Personal Research Database

Full Text: J\J Haz Mat60, 205.pdf

Abstract: The object of this article is to discuss the purification of a special thermal water of a geogene origin, containing potentially toxic, organic micropollutants like benzene, toluene, mesitylene, xylene and phenols. As the flotation of the thermal water on model laboratory equipment did not remove ah toxic organic substances present from water, A. granular activated carbon (GAC) filter column was used. Although the use of granular carbon adsorption is well known in potable water treatment, in industrial water polishing and waste water treatment, there is no information about its use for the purification of special thermal water. The result of the purification with GAC adsorption is thermal water with quality that corresponds to requirements of DIN 19643 for bathing water. After this treatment thermal water reached the hygienic quality of drinking water and could be used for balneological purposes. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Thermal Water, Organic Micropollutants, Benzene, Toluene, Xylene

Karlsson, E. and Nyholm, S. (1998), Dry deposition and desorption of toxic gases to and from snow surfaces. Journal of Hazardous Materials, 60 (3), 227-245.

Full Text: J\J Haz Mat60, 227.pdf

Abstract: A model describing toxic gas deposition to and desorption from a snow surface is presented. The model is based on the assumption that the deposition is caused by an adsorption of the toxic gas to small amounts of liquid water, which exist in the snow at temperatures equal to or below 0C. It includes molecular diffusion in the snow, partition between gas and solution by use of Henry’s law, drainage flow in melting snow and decomposition of agent. The interface to the atmosphere is defined by the flux to and from the surface with help of the aerodynamic resistance and the resistance in the viscous sub-layer. Deposition velocities to snow for some air pollutants are reviewed. The model is compared with sarin experiments in a test chamber, which verifies two main features of the model-primarily decreasing deposition with time and decreasing deposition with decreasing temperature. The model shows that the accumulation of sarin in the top layer of snow could be high enough to give lethal or severe injuries to people if the snow was used as drinking water. However, there is a tendency of the model to give too low deposition (too high surface resistance). Possible reasons for this observation are discussed. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Sulfur-Dioxide, Nitric-Acid, Model, SO₂, O₃, Ice, Deposition, Desorption, Snow, Toxic Gas, Nerve Agent, Sarin

Yang, G.C.C. and Yang, T.Y. (1998), Synthesis of zeolites from municipal incinerator fly ash. Journal of Hazardous Materials, 62 (1), 75-89.

Full Text: J\J Haz Mat62, 75.pdf

Abstract: In this work, synthesis of zeolite-like materials from a municipal incinerator fly ash (MIFA) was carried out by means of hydrothermal processing. MIFA is generally hazardous in nature. Therefore, many technologies have been developed for the treatment, disposal, and utilization of this special waste. In this investigation, conversion of MIFA to zeolite-like materials was conducted in reaction bombs that were subjected to heating in a rocking chamber. Aqueous NaOH was used as a mineralizer to assist the conversion reaction. Experimental parameters studied include the mineralizer concentration, solid/liquid (i.e., MIFA/mineralizer) ratio, reaction time, and operating temperature. Powder patterns of X-ray diffraction analysis have shown that several types of zeolite such as gismondine and gmelinite were successfully synthesized under certain experimental conditions. Therefore, it is technically feasible to synthesize zeolites from MIFA. Based on the promising results obtained, further studies are under way to upgrade the quality of synthesized products so that their applications could be expanded. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Municipal Incinerator Fly Ash, Synthesis, Zeolite, Physicochemical Properties

? Gotpagar, J.K., Grulke, E.A. and Bhattacharyya, D. (1998), Reductive dehalogenation of trichloroethylene: kinetic models and experimental verification. Journal of Hazardous Materials, 62 (3), 243-264.

