Time-of-flight secondary ion-mass spectrometry as a new technique for the investigations of the deactivation process of hydrodechlorination catalysts

Abstract

Time-of-flight secondary ion-mass spectrometry (ToF-SIMS) was applied to investigations of the deactivation process of hydrodechlorination catalysts. It appeared that, owing to the use of the ToF-SIMS technique, simultaneous monitoring of various reasons for catalyst deactivation was possible in one measurement. As a model catalyst, the Pd/Al2O3 sample was chosen. ToF-SIMS studies revealed an increase in the amount of Cl and PdCl2 on the catalyst surface during the hydrodechlorination reaction. Moreover, a drop in the quantity of surface-accessible Pd was observed.