Author/Authors :
Hwang، نويسنده , , Jae-Hoon and Choi، نويسنده , , Jeong-A. and Abou-Shanab، نويسنده , , R.A.I. and Bhatnagar، نويسنده , , Amit and Min، نويسنده , , Booki and Song، نويسنده , , Hocheol and Kumar، نويسنده , , Eva and Choi، نويسنده , , Jaeyoung and Lee، نويسنده , , Eung Seok and Kim، نويسنده , , Yong Je and Um، نويسنده , , Sukkee and Lee، نويسنده , , Dae Sung and Jeon، نويسنده , , Byong-Hun، نويسنده ,
Abstract :
The effects of varying sulfate concentrations with pH on continuous fermentative hydrogen production were studied using anaerobic mixed cultures growing on a glucose substrate in a chemostat reactor. The maximum hydrogen production rate was 2.8 L/day at pH 5.5 and sulfate concentration of 3000 mg/L. Hydrogen production and residual sulfate level decreased with increasing the pH from 5.5 to 6.2. The volatile fatty acids (VFAs) and ethanol fractions in the effluent were in the order of butyric acid (HBu) > acetic acid (HAc) > ethanol > propionic acid (HPr). Fluorescence In Situ Hybridization (FISH) analysis revealed the presence of hydrogen producing bacteria (HPB) under all pH ranges while sulfate reducing bacteria (SRB) were present at pH 5.8 and 6.2. The inhibition in hydrogen production by SRB at pH 6.2 diminished entirely by lowering to pH 5.5, at which activity of SRB is substantially suppressed.
Keywords :
Hydrogen production , Anaerobic mixed microflora , sulfate , Fluorescence in situ hybridization , PH
