Experimental gasification of glycerol-impregnated eucalyptus biomass for hydrogen-rich syngas

This study presents an experimental investigation of the gasification performance of eucalyptus biomass impregnated with residual glycerol for hydrogen-enriched syngas production. Eucalyptus–residual glycerol mixtures containing 0, 10, and 20 wt% glycerol were gasified in a semi-industrial-scale downdraft reactor (45 kWth) under controlled operating conditions. Physicochemical characterization revealed that glycerol incorporation significantly modified fuel properties, resulting in a substantial increase in volatile matter and heating value. The higher heating value of the mixtures increased by up to 38% compared to raw eucalyptus biomass. Gas chromatography analysis showed that glycerol addition strongly influenced syngas composition. The mixture containing 20 wt% glycerol exhibited the highest hydrogen concentration, corresponding to a 32.90% increase relative to non-impregnated biomass, with a maximum hydrogen content of 22.29% obtained at 811 °C. The results indicate that glycerol impregnation enhances hydrogen-forming reaction pathways, though it is accompanied by variations in energetic performance parameters. The findings demonstrate that residual glycerol, an abundant byproduct of the biodiesel industry, represents a viable additive for modifying biomass gasification behavior and promoting hydrogen-rich syngas production. This approach provides a promising pathway for industrial residue valorization, contributing to waste management, resource efficiency, and sustainable energy generation within the framework of circular bioeconomy strategies. • Novel engineering validation of glycerol-biomass gasification synergy • Residual glycerol impregnation significantly increased eucalyptus heating value. • Hydrogen concentration increased by 32.90% for the 20 wt% glycerol mixture. • Trade-offs between hydrogen enrichment and CGE were identified.