Hybrid-functional material for sorption-enhanced hydrogen-rich syngas production from biomass: Effect of material preparation process

Abstract

Pyrolysis of waste biomass sawdust coupled with sorption-enhanced catalytic steam reforming of the pyrolysis gases has been investigated using a novel Ni–CaO–Ca2SiO4 hybrid-functional material for enhanced hydrogen production. Using hybrid stabilized materials with integrated sorption and catalysis functions overcomes the thermodynamic constraint of the reforming reaction equilibrium. The Ni–CaO–Ca2SiO4 hybrid-functional material was prepared under different catalyst drying methods to determine the influence on hydrogen yield. In addition, the process parameters of water injection rate, and catalytic temperature were investigated to optimize the process. The results showed that the presence of Ni–CaO–Ca2SiO4 significantly improved the yield and volume fraction of syngas. The spray-dried hybrid-functional material was shown to be the most effective in terms of H2 yield and purity in the syngas owing to its relatively high stability and higher surface area. The Ni–CaO–Ca2SiO4 material prepared using spray drying gave the highest H2 yield of 25.75 mmol gbiomass−1 that was eight times higher than the material-free test at a reforming temperature of 850 °C and water injection rate of 5 mL h−1. Furthermore, the highest yield of syngas (H2 and CO) was also achieved under these conditions, and where the optimal calorific value of the total gaseous products was 10.63 kJ m−3.