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Title: Gypsum bioconversion to sulfur: a two-step microbiological process

Conference · · Dev. Ind. Microbiol.; (United States)
OSTI ID:6332993

The isolation, cultivation, and process applications of a sulfate-reducing bacterial strain are described. The organism is an obligate anaerobe, gram-negative species capable of propagation in an inorganic medium with acetate as the sole preformed carbon source; gaseous products of metabolism are hydrogen sulfide and carbon dioxide. The strain is here referred to as a Desulfobacter sp. In the context of gypsum control and removal, this organism appears suitable for the first step of a two-step bioconversion process wherein sulfate ultimately is converted to elemental sulfur. The second organism is Chlorobium limicola f. sp. thiosulfatophilum, a photosynthetic green sulfur bacterium which converts the hydrogen sulfide and carbon dioxide produced by Desulfobacter to free sulfur, biomass, and soluble organic acids which are suitable metabolites for the support of growth of Desulfobacter. Preliminary data are presented for the rate of sulfate reduction, which can reach levels of 1.58 mmol liter hr when cultures are operated in a chemostat mode. Initial results suggest that batch cultures of Chlorobium will continue conversion of H2S to S after cell division has ceased. Net free sulfur production was reduced by the appearance of increasing levels of thiosulfate and sulfate, possibly because of altered metabolic pathways during senescence of the culture or because of nutritional limitations. 14 references, 3 figures.

Research Organization:
Illinois Institute of Technology, Chicago
OSTI ID:
6332993
Report Number(s):
CONF-8208164-
Journal Information:
Dev. Ind. Microbiol.; (United States), Vol. 24; Conference: 39. general meeting of the Society for Industrial Microbiology, St. Paul, MN, USA, 14 Aug 1982
Country of Publication:
United States
Language:
English