Thermochemical conversion of biomass to fuels and chemicals: a review of catalysts, catalyst stability, and reaction mechanisms

ABSTRACTWoody biomass can be converted into a synthesis gas, a mixture of H2, CO, and CO2, by gasification. Removal of refractory tars, produced during biomass gasification, requires highly active catalysts that can be applied in-situ during gasification or in secondary catalytic tar cracking reactors. Subsequently, the water-gas-shift (WGS) reaction adjusts the H2 to CO ratio, prior to the synthesis of the desired products (CH4 as renewable natural gas or RNG, alcohols, hydrocarbons, and olefins). Catalysts play a pivotal role in all processing steps, with recent advances in catalyst development discussed herein with an emphasis on catalyst stability, reaction mechanisms, and structure–activity relationships. The economic viability of biomass conversion to fuels and chemicals is also reviewed and shown to be dependent on end-product, location, and government incentives.KEYWORDS: Biomass gasificationmechanismsstability issuessyngas conversiontar crackingWater-gas-shift (WGS) reaction AcknowledgmentsFinancial support from Natural Resources Canada – Clean Growth Program, MITACS, the BC Pulp and Paper BioAlliance, and the Talent Introduction Program of Postdoctoral International Exchange Program (YJ20210238) is gratefully acknowledged.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was supported by the Mitacs; Talent Introduction Program of Postdoctoral International Exchange Program (YJ20210238); Natural Resources - Canada Clean Growth Program; BC Pulp and Paper BioAlliance.