Catalytic Steam Gasification of Cellulose Using Reactive Flash Volatilization

Biomass gasification is considered to be one of the most promising technologies to deliver renewable energy. However, tar formation in the gasifier is one of the main challenges. Ni-based catalysts are one of the most effective transition-metal catalysts in biomass gasification for tar cracking and reforming. Alumina-supported Ni, Pt-Ni, Ru-Ni, Re-Ni and Rh-Ni catalysts were tested for their activity in the reactive flash volatilisation (RFV) of cellulose to produce synthesis gas in 50 ms reaction time. RFV is a catalytic gasification process that utilises a high carbon space velocity and mass flow rate with oxygen and steam as gasification agents. Re-Ni, Rh-Ni and Ru-Ni supported catalysts showed a higher gasification efficiency than the other catalysts, which was because of their higher metal surface area, high reducibility and lower CO desorption temperature. The highest gasification efficiency was achieved at 750 °C with a carbon-to-oxygen ratio of 0.6 and a carbon-to-steam ratio of 1.0 without any oxygen breakthrough.