BioChem - DOS

The role of pH control on biohydrogen production by single stage hybrid dark- and photo-fermentation

Bioresource technology : biomass, bioenergy, biowastes, conversion technologies, biotransformations, production technologies

Zagrodnik, R.; Laniecki, M.

The role of pH control on biohydrogen production by co-culture of dark-fermentative Clostridium acetobutylicum and photofermentative Rhodobacter sphaeroides was studied. Single stage dark fermentation, photofermentation and hybrid co-culture systems were studied at different values of controlled and uncontrolled pH. Increasing pH during dark fermentation resulted in lower hydrogen production rate (HPR) and longer lag time for both controlled and uncontrolled conditions. However, it only slightly affected cumulative H<SUB>2</SUB> volume. Results have shown that pH control at pH 7.5 increased photofermentative hydrogen production from 0.966 to 2.502L H<SUB>2</SUB>/L<SUB>medium</SUB> when compared to uncontrolled process. Fixed pH value has proven to be an important control strategy also for the hybrid process and resulted in obtaining balanced co-culture of dark and photofermentative bacteria. Control of pH at 7.0 was found optimum for bacteria cooperation in the co-culture what resulted in obtaining 2.533L H<SUB>2</SUB>/L<SUB>medium</SUB> and H<SUB>2</SUB> yield of 6.22mol H<SUB>2</SUB>/mol glucose.

2015

Elsevier Applied Science

0960-8524

194

pp.187-195

10.1016/j.biortech.2015.07.028

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART72444180

Biohydrogen; Combined fermentation; pH control; Photofermentation; Dark fermentation