Rh-perovskite catalysts for conversion of tar from biomass pyrolysis

Alumina supported Rh-LaCoO3 has been investigated for the catalytic conversion of tar produced by biomass pyrolysis into hydrogen-rich gas. A double fixed bed reactor system, equipped with a microchromatograph for the analysis of permanent gases and a chromatograph for the analysis of condensable species, has been developed to perform a preliminary screening of catalysts with different compositions by contacting them at 700 oC with a real mixture of gas and volatiles produced by biomass decomposition. Biomass has been characterized by elemental, proximate and thermal analysis. Redox properties of catalysts, estimated with H2 Temperature Programmed Reduction (TPR) analysis, have been correlated to the catalytic performance towards tar conversion. All catalysts completely convert tars into syngas with small quantities of CH4 and CO2, more reducible catalysts also strongly improve tar reforming and inhibit coke deposition.