The removal of perchlorate from waters by a membrane-immobilized biofilm

This thesis investigated the feasibility of using a membrane-immobilized biofilm reactor to remove perchlorate from waters. Perchlorate (ClO4 -) is easily reduced under anaerobic conditions to harmless chloride (Cl-). In this system, the perchlorate-contaminated water is physically separated from the biofilm by the membrane. Perchlorate diffuses, without the need of external energy, to the degrading biofilm, thereby minimizing the contamination of the product water by microbes. A mixed microbial culture capable biologically of reducing perchlorate was enriched and attached to the membrane surface. The results demonstrated the feasibility of using a membrane-immobilized biofilm reactor to remove perchlorate from waters. In addition, the results showed that nitrate and salinity negatively affect perchlorate biodegradation, while sulfate does not have a major effect on perchlorate biodegradation