Development of Ni catalysts for tar removal by steam gasification of biomass

Catalytic performance of Ni/CeO2/Al2O3 catalysts prepared by a co-impregnation and a sequential impregnation method in steam gasification of real biomass (cedar wood) was investigated. Especially, Ni/CeO2/Al2O3 catalysts prepared by the co-impregnation method exhibited higher performance than Ni/Al2O3 and Ni/CeO2/Al2O3 prepared by the sequential impregnation method, and the catalysts gave lower yields of coke and tar, and higher yields of gaseous products. The Ni/CeO2/Al2O3 catalysts were characterized by thermogravimetric analysis, temperature-programmed reduction with H2, transmission electron microscopy and extended X-ray absorption fine structure, and the results suggested that the interaction between Ni and CeO2 became stronger by the co-impregnation method than that by sequential method. Judging from both results of catalytic performance and catalyst characterization, it is found that the intimate interaction between Ni and CeO2 can play very important role on the steam gasification of biomass.