Removal of Headspace CO2 Increases Biological Hydrogen Production by C. acetobutylicum

Abstract

The effect of removal of resultant gas resulted in enhancement of the H2 yield. The technique of CO2 scavenging resulted in H2 yield being improved from 408 mL g(-1) to reach the maximum of 422 mL g'. The highest hydrogen productivity of 87.9 ml L(-1) h(-1) was obtained by CO2 scavenging. Biomass concentration was enhanced to 1.47 g L(-1), Y(P,X) of 287 ml g(-1) L(-1), Y(X/S) of 0.294 and Y(H2/s) of 0.0377 by the use of CO2 scavenging. The results suggested that the presence of the gaseous products in fermentation medium and headspace adversely effect biomass growth and hydrogen production.

CO2 Mass Transfer Induced through an Airlift Loop by a Microbubble Cloud Generated by Fluidic Oscillation

“…Park et al 19 demonstrated that reducing the concentration of CO 2 from 24.5% into 5.3% in the headspace caused an increase in the hydrogen yield by 43%. Alshiyab et al 20 indicated that there is an increase in the hydrogen yield when the partial pressure of carbon dioxide is decreased.…”

“…For instance, the production of biohydrogen from glucose has been the subject of considerable investigation for the efficacy of gaseous product removal. − normalC 6 normalH 12 normalO 6 + 2 normalH 2 normalO → bacteria 2 normalC normalH 3 COOH + 2 CO 2 + 4 normalH 2 Tanisho et al found that hydrogen production increased when the partial pressure of CO 2 decreased. Park et al demonstrated that reducing the concentration of CO 2 from 24.5% into 5.3% in the headspace caused an increase in the hydrogen yield by 43%.…”