The
efficiency and characteristics of conversion of volatile fatty
acids (VFAs) into alcohols by a microbial electrosynthesis (MES) process
were significantly influenced by the initial organic loading concentration
and operational period. The acetate and butyrate concentrations ranged
from 2 to 8 g-COD/L, and alcohol and other product formations were
determined over a 5 day operation. The highest yield of 0.218 g-CODAlcohol/g-CODVFAs was obtained for 4 g-COD/L after
a 1 day operation. A gradual decrease over time in alcohol recovery
was noticed for all VFA concentrations due to methane generation under
elevated pH conditions. At the end of the operation, a higher bioalcohol
yield was achieved at a relatively lower VFA concentration of 2 g-COD/L.
A large fraction of initial VFAs remained unchanged without bioenergy
production from higher substrate concentrations (6 and 8 g-COD/L).
The energy recovery of total products (alcohols and methane) based
on the input power was less than about 24% at the end of the operation.
This study suggests that the optimized loading of VFA and low-pH conditions
are essentially required to increase the overall performance of the
MES system for alcohol production.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.