Enhanced Hydrogen Production from Steam Reforming of Vegetable Oil over Bimodal ZrO2-SiO2 Supported Ni Catalyst

摘要

abstract_textpBimodal (ZrO2-SiO2-B) support was successfully fabricated by self-assembly of nanosized ZrO2 inside pores of a commercial silica gel Q-30. For comparison, a unimodal (ZrO2-SiO2-U) support was prepared by impregnation of Q-30 with zirconium nitrate. Ni supported bimodal and unimodal ZrO2-SiO2, and pristine SiO2 (Q-30 and Q-3) catalysts were comparatively studied in steam reforming of vegetable oil to hydrogen. The support and catalyst were analyzed by various techniques, such as N-2 physisorption, XRD, TPR, H-2 chemisorption and TGA. Characterization results indicated that bimodal support show-ing increased BET surface area was beneficial for the dispersion of Ni species. TPR result showed that the incorporation of ZrO2 improved the reducibility of NiO and enhanced the metalsupport interaction, simultaneously. Among all catalyst studied bimodal Ni/ZrO2-SiO2-B catalyst exhibited highest oil conversion and H-2 formation rate with good stability due to the improved Ni dispersion, enhanced Ni-support interaction, as well as facilitated diffusion of reactant and products, benefiting from bimodal structure and promotional effect of ZrO2./p/abstract_text