(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.