Development of a Bio-Electro-Process for in-situ remediation of chloroethene contaminated sites
Microbial degradation of volatile chlorinated hydrocarbons has been demonstrated repeatedly during the last years. Reductive dechlorination of chloroethenes (Halo-respiration) is possible in the presence of electron donors such as hydrogen. Oxidative dechlorination of the lower chlorinated metabolites (e.g. dichloroethene, vinyl chloride) can occur under aerobic conditions. However, under in-situ conditions the remediation efficacy often is limited by the lack of suitable electron donors and acceptors. The purpose of this project is to stimulate microbial chloroethene degradation by electrolytic processes.
Electrodes will be used to produce hydrogen and oxygen by water electrolysis. Hence, in the aquifer a sequential reductive and oxidative degradation of chlorothenes is possible. Within the project the optimal conditions for microbial chloroethene degradation as well as different electrode materials and geometries for electrolysis are examined. Chloroethene degradation, hydrogen and oxygen production will be studied in synthetic media with varying mineral composition and in groundwater. Furthermore, the effect of electric fields on the involved microorganisms and possible side reactions will be evaluated.
Preliminary studies confirmed the stimulating effect of electrolytically generated hydrogen and suggest that the combined Bio-Electro-process is a promising concept for in-situ-bioremediation.