Full Text: 1998\J Haz Mat62, 243.pdf

Abstract: This paper develops a generalized kinetic model for two-phase systems involving reactions in one phase with product partitioning into a second phase, and applies it to the reductive dehalogenation of trichloroethylene using two systems. The generalized approach can be used for a variety of catalyst choices, including zero-valent metals. With vitamin B-12, the model includes specific reaction pathways for the reductive dehalogenation of TCE combined with the partitioning of reactants, intermediates, and products between the gas and liquid phases. The model has been used to study the effect of various parameters on the process effectiveness, which otherwise are very difficult to conceive through experimental analysis. In the case of zero-headspace system with zero-valent iron, sorption effects are included to incorporate the partitioning onto the solid surface. A new parameter, ‘fractional active site concentration’ is introduced to incorporate the differences in reactive and nonreactive sites on the iron surface, which affects the degradation performance. The generalized model has important implications for kinetic modeling, monitoring of VOCs and their degradation products, and design and selection of remediation technologies for such materials. The model predictions have been verified with our experimental data and the results from the Literature. (C) 1998 Published by Elsevier Science B.V. All rights reserved.

Keywords: Analysis, Catalyst, Dechlorination, Degradation, Dehalogenation, Design, Effectiveness, Henrys Law Constants, Homogeneous Aqueous-Solution, Iron, Kinetic, Kinetic Model, Kinetic Modeling, Kinetic Models, Mediated Reduction, Metal, Metals, Model, Modeling, Models, Monitoring, Partitioning, Pathways, Performance, Process, Reductive Dehalogenation, Remediation, Remediation Technologies, Rights, Selection, Sorption, Surface, Systems, TCE, Tetrachloroethylene, Trichloroethylene, Vitamin B-12, VOCs, Zero Valent Iron, Zero-Valent Iron, Zerovalent Iron

? Westin, S.N., Winter, S., Karlsson, E., Hin, A. and Oeseburg, F. (1998), On modeling of the evaporation of chemical warfare agents on the ground. Journal of Hazardous Materials, 63 (1), 5-24.

Full Text: 1998\J Haz Mat63, 5.pdf

Abstract: A model for evaporation of chemical warfare agents on the ground has been developed. The process of evaporation is described in three steps: (1) the immediate drop enlargement due to impact momentum is modeled using an empirical correlation from technical literature; (2) further enlargement caused by capillary spreading upon the surface and the simultaneous sorption into the substrate, modeled in three dimensions; (3) subsequent drying and redistribution of the sorbed material is described as a one-dimensional (vertical) process, The formulation of the flux in the soil takes into account vapour, liquid, solute, and adsorbed phases. The evaporation from the surface is determined by the vapour concentration at the surface and the conditions in the atmospheric viscous sub-layer close to the droplet spots on the surface., Model results agree with the limited experimental data found in the literature. The model shows a very rapid sorption and redistribution of chemical warfare droplets on sand. This effect gives a rapid decrease of the evaporation, except for a shorter initial period. However, a small residual evaporation exists for a rather long time from liquid, which has penetrated down into the soil. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Behavior, Chemical Warfare, Correlation, Diffusivity, Droplet, Evaporation, Impact, Infiltration, Liquid, Literature, Model, Modeling, Porous-Media, Process, Redistribution, Rights, Sand, Simultaneous Sorption, Soil, Sorption, Surface, Transport, Vapor, Vapour Concentration

Lee, S.Z., Chang, L., Yang, H.H., Chen, C.M. and Liu, M.C. (1998), Adsorption characteristics of lead onto soils. Journal of Hazardous Materials, 63 (1), 37-49.

Full Text: J\J Haz Mat63, 37.pdf

Abstract: The metal adsorption characteristics of fifteen Taiwan soils, exemplified by Pb(II), were evaluated using pH as the major variable. The soil samples were thoroughly characterized for their physical chemical properties and composition, particularly organic matter and metal oxides. The adsorption of Pb(II) followed the Langmuir relation and increased with increasing pH between pH 3.0 and 8.5, The greater adsorption was found for soils with a higher organic matter content at constant pH and metal concentration. To better understand the mechanism of adsorption, the experimental results for Pb(II) were tested in a partition coefficient model to relate the adsorption of the Pb(II) by the different soils with soil components: organic matter, iron oxide, aluminum oxide and manganese oxide. This model was not successful when applied to measurements at the natural soil pH because of the competition of protons with lead for available sites. However, partition coefficients obtained from experimental data were highly correlated with those calculated for a partition coefficient between lead and organic matter alone. Normalization of the partition coefficients, K-d, for the organic matter content of the soils, K-om, greatly improved the correlation between the partition coefficient and pH (R-2 increased from 0.602 to 0.855), This suggests that the surficial adsorption sites are principally due to organic matter, For the 24-h equilibration period employed, diffusion of Pb through this superficial organic matter coating to underlying sorptive materials, including metal oxides, is not important in the partitioning of Pb. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Soil, Pb, Adsorption, Partition Coefficient, Organic Matter, Metal Oxides, Organic-Matter, Sorption

Sekaran, G., Shanmugasundaram, K.A. and Mariappan, M. (1998), Characterization and utilisation of buffing dust generated by the leather industry. Journal of Hazardous Materials, 63 (1), 53-68.

