초록
<P><B>Abstract</B></P> <P>A three-chamber electrodialysis bioreactor comprising fermentation, cathode and anode chambers was proposed to remove <I>in situ</I> volatile fatty acids during hydrogen fermentation. The electrodialysis voltage of 4 V resulted in a volumetric hydrogen productivity of 1878.0 mL/L from the fermentation chamber, which is 55.4% higher than that (1208.5 mL/L) of the control group without voltage applied. Gas production was not observed in the cathode and anode chambers throughout fermentation. By applying different voltages (0–6 V), the hydrogen content accumulated to 54.6%–84.7%, and it exhibited increases of 7.1%–66.4% compared with that of the control. Meanwhile, the maximum concentrations of acetate and butyrate in the fermentation chamber decreased to 10.3 and 13.1 mmol/L at a voltage of 4 V, respectively, which are 68.0% and 62.4% lower than that for the control.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A three-chamber electrodialysis reactor was used to enhance hydrogen fermentation. </LI> <LI> VFAs and bicarbonate were effectively removed from fermentation chamber. </LI> <LI> Electrodialysis reactor improved specific H<SUB>2</SUB> yield up to 55.4% at a voltage of 4 V. </LI> <LI> Electrodialysis reactor enhanced H<SUB>2</SUB> content up to 66.4% with reduced CO<SUB>2</SUB> content. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>