The Nature of Active Sites on Zirconia Modified by Organosilylation for Isomerization and Hydrogenation of olefin

Abstract

The surface modification of acid-base oxide catalysts with organic fragment is a prominent approach to introduce novel functionalities such as binding, adsorption, and catalytic properties. Reported herein is an application of this methodology where we have modified ZrO₂ with PhSiH₃ and  Et₂SiH₂. It was found that the surface silylation of ZrO₂ with PhSiH₃ and  Et₂SiH₂ increased the activity for 1-butene isomerization and for hydrogenation. Titrative poisoning experiments and competitive isomerization were carried out to reveal the nature of both active sites and adsorbed olefin. Coupled with the activity data, the active sites density, and relative adsorption constant of olefin, the role of phenylsilyl group was discussed in terms of electronic effects and Siegel model.