Advancing hydrogen production: The synergy of pretreatment and boron catalysts

This study evaluates the production of hydrogen-rich synthesis gas from the energy crop Miscanthus x giganteus and municipal wastewater treatment sludge. The effects of biomass pretreatment, gasification conditions (temperature, catalyst content, and catalyst-to-biomass ratio), and hydrogen yield were investigated. Both catalytic and non-catalytic biomass steam gasification methods were explored. Catalytic biomass steam gasification employed a newly developed catalyst using boron-supported alkali-based materials and biomass feedstock, aiming to achieve a higher hydrogen gas composition in the product gas compared to non-catalytic steam gasification. The composition of syngas produced by biomass steam gasification was analyzed to determine the H₂ and CO components, as well as other gas byproducts. The optimization study, utilizing the Box-Behnken Design, identified parameters influencing H₂ generation and the catalytic impact on gasification efficiency. In catalytic gasification experiments using hydrochar derived from miscanthus as the model biomass, optimal conditions for H₂ concentration were found to be 900 °C, 10.0 % boron content, and a biomass-to-catalyst ratio of 0.65. The results demonstrated a hydrogen content of 62.88 % in the product gas, highlighting the significant role of the catalyst in tar removal.