Transformation of tertiary butyl mercaptan in aerobic environments

Tertiary butyl mercaptan (TBM) is a malodorant that is added to natural gas in small quantities to aid in its detection. The objective of this study was to investigate the degradation of TBM under aerobic conditions. A bacterial culture was found that grew well on TBM in liquid minimal media under aerobic conditions. The doubling time was about 98 h at 30° C. In cultures where iron fillings were added, the growth rate increased and the doubling time was 44 h. In studies with manganese dioxide and potassium permanganate, TBM was oxidized chemically at rates that were rapid compared to those in the microbiological studies. Soil microcosms containing soil, water, and TBM were set up using two different soils and their headspace was sampled during a 62‐day period of study. In the first set, there was significantly greater reduction in TBM and production of carbon dioxide in the treatments compared to that of the sterilized controls. An intermediate product di‐tertiary‐butyl disulfide (DTBD) was identified. The experimental results show that TBM appears to be biodegradable in soil–water systems under aerobic conditions. © 2006 American Institute of Chemical Engineers Environ Prog, 2006