Influence of carbonates and phosphates on fermentative biohydrogen production of Biohydrogenbacterium R3 sp. nov.

This study investigated the effects of phosphates and carbonates (NH4HCO3, NaHCO3, Na2CO3, K2HPO4, KH2PO4, NaH2PO4 and Na2HPO4) on the hydrogen production efficiency and cell growth to Biohydrogenbacterium R3 sp.nov. It was indicated that the carbonates could buffer the pH in reactor better and the phosphates could promote the hydrogen production obviously. When Na2HPO4 and K2HPO4 were added into the reactor, the hydrogen production and content reached the maximum of 1978.56 mL, 44.1% and 2160.9 mL, 45.8%, respectively. The pH and cell weight achieved 3.28, 1.03 g·L-1 and 3.41, 1.21 g·L-1, respectively. When Na2HPO4 was added into the reactor, the ethanol and acetic acid were 4841.49 mg·L-1 and 2064.94 mg·L-1, respectively, while when Na2CO3 was added into the reactor, the hydrogen production, hydrogen content, cell weight, pH, ethanol and acetic acid were 1064.42 mL, 35.96%, 1.23 g·L-1, 3.81, 3862.21 mg·L-1 and 1930.86 mg·L-1, respectively.