Oxidative catalytic steam gasification of sugarcane bagasse for hydrogen rich syngas production

Abstract

Reactive Flash Volatilization (RFV) is an emerging thermochemical method to produce tar free hydrogen rich syngas from waste biomass at relatively lower temperature (<900 °C) in a single stage catalytic reactor within a millisecond residence time. Here, we show catalytic RFV of bagasse using Ru, Rh, Pd, or Re promoted Ni/Al2O3 catalysts under steam rich and oxygen deficient environment. The optimum reaction conditions were found to be 800 °C, steam to carbon ratio = 1.7 and carbon to oxygen ratio = 0.6. Rh–Ni/Al2O3 performed the best, resulting in highest hydrogen concentration in the synthesis gas at 54.8%, with a corresponding yield of 106.4 g-H2/kg bagasse. A carbon conversion efficiency of 99.96% was achieved using Rh–Ni, followed by Ru–Ni, Pd–Ni, Re–Ni and mono metallic Ni catalyst in that order. Alkali and Alkaline Earth Metal species present in the bagasse ash and char, that deposited on the catalyst, was found to enhance its activity and stability. The hydrogen yield from bagasse was higher than previously reported woody biomass and comparable to the microalgae.