Methane or methanol via catalytic gasification of biomass

Methane and methanol synthesis gas can be produced by steam gasification of biomass in the presence of appropriate catalysts. A 5 cm diameter reactor has been used to determine the desired catalysts and operating temperature. A process development unit (PDU) has demonstrated steam gasification of biomass with catalysts at rates up to 35 kg per hour. Methane yields of 0.28 nm/sup 3/ per kg of dry wood were produced in the small laboratory reactor. Further methanation of the product gas mixture can increase methane yields to 0.33 nm/sup 3//kg. The catalyst system is nickel and silica-alumina. The preferred reactor operating temperature is 500 to 550/sup 0/C. Tests have been at atmospheric pressure. The PDU performance has confirmed results obtained in the laboratory. Methanol synthesis gas can be produced in a single stage reactor at 750 to 850/sup 0/C by steam gasification of wood with silica-alumina and nickel catalysts present. From this gas, up to 0.6 kg of methanol can be produced per kg of wood. Gasification of the wood to produce synthesis gas has been demonstrated in the laboratory scale reactor, but remains to be successfully done using the PDU. Catalyst deactivation rates and regeneration schemes must be determined in order to determine the economic feasibility of wood to methane or methanol processes. Some advantages of catalytic steam gasification of biomass over steam-oxygen gasification are: no oxygen is required for methane or methanol synthesis gas, therefore, no oxygen plant is needed; little or no tar is produced resulting in simpler gas cleaning equipment; no shift reactor is required for methanol synthesis; methanation requirements are low resulting in high conversion efficiency; and yields and efficiencies are greater than obtained by conventional gasification