Bioelectrochemical Ethanol Production through Mediated Acetate Reduction by Mixed Cultures

摘要: Biological acetate reduction with hydrogen is a potential method to convert wet biomass waste into ethanol. Since the ethanol concentration and reaction rates are low, this research studies feasibility of using an electrode, in stead hydrogen, as electron donor for biological conjunction mediator. Initially, effect three selected mediators on metabolic flows during was explored; subsequently, best performing mediator used bioelectrochemical system stimulate at cathode mixed cultures applied -550 mV. In batch test, methyl viologen (MV) found accelerate production 6-fold increased 2-fold 13.5 +/- 0.7 mM compared control. Additionally, MV inhibited n-butyrate methane formation, resulting high efficiency (74.6 6%). system, addition inoculated led directly (1.82 mM). Hydrogen coproduced (0.0035 Nm(3) m(-2) d(-1)), so it remained unclear whether reduced by electrons supplied or hydrogen. As reacted irreversibly cathode, stopped after 5 days.