(583cx) Production of Hydrogen Via Steam-Reforming Reactions of Bio-Oil Over Nickel Based Catalysts
The growing energy demand and environmental awareness have increased interest for hydrogen. Hydrogen production from water using sunlight is still expensive while bio-oil derived from biomass is a potential source. Nickel-based catalysts are considered as one of the most promising and economical catalysts for production of H2 via the steam reforming of bio-oil. The challenge for this metal is the coke formation which leads to deactivation of catalyst.
This study focuses on the use of nickel/HZSM-5 catalysts for the steam reforming of model compounds of bio-oil in a fixed-bed reactor. The catalyst powders were activated by reducing in H2 atmosphere and characterized by temperature programmed reduction and scanning electron microscopy. Phenol and ethanol were steam reformed in the temperature ranges from 400 to 500 oC and from 750 to 820 oC. The gas phase products were analyzed by GC and the liquid phase products (oil phase and water phase) were analyzed by GC–MS. Quick deactivations in the first 5 hours were observed in the lower temperature range indicating no steam reforming reactions occurred. All catalysts showed high selectivity toward hydrogen in temperature range from 750 to 820 ℃. SEM showed coke formation on the surface of catalysts. Interestingly, the yield and selectivity toward hydrogen were slightly affected. The reaction mechanism over Ni/HZSM-5 in the presence of carbon was proposed.