Zirconia catalysts (ZrO2 and Na-ZrO2) for the conversion of phenethyl phenyl ether (PPE) in supercritical water

Abstract

In this study, the mesoporous ZrO2 and Na-ZrO2 were examined as heterogeneous solid catalysts under supercritical water for the beta-ether bond scission of phenethyl phenyl ether (PPE). Na-ZrO2 was more efficient than ZrO2 in the dissociation of PPE. Yields of phenol and styrene were 39% and 16%, respectively, under 97% PPE conversion when 2.5 wt.% of Na-ZrO2 catalyst was applied to a batch reactor filled with supercritical water (400 degrees C, 20 bar H-2 (initial pressure)) containing 2.5 wt.% PPE. The characterization revealed that the activities of ZrO2 and Na-ZrO2 were closely associated with the textural and acid/base properties of the catalysts. Notably, the reaction pathway and product distribution were determined by the concentration of acid and base sites on the catalyst's surface. (C) 2015 Elsevier B.V. All rights reserved.