An MEC-MFC-coupled system for biohydrogen production from acetate.
Microbial fuel cells (MFCs) are devices that use bacteria as the catalysts to oxidize organic and inorganic matter and generate current whereas microbial electrolysis cells (MECs) are a reactor for biohydrogen production by combining MFC and electrolysis. In an MEC, an external voltage must be applied to overcome the thermodynamic barrier. Here we report an MEC-MFC-coupled system for biohydrogen production from acetate, in which hydrogen was produced in an MEC and the extra power was supplied by an MFC. In this coupled system, hydrogen was produced from acetate without external electric power supply. At 10 mM of phosphate buffer, the hydrogen production rate reached 2.2 +/- 0.2 mL L(-1) d(-1), the cathodic hydrogen recovery (RH2) and overall systemic Coulombic efficiency (CEsys) were 88 to approximately 96% and 28 to approximately 33%, respectively, and the overall systemic hydrogen yield (Y(sysH2)) peaked at 1.21 mol-H2 mol-acetate(-1). The hydrogen production was elevated by increasing the phosphate buffer concentration, and the highest hydrogen production rate of 14.9 +/- 0.4 mL L(-1) d(-1) and Y(sysH2) of 1.60 +/- 0.08 mol-H2 mol-acetate(-1) were achieved at 100 mM of phosphate buffer. The performance of the MEC and the MFC was influenced by each other. This MEC-MFC-coupled system has a potential for biohydrogen production from wastes, and provides an effective way for in situ utilization of the power generated from MFCs.
Sun
Min
M
Department of Chemistry and Materials Science, University of Science & Technology of China, Hefei, 230026 China.
Sheng
Guo-Ping
GP
Zhang
Lei
L
Xia
Chang-Rong
CR
Mu
Zhe-Xuan
ZX
Liu
Xian-Wei
XW
Wang
Hua-Lin
HL
Yu
Han-Qing
HQ
Qi
Rong
R
Yu
Tao
T
Yang
Min
M
D000085:Acetates / Q000378:metabolism*; D001419:Bacteria / Q000166:cytology* / Q000378:metabolism*; D001674:Bioelectric Energy Sources; D002021:Buffers; D004560:Electricity; D004572:Electrolysis; D006859:Hydrogen / Q000378:metabolism*; D012996:Solutions
D000085:Acetates; D002021:Buffers; D012996:Solutions; D006859:Hydrogen