Catalyst development for the gasification of biomass in the dual-bed gasifier

A dual-bed gasifier system combined with catalysts was evaluated in the catalytic gasification of cedar wood at low temperatures (823-973 K). The dual-bed gasifier consisted of a primary-bed section for pyrolysis of biomass and separation of pyrolyzed gas and tar from solid products and a secondary-catalytic tar reformer. Catalyst development was carried out on the basis of Rh/CeO2/SiO2, which has been developed for the higher conversion of carbon to gas and higher yield of CO + H-2 + CH4. We have also carried out the optimization of reaction conditions. Especially, the tar derived from maximum of 250 mg biomass/min can be totally converted to the gas product by 3 g catalyst in this system using ER = 0.25 of total carbon present in the biomass. This performance was much higher than that over commercial steam reforming catalyst. In addition, the amount of coke deposited on Rh/CeO2/SiO2 was much smaller. In the dual-bed system combined with excellent catalysts, almost all the tar can be converted to syngas at lower temperature than that needed by the conventional method with high energy efficiency. (C) 2003 Published by Elsevier B.V.