Influence of gasoline hydrocarbons on methyl tert-butyl ether biotreatment in fluidized bed bioreactors

Fluidized bed bioreactors (FBRs) are frequently used for the treatment of gasoline contaminated groundwater. Due to changes in gasoline formulations in the last decade, gasoline contaminated groundwater may also contain significant quantities of methyl tert-butyl ether (MTBE), a recalcitrant gasoline additive. It has been shown that MTBE is biodegradable and there is interest in determining if MTBE contaminated groundwater can be biologically treated using FBR technology. We examined the biodegradation of MTBE in FBRs treating contaminated groundwater and establish that there was an inverse correlation between total petroleum hydrocarbon (TPH) loading and MTBE treatment efficiency. Follow-up laboratory studies demonstrated that toluene, a component of TPH, is a strong inhibitor of MTBE biotreatment in FBRs.