Abstract:
Raw biogas can be an alternative feedstock to pure methane (CH4) for methanol production. In this inves tigation, we evaluated the methanol production potential of Methylosinus sporium from raw biogas orig inated from an anaerobic digester. Furthermore, the roles of different gases in methanol production were
investigated using synthetic gas mixtures of CH4, carbon dioxide (CO2), and hydrogen (H2). Maximum
methanol production was 5.13, 4.35, 6.28, 7.16, 0.38, and 0.36 mM from raw biogas, CH4:CO2, CH4:H2,
CH4:CO2:H2, CO2, and CO2:H2, respectively. Supplementation of H2 into raw biogas increased methanol
production up to 3.5-fold. Additionally, covalent immobilization of M. sporium on chitosan resulted in
higher methanol production from raw biogas. This study provides a suitable approach to improve metha nol production using low cost raw biogas as a feed containing high concentrations of H2S (0.13%). To our
knowledge, this is the first report on methanol production from raw biogas, using immobilized cells of
methanotrophs.
