CATALYZED STEAM GASIFICATION OF BIOMASS

Steam gasification of wood in the presence of catalysts was investigated. Two methods for wood/catalyst contacting were used: dry mixing of the wood and solid catalyst and impregnation of the wood with catalyst. Impregnation gave greater yields and rates than dry mixing and was used throughout the remainder of the investigation. Catalysts used included potassium carbonate, sodium carbonate, trona and borax, in order of their effectiveness at all temperatures. The gasification process with and without catalyst occurred in 2 stages: a rapid pyrolysis immediately after heat-up and reaction of steam with the char residue. The steam/char reaction obeyed pseudo-1st-order kinetics.