(583bl) Hydration of Cyclohexene Over Niobic Acid Modified Amphiphilic Zeolite Catalyst

Amphiphilic solid catalysts were prepared by treating HZSM-5 zeolite with cyclohexenyl trichlorosilane and then modified by niobic acid. The impact between the catalytic activity and the acidic and hydrophobic property of the catalyst is investigated. The catalysts were characterized by BET, TPD and XRD etc. It confirmed that niobic acid impregnation can effectively increase the number of active centers on the surface of HZSM-5 zeolite and reduce the diffusion resistance of cyclohexene to the active center, which leaded to an improved reactivity. This amphiphilic HZSM-5 zeolite also exhibited a much higher catalytic activity than the parent HZSM-5 zeolite in the hydration of cyclohexene phase-boundary reaction even without adding co-solvents or stirring. The modified amphiphilic zeolite catalyst, as Phase-boundary catalyst, reduces energy consumption, and the separation between catalyst and reaction solution become easier. Besides, it did not form a catalyst emulsion, which avoided the serious loss of catalysts in the industry production.