How syngas composition affects catalytic steam reforming of tars: An analysis using toluene as model compound

Tar removal by catalytic steam reforming has an important role to play in gasification hot gas treatment. Despite the importance of understanding the influence gas atmosphere has on this reaction, the effect of a full syngas mixture has not been comprehensively investigated. This study aims to bridge that gap by analyzing the effect of each component as well as their combinations on steam reforming of toluene as biomass gasification tar model over a Ni/Al2O3 catalyst. It has been found that H2, CO and CO2 have minor inhibitory effects, slightly decreasing the initial toluene conversion. On the other hand, while CO and CO2 do not lead to catalyst deactivation, H2 and CH4 deactivate Ni/Al2O3 by promoting coke deposition. Only 3 vol.% of CH4 can significantly increase deactivation, despite being insignificant with toluene or CH4 separately. The joint presence of CH4 and H2 causes further drops in conversion with time on stream.