DECOMPOSITION OF SOME ORGANIC SULFUR COMPOUNDS IN PETROLEUM BY ANAEROBIC BACTERIA

Abstract

Four kinds of bacterial cultures, which produce H2S from organic sulfur compounds such as thiophene, dimethyl sulfide, 1-butanethiol, polysulfides, as well as from crude oil, residue oil, and asphaltene, were isolated from sludges collected from oil well or reservoir bottom of crude oil. The culture which decomposes thiophene contained bacterial cells which are gram-negative and of rod shape with average dimension of 3×0.5μ. The bacteria grow optimally at pH 7.2-7.8 and at 38° in N2 or H2. Polypeptone is essential for their growth, and addition of FePO4 increases the rate of H2S production. The cell-free extract of thiophene-decomposing bacteria catalyzes the production of H2S from thiophene in the presence of methyl viologen in H2.