Fermentative biohydrogen production from lactate and acetate.
In this study, a continuous-flow stirred tank reactor (CSTR) fed with lactate and acetate was operated to enrich hydrogen-producing bacteria. By varying the influent substrate concentrations and hydraulic retention times (HRT), the volumetric loading rate (VLR) of 55.64 kg-COD/m(3)/day seemed to be optimum for this enriched culture for fermentative hydrogen production from lactate and acetate. The results of batch experiments confirmed that the enriched culture tended to fulfill the e(-) equiv requirement for cell growth at a lower VLR condition (21.77 kg-COD/m(3)/day), while it could largely distribute the e(-) equiv for hydrogen production at a higher VLR condition. However, a maximum lactate/acetate concentration allowed for enriching this culture existed, especially at a lower HRT condition in which wash-out can be an issue for this enriched culture. Finally, the results of cloning and sequencing indicated that Clostridium tyrobutyricum was considered the major hydrogen-producing bacteria in the CSTR fed with lactate and acetate.
Department of Environmental Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan.
Chao-Wei
CW
Wu
Liang-Ming
LM
Whang
Hai-Hsuan
HH
Cheng
Kan-Chi
KC
Chan
D000085:Acetates / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism; D001483:Base Sequence; D019149:Bioreactors; D017931:DNA Primers; D005285:Fermentation; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism*; D016133:Polymerase Chain Reaction
D000085:Acetates; D017931:DNA Primers; D019344:Lactic Acid; D006859:Hydrogen