Hydrogenation of crotonaldehyde and butyraldehyde on silica supported Pt and PtSn catalysts: A drifts study

A DRIFTS “in situ” study on Pt and PtSn catalysts used in the crotonaldehyde and butyraldehyde hydrogenation was carried out in this work. Results show that, on Pt/SiO2 catalyst a decarbonylation process takes place during the initial reaction minutes, causing an instantaneous and irreversible deactivation. The tin addition improves the stability of the resulting catalyst due to the inhibition of CO formation. Bands assigned to the presence of superficial olefinic species allow to explain the deactivation observed, which is more important in the case of butyraldehyde hydrogenation. In the crotonaldehyde hydrogenation with PtSn/SiO2 catalyst, the band at 1651 cm−1 is assigned to CO strongly coordinated, explaining the high selectivity to UOL of this catalytic system.