Full Text: J\J Haz Mat63, 53.pdf

Abstract: Buffing dust is a proteinous solid waste impregnated with chromium, synthetic fat, oil, tanning agents and dye chemicals which is generated during the manufacture of leather. About 2-6 kg of buffing dust is liberated as a solid waste per ton of skin/hide processed. The concentration of chromium in the dust is 27 g/kg of dust. Dumping of solid waste as landfill accounts for soil and groundwater contamination. The maximum concentration of the chromium in the contaminated soil and groundwater were 714 mg/kg of soil and 0.25 mg/l, respectively. A method to generate activated carbon from the buffing dust is discussed. The adsorption capacity of activated carbon obtained from buffing dust was 6.24 mg/g at pH 3.5, temperature 30C for dye concentration of 6.25 mg/l and activation temperature 800C. The rate constant for removal of dye was 0.026 min^-1. The effect of initial dye concentration, pH, temperature and particle size on adsorption of dye are also determined. (C) 1998 Published by Elsevier Science B.V. All rights reserved.

Keywords: Buffing Dust, Leather Industry, Leachates, Activated Carbon, Adsorption, Natural Adsorbents, Acid Dye, Fly-Ash, Removal, Chromium

? Ramirez, J.A. and Davis, R.H. (1998), Application of cross-flow microfiltration with rapid backpulsing to wastewater treatment. Journal of Hazardous Materials, 63 (2-3), 179-197.

Full Text: 1998\J Haz Mat63, 179.pdf

Abstract: Cross-flow microfiltration with rapid backpulsing was investigated for the removal of suspended solids and dispersed oil from an aqueous stream. Laboratory experiments performed on clay suspensions demonstrate that rapid backpulsing can maintain the permeate flux at a level which is more than 10-fold over the long-term flux in the absence of backpulsing, without any reduction in the permeate quality. Experiments with dilute oil-in-water dispersions show that rapid backpulsing can increase the permeate flux by up to 25 times; however, the enhanced performance in this case cannot be maintained over the life of the membrane and is highly dependent on the degree of membrane use. An economic analysis shows that cross-flow microfiltration without backpulsing is not economically feasible when compared to conventional treatment methods, but that operation with backpulsing at the enhanced permeate flux levels observed for the clay experiments will result in lower costs of treated water than for conventional methods, for facilities with capacities of up to 6000 m³ d^-1. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Adsorption, Analysis, Backpulsing, Clay, Costs, Cross Flow, Crossflow Microfiltration, Economic, Experiments, Filtration, Flux, Life, Membrane, Membranes, Methods, Microfiltration, Oil, Oily-Water, Performance, Permeate Flux, Quality, Reduction, Removal, Rights, Treatment, Wastewater, Wastewater Treatment, Water

Chan, C.C.Y. and Kirk, D.W. (1999), Behaviour of metals under the conditions of roasting MSW incinerator fly ash with chlorinating agents. Journal of Hazardous Materials, 64 (1), 75-89.

Full Text: J\J Haz Mat64, 75.pdf

Abstract: A total elemental analysis was performed on a municipal solid waste (MSW) fly ash sample, before and after it was treated at 1000C, to reveal the metal distribution between the volatile matter and the ash residue. Metals such as Pb, Zn, Cd, and to a lesser degree, Cr, Mn and Ni, were volatilized. Addition of chlorinating agents generally increased the volatility of certain elements. More acid resistant compounds were formed in the ash residue after the heat treatment using CaCl₂ as a chlorinating agent. The efficiencies of volatilization of the metals, using Cl₂ as a chlorinating agent, were generally higher compared with using CaCl₂. However, CaCl₂ was found to be a more selective chlorinating agent for volatilizing the heavy metals of concern, i.e., Pb, Cd, Zn and Cu. The efficiencies of volatilization of the recovered metals were approximately proportional to their standard free-energy changes G for the corresponding chlorination reactions. (C) 1999 Elsevier Science B.V. All rights reserved.

