Preparation of new type of Sn-Pt/SiO2 catalysts for carbonyl activation

The paper is aimed to demonstrate how the activity and selectivity of a Pt/SiO2 catalyst can be tailored by introduction of tin either to hydrogenate the aldehyde group in alpha,beta-unsaturated aldehydes (UA) or oxidize carbon monoxide at room temperature. In this paper general aspects of catalyst design based on the use of tin tetraalkyls are described in detail. Results summarized in this work show that upon using new approaches for anchoring tin into platinum high Sn-anch/Pt-s can be achieved. The experimental evidences indicate also that the hydrogenation of the aldehyde group in a,p-unsaturated aldehydes and oxidation of CO requires in situ formed ''Sn4+-Pt ensemble'' sites to activate either the carbonyl group or the CO molecule. (C) 2002 Elsevier Science B.V. All rights reserved.