Gasification investigations of coal and biomass blends for high purity H2 production with carbon capture potential

Abstract Biomass is carbon-neutral and has the carbon-negative potential if combined with carbon capture and storage (CCS). This study investigated the thermochemical conversion to high-purity hydrogen of a typical lignite (BYH) and seaweed biomass (BS) with carbon capture in a designed fixed-bed reactor at moderate conditions (1 atm, 873 K). High-purity hydrogen of 486.91–801.5 ml/g-blends with suppressed CO2 formation was produced in the alkaline gasification. The alkali can decompose the coal/biomass molecular structures, in-situ capture CO2 and control the gases to high-purity H2 (80.1%–93.2%). The synergistic effect of coal and biomass changes the gas evolution behaviors and impacts the chemical structures of the char. The abundant SiO2 and Al2O3 in the coal can inhibit the catalytic activities of earth alkali metals in the biomass, but not much. These results are significant to the future development of low-carbon renewable energy techniques.