Keywords: Municipal Solid Waste (Msw) Fly Ash, Roasting, Chlorinating Agent, Heavy Metal, Volatilization Efficiency, Electrostatic Precipitator Ash, Heavy-Metals, Waste

? Aminabhavi, T.M. and Naik, H.G. (1999), Sorption/desorption, diffusion, permeation and swelling of high density polyethylene geomembrane in the presence of hazardous organic liquids. Journal of Hazardous Materials, 64 (3), 251-262.

Full Text: 1999\J Haz Mat64, 251.pdf

Abstract: The laboratory findings on sorption and desorption of 14 organic Liquids into high density polyethylene (HDPE) geomembranes are presented at 25, 50 and 70 C. The values of diffusion and permeation coefficients have been calculated using these data. Swelling of the HDPE geomembrane was studied by monitoring its increase in thickness and diameter and thereby calculating the increase in volume. From a temperature dependence of sorption, diffusion and permeation coefficients, the Arrhenius parameters have been calculated. From the sorption data, the concentration profiles of Liquids inside the HDPE by solving Fick’s diffusion equation under the appropriate initial and boundary conditions. Results of this research may have relevance in the application of HDPE geomembrane in the hazardous waste environment containing the solvents used in this research. (C) 1999 Elsevier Science B.V. All rights reserved.

Keywords: Aliphatic Esters, Copolymer, Dependence, Desorption, Diffusion, Environment, Geomembrane, Hazardous Waste, HDPE Geomembrane, Membranes, Monitoring, Permeation, Presence, Relevance, Research, Rights, Sorption, Sorption, Swelling, Temperature, Transport, Values

? Raihala, T.S., Wang, Y. and Jackman, A.P. (1999), Slow desorption of volatile organic compounds from soil: evidence of desorption step limitations. Journal of Hazardous Materials, 65 (3), 247-265.

Full Text: 1999\J Haz Mat65, 247.pdf

Abstract: Transient adsorption and desorption of 1,2 dichloroethane and toluene on dry Yolo silt loam soil were studied by continuously measuring the composition of the effluent from a soil-packed chromatography column with a mass spectrometer. After obtaining complete breakthrough at approximately 30% relative saturation of one chemical in nitrogen, pure nitrogen feed was initiated and maintained for several hours. Of the material adsorbed at breakthrough, 9.7% of the 1,2 dichloroethane and 14.2% of the toluene were highly resistant to desorption and remained sorbed on the soil even after 5 h of nitrogen flow. When a second chemical with a higher adsorption affinity was introduced into the soil column (water following toluene or toluene following 1,2 dichloroethane), the majority of the first chemical was quickly desorbed and began leaving the soil column before breakthrough of the second chemical. Conversely, when a second chemical with a smaller adsorption affinity was introduced into the soil column, only a small amount of the first chemical was displaced and began leaving the soil column after breakthrough of the second chemical. The results of this study indicate that the desorption step itself may be the rate-limiting step for sorbate which remains after prolonged exposure to sorbate-free gas. (C) 1999 Elsevier Science B.V. All rights reserved.

Keywords: Adsorption, Adsorption, Breakthrough, Column, Composition, Desorption, Effluent, Evidence, Exposure, Limitations, Minerals, Nitrogen, Organic Compounds, Particles, Prolonged Exposure, Rate-Limiting Step, Retention, Rights, Slow Desorption, Soil, Soil Column, Sorbate, Sorption, Sorption Kinetics, Toluene, Volatile Organic Compounds, Water

? Peters, R.W. (1999), Chelant extraction of heavy metals from contaminated soils. Journal of Hazardous Materials, 66 (1-2), 151-210.

