초록
<P><B>Abstract</B></P> <P>Hydrogen production during dark fermentation is inhibited by the co-production of volatile fatty acids (VFAs) such as acetic and n-butyric acid. In this study, the effectiveness of conventional electrodialysis (CED) in reducing VFA concentrations in model solutions and hydrogen fermentation broths is evaluated. This is the first time CED has been reported to remove VFAs from hydrogen fermentation broths. During 60min of operation CED removed up to 99% of VFAs from model solutions, sucrose-fed and grass-fed hydrogen fermentation broths, containing up to 1200mgl<SUP>−1</SUP> each of acetic acid, propionic acid, i-butyric acid, n-butyric acid, i-valeric acid, and n-valeric acid. CED’s ability to remove VFAs from hydrogen fermentation broths suggests that this technology is capable of improving hydrogen yields from dark fermentation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Conventional electrodialysis used to remove VFAs from H<SUB>2</SUB> fermentation broths for the first time. </LI> <LI> VFA removal from fermentation broths was equal or greater than from model solutions. </LI> <LI> Up to 99% of VFA removal from fermentation broths was achieved within 60min. </LI> <LI> Removed VFAs are recoverable for use in bioenergy systems and as raw materials. </LI> </UL> </P>