Zero-valent Iron Enhances Acetate and Butyrate Production from Carbon Monoxide by Fonticella tunisiensis HN43

Journal article, 2023

The use of carbon monoxide (CO) as a valuable feedstock for producing various platform chemicals through biorefinery processes has attracted considerable research interest. Acetate is an intermediate chemical synthesized from CO and CO2 through acetogenesis via the Wood–Ljungdahl pathway. Acetate can further serve as a substrate for chain elongation into a higher volatile fatty acid (VFA) when sufficient reducing power is provided. Zero-valent iron (ZVI) is used widely as a reducing agent in environmental remediation applications. This study established that the externally provided reducing power from ZVI oxidation increased the acetate production (approximately 13 times) from CO and the further synthesis of VFA. The effect of ZVI on CO/CO2 conversion was evaluated by quantifying the formation of acetate and butyrate. The carbon and electron balance provide information on the mechanism of C1 gas conversion and chain elongation. These findings highlight a useful intermediate production under the reducing power-limited bioprocesses, such as C1 gas bioconversion.