Controlling Ethanol Use in Chain Elongation by CO2 Loading Rate.

ABSTRACT: Chain elongation is an open-culture biotechnological process which converts volatile fatty acids (VFAs) into medium chain fatty acids (MCFAs) using ethanol and other reduced substrates. The objective of this study was to investigate the quantitative effect of CO2 loading rate on ethanol usages in a chain elongation process. We supplied different rates of CO2 to a continuously stirred anaerobic reactor, fed with ethanol and propionate. Ethanol was used to upgrade ethanol itself into caproate and to upgrade the supplied VFA (propionate) into heptanoate. A high CO2 loading rate (2.5 LCO2·L-1·d-1) stimulated excessive ethanol oxidation (EEO; up to 29%) which resulted in a high caproate production (10.8 g·L-1·d-1). A low CO2 loading rate (0.5 LCO2·L-1·d-1) reduced EEO (16%) and caproate product

SUBMITTER: Roghair M 

PROVIDER: S-EPMC5997387 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature