Effect of Temperature on Sorption-Enhanced H2 Production from Biomass Gasification Using Alkaline Earth Sorbents

In this study, the H-2 production from the gasification of a sugarcanes leaves with alkaline earth sorbents was investigated in a two-stage fixed bed reactor. The alkaline sorbents, including CaO/gamma-Al2O3, MgO/gamma-Al2O3 and CaO-MgO/gamma-Al2O3, were prepared by an excess solution impregnation method. The properties of fresh and used catalysts were contemplated by the XRD. The gasification was performed at the temperature between 300 and 800 degrees C. The results show that the optimum condition was different for CaO/gamma-Al2O3 and MgO/gamma-Al2O3. The MgO/gamma-Al2O3, shows the highest H-2 yield and the lowest CO2 yield at the lower gasification temperature (300 degrees C) than the CaO/gamma-Al2O3 (600 degrees C). Both CaO and MgO on gamma-Al2O3 can promote sorption enhanced H-2 production together at the gasification temperature of 500 degrees C. However, the applicable gasification temperature for CaO-MgO/gamma-Al2O3 was observed at the temperature of 600 degrees C. The results could be concluded that the CaO is more sufficient sorbent and the MgO is more suitable promoter for enhanced H-2 production in pyrolysis-gasification of biomass.