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Kinetics of the Removal of Iron Pyrite from Coal by Microbial Catalysis

Hoffmann, Michael R. and Faust, Bruce C. and Panda, Fern A. and Koo, Hong H. and Tsuchiya, Henry M. (1981) Kinetics of the Removal of Iron Pyrite from Coal by Microbial Catalysis. Applied and Environmental Microbiology, 42 (2). pp. 259-271. ISSN 0099-2240. PMCID PMC244000.

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Different strains of Thiobacillus ferrooxidans and Thiobacillus thiooxidans were used to catalyze the oxidative dissolution of iron pyrite, FeS2, in nine different coal samples. Kinetic variables and parametric factors that were determined to have a pronounced effect on the rate and extent of oxidative dissolution at a fixed Po2 were: the bacterial strain, the nitrogen/phosphorus molar ratio, the partial pressure of CO2, the coal source, and the total reactive surface area of FeS2. The overall rate of leaching, which exhibited a first-order dependence on the total surface area of FeS2, was analyzed mathematically in terms of the sum of a biochemical rate, {nu}1, and a chemical rate, {nu}2. Results of this study show that bacterial desulfurization (90 to 98%) of coal samples which are relatively high in pyritic sulfur can be achieved within a time-frame of 8 to 12 days when pulp densities are ≤20% and particle sizes are ≤74 µm. The most effective strains of T. ferrooxidans were those that were isolated from natural systems, and T. ferrooxidans ATCC 19859 was the most effective pure strain. The most effective nutrient media contained relatively low phosphate concentrations, with an optimal N/P molar ratio of 90:1. These results suggest that minimal nutrient additions may be required for a commercial desulfurization process.

Item Type:Article
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Hoffmann, Michael R.0000-0001-6495-1946
Additional Information:Copyright © 1981 by the American Society for Microbiology. Received 29 December 1980/Accepted 26 May 1981. Support for this research was provided by the U.S. Department of Energy (grant EF-77-G-01-2747 and contract no. ET-78-01-3289). This support was greatly appreciated. In addition, we are grateful to O.M. Tuovinen, J.M. Falch, and B.C. Lim for their valuable contributions.
Funding AgencyGrant Number
Department of Energy (DOE)EF-77-G-01-2747
Department of Energy (DOE)ET-78-01-3289
Issue or Number:2
PubMed Central ID:PMC244000
Record Number:CaltechAUTHORS:HOFaem81
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:12287
Deposited By: Archive Administrator
Deposited On:04 Nov 2008 00:29
Last Modified:03 Mar 2020 13:01

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