Operando observation of Ni 2P structural changes during catalytic reaction: Effect of H 2S pretreatment

Abstract

In situ X-ray absorption spectroscopy was used to study the effect of H2S pretreatment on the activation of Ni2P catalysts for the thiophene hydrodesulfurization (HDS) reaction. It was found that H2S treatment produced NiS bonds that were slightly longer and that had higher coordination numbers than those formed during reaction. The longer NiS bonds formed by H2S treatment were changed to the shorter NiS bonds by the catalytic reaction, and these shorter bonds were associated with high activity. The work provides evidence that a NiPS phase is active in the HDS reaction. © 2012 The Chemical Society of Japan.