PRODUCTION OF ACETIC ACID FROM HYDROGEN AND CARBON DIOXIDE BY CLOSTRIDIUM SPECIES ATCC 29797

Abstract

Abstract Clostridium sp. ATCC 29797 converts H2 and CO2 to acetic acid in stationary phase in almost 100% yield. The resting cells are stable for up to 300 h and produce acetate to a final product concentration of 221 mM. The specific productivity of acetate during the stationary phase appears limited by the specific activity of hydrogenase. A high pressure fermentor was constructed to investigate the use of pressure, as a general strategy, for increasing the rates of microbial syngas conversions. Fermentations were conducted at pressures up to 1000 psig using various mixtures of H2 and CO2. The use of high pressure proved to be an effective method for eliminating gas transfer resistances and increasing the volumetric productivity. Hydrostatic pressure had little effect on the specific productivity of acetate, however, high partial pressures of hydrogen caused the specific productivity and total acetate accumulated to decrease. High pressures of hydrogen also caused a decrease in the specific activity of ...