Wetsus, Centre of Excellence for Sustainable Water Technology, Leeuwarden, The Netherlands.
Biotechnol Bioeng. 2012 Mar;109(3):657-64. doi: 10.1002/bit.24338. Epub 2011 Oct 28.
H(2) can be produced from organic matter with a microbial electrolysis cell (MEC). To decrease MEC capital costs, a cathode is needed that is made of low-cost material and produces H(2) at high rate. A microbial biocathode is a low-cost candidate, but suffers from a long startup and a low H(2) production rate. In this study, the effects of cathode potential and carbon source on microbial biocathode startup were investigated. Application of a more negative cathode potential did not decrease the startup time of the biocathode. If acetate instead of bicarbonate was used as carbon source, the biocathode started up more than two times faster. The faster startup was likely caused by a higher biomass yield for acetate than for bicarbonate, which was supported by thermodynamic calculations. To increase the H(2) production rate, a flow through biocathode fed with acetate was investigated. This biocathode produced 2.2 m(3) H(2) m(-3) reactor day(-1) at a cathode potential of -0.7 V versus NHE, which was seven times that of a parallel flow biocathode of a previous study.
H（2）可以通过微生物电解池（MEC）从有机物中产生。为了降低 MEC 的资本成本，需要一种由低成本材料制成的阴极，并且能够以高速率产生 H（2）。微生物生物阴极是一种低成本的候选物，但存在启动时间长和 H（2）产生速率低的问题。在这项研究中，考察了阴极电位和碳源对微生物生物阴极启动的影响。施加更负的阴极电位并没有降低生物阴极的启动时间。如果将乙酸盐而不是碳酸氢盐用作碳源，生物阴极的启动速度会快两倍以上。更快的启动可能是由于乙酸盐的生物量产率高于碳酸氢盐，这得到了热力学计算的支持。为了提高 H（2）的产生速率，考察了用乙酸盐为流动的生物阴极供电。这种生物阴极在-0.7 V 对 NHE 的阴极电位下产生了 2.2 m(3) H(2) m(-3) 反应器天(-1)，是之前研究的平行流动生物阴极的七倍。
