Mechanism of hydrogen production in biomass gasification catalyzed by K+-modified cement clinker

Catalysts play a pivotal role in the biomass gasification process. This study investigated the use of K + -modified cement clinker catalysts for biomass gasification, aimed at producing hydrogen-rich synthesis gas. Catalysts with K/cement clinker (Cm) concentrations of 5 %, 10 %, 15 %, and 20 % were prepared using the impregnation method. The as-prepared catalysts were characterized through Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The effects of K + -modified cement clinker concentration, biomass gasification temperature, and biomass-to-catalyst ratio on product yield were examined through gasification experiments conducted in a bubbling bed reactor. The results indicated that K + -loaded cement clinker considerably enhanced catalytic activity. At a temperature of 900 °C, K + concentration of 15 % and a biomass-to-catalyst ratio of 5:2, the hydrogen yield reached 47.2 g/kg, representing a 240 % increase compared to hydrogen production from pure biomass gasification. • A new catalyst was prepared using cement clinker and K. • The hydrogen production rate was 47.2 g/kg under optimal conditions. • The K-impregnated cement clinker process yielded Ca(OH)₂ and K₂Ca(CO₃)₂ fractions. • Ca(OH)₂ and K₂Ca(CO₃)₂ are the main components of the catalyzed reaction