereas the biosolid-free soil gave data located on a region of the diagram corresponding to slightly lower solubility. In the case of Pb or Zn, the data for the biosolid were located in a region of the diagram corresponding to clearly lower solubilities than those for the biosolid/soil mixtures. It was concluded that the biosolid has little effect on metal solubility when it is mixed with the soil in the proportions used here. (C) 2009 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Availability, Batch, Composted Biosolid, Contaminated Soil, Copper, Copper, Heavy-Metals, Lead, Lead, Ni, Pb, pH, Retention, Soil, Soil Metal Adsorption, Sorption, Treatment, Waste, Wastewater, Wastewater Treatment, Zinc, Zn

? Salman, J.M. and Hameed, B.H. (2010), Removal of insecticide carbofuran from aqueous solutions by banana stalks activated carbon. Journal of Hazardous Materials,