Recent advances in thermochemical conversion of woody biomass for production of green hydrogen and CO2 capture: A review

Hydrogen as a clean energy carrier has attracted great interests world-wide for substitution of fossil fuels and for abatement of the climate change concerns. However, green hydrogen from renewable resources is less than 0.1% at present in the world hydrogen production and this is largely from water electrolysis which is beneficial only when renewable electricity is used. Hydrogen production from diverse renewable resources is desirable. This review presents recent advances in hydrogen production from woody biomass through biomass steam gasification, producer gas processing and H₂/CO₂ separation. The producer gas processing includes steam-methane reforming (SMR) and water-gas shift (WGS) reactions to convert CH₄ and CO in the producer gas to H₂ and CO₂. The H₂ storage discussed using liquid carrier through hydrogenation is also discussed. The CO₂ capture prior to the SMR is investigated to enhance H₂ yield in the SMR and the WGS reactions.