Acid mine drainage treatment and sequential metal recovery by means of bioelectrochemical technology

BACKGROUND This work studied the treatment of and metal recovery from a synthetic acid mine drainage (AMD) containing 500 mg L−1 copper (Cu2+) iron (Fe+3), 50 nickel (Ni2+) tin (Sn2+) by using bioelectrochemical system (BES). The presence electroactive bacteria improved performance such reactor configuration, contrast with systems abiotic anodes. RESULTS Operating as microbial fuel cell (MFC), all Fe3+ was reduced to Fe2+ in about 24 h Cu2+ electrodeposited onto cathodic surface, Cu electrode, obtaining pure Cu0. Almost catholyte recovered after four days. maximum current density power attained this stage were 0.136 mA cm−2 0.0134 mW cm−2, respectively. Subsequent operation electrolysis (MEC) allowed simultaneous Fe2+, Ni2+ Sn2+ fixing cathode potential at −0.7 V versus Ag/AgCl. electrode material titanium. completely deposited surface one day electrolysis. After three days, 77% 60% Ni Fe, respectively, recovered. CONCLUSION It possible recover Cu0 while generating electricity same time BES. voltage required for electrodeposition low case BES because contribution bacteria. Sequential deposition is adjusting operating parameters reactors. © 2021 Society Chemical Industry