Thermodynamic analysis of hydrogen production from model compounds of bio-oil through steam reforming



With the minimization of the Gibb's free energy, the thermodynamical analysis of the steam reforming processes for the four typical model compounds (ethanol, acetic acid, acetone, and phenol) of bio-oil was systematically performed. In the steam reforming process, the four model compounds can be completely converted. The higher hydrogen yields of the four compounds were obtained via steam reforming than via thermal decomposition. The hydrogen yields first increased and then remained constant and even decreased with temperature, monotonically decreased with the pressure increase, and obviously increased with the steam to carbon ratio. As the steam to carbon ratio rose, the temperatures of the maximum hydrogen yields move afterward to low temperature. When the S/C ratio was 6, the increase rate of hydrogen was decreased. In the co-existence of CaO/CO2/H2O, the reaction between CaO and CO2 was dominant to the reaction between CaO and H2O. By adding CaO, a CO2 sorbent in the steam reforming system, both the yields and the concentration of hydrogen were obviously more pronounced than the processes without CaO. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 1008–1016, 2014