Removal of Hg2+ as an electron acceptor coupled with power generation using a microbial fuel cell.

In this study, removal of Hg(2+) as an electron acceptor of a microbial fuel cell (MFC) was successfully achieved. The initial pH affected the removal efficiency of Hg(2+) from electrochemical and chemical reactions. The effluent Hg concentrations for initial Hg(2+) concentration of 50mg/L after a 5-h reaction were 3.08 ± 0.07, 4.21 ± 0.34, 4.84 ± 0.00, and 5.25 ± 0.36 mg/L for initial pH of 2, 3, 4, and 4.8, respectively. For 10-h reaction, the effluent Hg concentration was in the range of 0.44-0.69 mg/L, for different initial Hg(2+) concentrations (25, 50, and 100mg/L). Lower initial pH and higher Hg(2+) concentration resulted in larger maximum power density. A maximum power density of 433.1 mW/m(2) was achieved from 100mg/L Hg(2+) at pH 2.