Converting Biomass Derived Synthetic Gas to Fuels via Fisher-Tropsch Synthesis

Abstract This article reviews the methanol synthesis and Fischer–Tropsch synthesis (FTS) from synthesis gas obtained by gasification of biomass. Synthesis gas includes mainly hydrogen and carbon monoxide which is also called as syngas (H2 + CO). Methanol can be produced from hydrogen-carbon oxide mixtures by means of the catalytic reaction of carbon monoxide and some carbon dioxide with hydrogen. Copper-zinc and chrome-zinc catalysts are used in industrial methanol production. Bio-syngas is a gas rich in CO and H2 obtained by gasification of biomass. The aim of FTS is synthesis of long-chain hydrocarbons from CO and H2 gas mixture. The products from FTS are mainly aliphatic straight-chain hydrocarbons (CxHy). Besides the CxHy also branched hydrocarbons, unsaturated hydrocarbons, and primary alcohols are formed in minor quantities. The product distribution obtained from FTS includes the light hydrocarbons methane (CH4), ethene (C2H4) and ethane (C2H5), LPG (C3–C4, propane and butane), gasoline (C5–C12), diesel fuel (C13–C22), and light and waxes (C23–C33). The distribution of the products depends on the catalyst and the process parameters such as temperature, pressure, and residence time.