Microbial electrolysis cell: Hydrogen production using microbial consortia from Romanian waters

The present study aims to provide additional insight into the bioelectrochemical processes that drive biohydrogen production by microorganisms living in aqueous ecosystems. To this end, we have obtained water samples from three locations in Romania (the Black Sea, Lake Siutghiol and the River Sabar), and employed them in the cathodic chamber of a Microbial Electrolysis Cell (MEC) run at a negative polarization of 1,100mV vs. Ag|AgCl. The microbial species present in the water samples employed in the MEC proved capable of driving biohydrogen production through electrolysis without the need of mediators, reaching a maximum efficiency of 57% in biohydrogen production using the marine waters sample. Microbial activity also led to the reduction of nitrates present in the wastewater substrate; this may spell promising developments in wastewater treatment coupled with biohydrogen production.