초록
<P>The effects of antifoaming agents on fermentative hydrogen production using galactose in batch and continuous operations were investigated. Batch hydrogen production assays with LS-303 (dimethylpolysiloxane), LG-109 (polyalkylene), LG-126 (polyoxyethylenealkylene), and LG-299 (polyether) showed that the doses and types of antifoaming agents played a significant role in hydrogen production. During batch tests, LS-303 at 100 mu L/L resulted in the maximum hydrogen production rate (HPR) and hydrogen yield (HY) of 2.5 L/L-d and 1.08 mol H-2/mol galactose(added), respectively. The following continuously stirred tank reactor operated at 12 h HRT with LS-303 at 100 mu L/L showed a stable HPR and HY of 4.9 L/L-d and 1.17 mol H-2/mol galactoseadded, respectively, which were higher than those found for the control reactor. Microbial community analysis supported the alterations in H-2 generation under different operating conditions and the stimulatory impact of certain antifoaming chemicals on H-2 production was demonstrated. (C) 2016 Elsevier Ltd. All rights reserved.</P>