Keywords: Acetate, Achieved, Acid, Adsorption-Desorption Characteristics, Ammonium, Art, Batch, Carbonate, Cd, Chelant Extraction, Chelating Agents, Chelating Extraction, Citric Acid, Clay, Contaminants, Contaminated Soil, Copper, Copper, Cu, Current, Distribution, EDTA, Extraction, Heavy Metal, Heavy Metals, Heavy-Metal, Leaching, Lead, Lead, Metal, Metals, N-(2-Acetamido)Iminodiacetic Acid, Operating Conditions, Oxalate, Oxides, Particle Size, Pb, Pb-Polluted Soils, Phosphoric Acid, Pyridine-2,6-Dicarboxylic Acid, Remediation, Removal, Rights, Sand, Soil, Soil Flushing, Soil Washing, Soils, Speciation, State, TCLP, Technique, Toxicity, Washing, Water, Zinc, Zn

? Smyth, T.J., Zytner, R.G. and Stiver, W.H. (1999), Influence of water on the supercritical fluid extraction of naphthalene from soil. Journal of Hazardous Materials, 67 (2), 183-196.

Full Text: 1999\J Haz Mat67, 183.pdf

Abstract: Supercritical fluid extraction (SFE) is an innovative soil remediation technology. To aid system evaluation and design, thermodynamic and kinetic parameters have been measured using a naphthalene contaminated, loamy sand at various water contents. The experimental results show that supercritical carbon dioxide can easily extract naphthalene from soil when the water content is below 10%. At low water contents, mass transfer is rapid and the equilibrium partition coefficient is independent of the soil’s water content. However, the overall mass transfer coefficient, (k(ov) a), decreases by at least a factor of 200 as the water content increases from 10 to 20%. (C) 1999 Elsevier Science B.V. All rights reserved.

Keywords: Carbon, Carbon-Dioxide Extraction, Design, Equilibrium, Evaluation, Extraction, Kinetic, Kinetic Parameters, Mass Transfer, Mass Transfer Coefficient, Matrices, Naphthalene, Organics, Organics, Partition, Partition Coefficient, Pollutants, Remediation, Rights, Sand, Soil, Soil Remediation, Sorption, Supercritical Carbon Dioxide, Supercritical Fluid, Technology, Thermodynamic, Transfer, Water

? Cabbar, H.C. (1999), Effects of humidity and soil organic matter on the sorption of chlorinated methanes in synthetic humic-clay complexes. Journal of Hazardous Materials, 68 (3), 217-226.

Full Text: 1999\J Haz Mat68, 217.pdf

Abstract: Vapor-phase sorption is the most influential process governing the transport and the fate of volatile organic compounds in soil. To understand the influence of both soil organic content and the humidity of soil on the vapor sorption is an important process for degradation processes. The single-pellet moment technique was used to investigate sorption and diffusion of trichloromethane (TCM) and carbon tetrachloride (CTC) at varying relative humidities (0-80%) of synthetic humic-clay complex pellets consisting of clay (montmorillonite) and different amounts of organic matter (humic acid). The effective diffusivities of TCM and CTC did not show a noticeable change with moisture and humic acid content. On the other band, with increasing humic acid content of clay at 0% relative humidity, an appreciable decrease of the equilibrium sorption constants of the tracers (TCM, CTC) was found because of the blockage of some sites of the mineral surfaces and especially micropores by the humic acid. The presence of water also reduced dramatically the sorption of TCM and CTC on synthetic humic-clay complexes. Above 20% relative humidity, the sorption coefficient of TCM and CTC varied only slightly with humic acid content. It was concluded that the sorption of TCM and CTC in synthetic humic-clay complexes was strongly effected by the moisture and humic acid content. (C) 1999 Elsevier Science B.V. All rights reserved.

Keywords: Acid, Adsorption In Soil, Carbon, Change, Clay, Degradation, Diffusion, Diffusion In Soil, Equilibrium, Gas-Phase, Humic Acid, Humidity, Influence, Minerals, Moist Soil, Moisture, Moment Technique, Montmorillonite, Organic Compounds, Organic Content of Soil, Organic Matter, Presence, Process, Rights, Single-Pellet Technique, Soil, Soil Organic Matter, Sorption, Technique, Temperature, Transport, Vapor-Phase Sorption, VOCs, Volatile Organic Compounds, Water

Tsai, W.T., Chang, C.Y., Ho, C.Y. and Chen, L.Y. (1999), Adsorption properties and breakthrough model of 1,1-dichloro-1-fluoroethane on activated carbons. Journal of Hazardous Materials,