Removal of MTBE from LEUNA groundwater by biological filtration

The groundwater at the LEUNA chemical company, Germany, has been contaminated by MTBE due to former production facilities. The project is part of a research consortium that focuses on various technologies to remove MTBE in-situ in horizontal filters/treatment units. In this project, the removal of MTBE by biological filtration was studied. MTBE is removed as a primary substrate with bacteria enriched from the local groundwater. The experiments were conducted with artificial LEUNA groundwater using a filtration unit with Filtralite (expanded clay)as the support material. MTBE and ammonia were effectively oxidized using either pure oxygen or hydrogen peroxide as oxidation agents. The MTBE degraders are growing very slowly, even more slowly than the nitrifyers. Under optimal conditions (20 dg. C), the doubing time for MTBE degraders was 7.5 days.