Hydration of cyclohexene in sub-critical water over WOx–ZrO2 catalysts

WOx/ZrO2 catalyzed hydration of cyclohexene in sub-critical water was experimentally investigated. The migration of reaction zone into sub-critical water makes it possible to run the hydration in a single liquid phase, and the reaction is free from the limitation of liquid–liquid phase mass transfer to hydration kinetics. The severe hydrothermal environments favor the transformation of surface active sites on WOx–ZrO2 catalysts to Brønsted acid centers of stronger acidity, which are highly effective for the hydration of cyclohexene to the desired product cyclohexanol.

Graphical AbstractWOx–ZrO2 catalysts present a highly selective activity to the hydration of cyclohexene to cyclohexanol conducted in sub-critical water, and the reaction free from the liquid–liquid mass transfer is greatly accelerated.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch Highlights► WOx-ZrO2 catalyzed hydration of cyclohexene is operated in a single liquid phase. ► Surface WOx species of stronger acidity are formed in the hydrothermal environments. ► WOx-ZrO2 is effective to the hydration of cyclohexene to cyclohexanol in sub-CW.