Hydrogen Transfer Activity of Tin-Incorporated Mesoporous Silica

Abstract

Preparation procedure of tin-incorporated in mesopores of MCM-41 has been studied for reduction of acetophenone to 1-phenylethanol. Tin was incorporated into the mesopores of MCM-41 by a template ion exchange (TIE in the following) method. Almost 20 wt% of tin was loaded in the mesopores and about 70% of template was still remained together. Calcination treatment to remove the residual template ions brought about significant collapse of the periodical hexagonal structure of MCM-41 and decrease of surface area because of heat of combustion of the template in the pores accompanying with sintering of incorporated tin. We have investigated the procedure to remove the template from the MCM-41 by rinsing with HCl before or after the tin incorporation to avoid vigorous exothermic combustion during the calcination. Almost 70–80% of template was liberated by the rinse with HCl. The hexagonal structure and surface area were maintained after tin incorporation. The rinse with HCl aqueous solution before the tin incorporation brought about an enhancement of specific activity, formation rate of 1-phenylethanol from acetophenone per incorporated amount of tin. The rinse of HCl before the incorporation increased the specific activity by a factor of 2–3.