Preparation of ordered mesoporous alumina and its catalytic application in metathesis of butene

Ordered mesoporous alumina (OMA) with high surface area, large pore volume, and narrow pore-size distribution was synthesized from organic aluminum precursors and anionic templates; the influence of various preparation parameters such as hydrolysis speed of the aluminum precursor, chain length of the carboxylic templates and washing medium on the properties of as-synthesized OMA was investigated. With OMA as support, rhenium-based catalyst was prepared by incipient-wetness impregnation method and used in the metathesis of butene to propene. The results showed that increasing hydrolysis speed of the aluminum precursor as well as using ethanol as the washing medium are beneficial to the formation of the organized pore structure; the pore volume and pore diameter of as-synthesized OMA increase with an increase of the chain length of the carboxylic templates used here. Compared with the rhenium catalyst supported on conventional mesoporous alumina, the rhenium-based catalyst prepared with OMA as the support exhibits better performance in the metathesis of butane, i.e. higher selectivity to propene and longer catalytic life; the conversion of butane and selectivity to propene reach 50% and 60%, respectively.