Particulate compositions are described comprising an intimate mixture of a biomass char producedfrom the combustion of a biomass, such as switchgrass or hybrid poplar, with at least a second carbonaceous material, such as petroleum coke or coal, and, optionally a gasification catalyst, for gasification in the presence of steam to yield a plurality of gases including methane and at least one or more of hydrogen, carbon monoxide, and other higher hydrocarbons are formed. Processes are also provided for the preparation of the particulate compositions and converting the particulate composition into a plurality of gaseous products.