Hydrogen production from steam reforming of simulated bio-oil over Ce-Ni/Co catalyst with in continuous CO_2 capture

摘要

For microsized CaO calcinated from calcium acetate as CO_2 sorbent, the CO_2 adsorption efficiency increased with the increased of temperature, but decreased when the temperature was over 750 ℃, due to the endothermic decomposition of CaCO_3. The decreased CO_2 partial pressure was unfavourable to CO_2 adsorption. The steam reforming of the simulated bio-oil over the Ce-Ni/Co catalyst supported on Al_2O_3 balls was performed, and the optimal results for hydrogen production were obtained at 700 ℃, the S/C ratio of 9 and the L_sHSV of 0.23 h~(-1), with the actual hydrogen yield of 83.8% and the H_2(+CO + CH_4) yield of 94.1%. In the steam reforming experiment with in continuous situ CO_2 capture, the feeding of CaO into the reforming reactor made the hydrogen concentration improved excellently upto 93.3%. However, the H_2 yield decreased at higher CaO/C ratio, mainly because the excessive CaO restrained the contact between the reactants and the catalyst. Besides, the higher S/C ratio decreasing the CO_2 partial pressure, was against the simultaneous CO_2 adsorption, with the optimal S/C ratio of 9.