Cleaner production of hydrogen and syngas from catalytic steam palm kernel shell gasification using CaO sorbent and coal bottom ash as a catalyst

The catalytic-sorbent based steam gasification of palm kernel shell is examined in a pilot-scale integrated fluidized-bed gasifier and fixed-bed reactor using coal bottom ash as a novel catalyst for cleaner hydrogen and syngas production. Itenhances tar cracking and enriches hydrogen composition as an effective catalyst. The effect of temperature, steam/biomass ratio,CaO/biomass ratio, and coal bottom ash wt % is evaluated for hydrogen yield, syngas composition, lower and higher heatingvalues, and efficiency of carbon conversion, gasification, and cold gas. Steam is the most influential factor, and it enhances thehydrogen yield from 35.7 to 79.77%. The CaO/biomass ratio and coal bottom ash have a positive impact on hydrogen andsyngas yield with CO 2 sorption and catalytic effect, respectively. The enhancement of hydrogen and syngas composition is due tothe catalytic effect of Fe, Al, Mg, and Ca contents present in coal bottom ash as detected by X-ray fluorescence (XRF). Themetals content of Fe, Al, Mg, and Ca increased the hydrogen content by enhancing tar cracking, methane reforming, and watergas shift reaction. Maximum hydrogen and syngas production of 79.77 and 85.55 vol %, respectively, were achieved at atemperature of 692 °C with 1.5 steam/biomass ratio and 0.07 wt % coal bottom ash.