Novel modified olivine supported nickel catalyst for biomass tar steam reforming

摘要

With benzene as a model compound, catalytic steam reforming of biomass gasification tar was tested on a novel nickel/modified olivine catalyst. The catalyst showed a higher activity and a longer lifetime compared with the nickel/olivine catalyst which deactivated rapidly at the space velocity of 0.02mol/(h·gcat) and a steam t°Carbon ratio 1.4. TG-DTA analysis of used catalysts revealed that the nickel/modified olivine catalyst exhibited high resistance to Coking. The olivine support and the nickel catalysts were further characterized by BET surface area, X-ray diffraction (XRD), scanning electron microscopy (SEM) and temperature-programmed reduction (TPR). It was observed that the BET surface area of modified olivine is 3.7 m 2 /g and the apparent porosity is about 32%, whereas the natural calcined olivine is almost nonporous and its surface area is as low as 1.2 m 2 /g. A smaller average size of nickel particles and different nickel oxide phases were found on the nickel/modified olivine. It was speculated that a porous structure of the support and a moderate interaction between nickel and support contribute to the excellent catalytic performance and high coking resistance of the novel catalyst.