(745f) Upgrading Biomass Using Low Temperature Plasma

Linear hydrocarbons are not easily obtained from biomass, even after thermochemical deconstruction and upgrading. The established thermochemical methods of deconstructing biomass include pyrolysis and gasification, which provide possible routes to hydrocarbons. The resulting products of biomass thermochemical deconstruction can then be upgraded by catalytic reactions such as hydrodeoxygenation of pyrolysis-oil or Fischer–Tropsch reaction of biomass-derived syngas. A major challenge with these routes is that they produce highly heterogeneous product mixtures with low selectively. Catalyst fouling and inactivation is also problematic. A single-step process, which does not require metal catalysts, to produce oxygen-free hydrocarbons with high selectivity would be attractive. In this talk, we will report on our recent work to upgrade lignocellulosic biomass into deoxygenated hydrocarbons in a single step using a catalyst-free, low temperature plasma process. Effects of process parameters such as plasma power, pressure, gas composition (e.g. H₂ fraction), and biomass feedstock composition (e.g. lignin vs. cellulose) will be discussed. The evidence demonstrates that the plasma is capable of rapidly generating volatile deoxygenated hydrocarbons with high yield and selectivity without the need for catalysts. A preliminary technoeconomic assessment will be presented.