Insight from the study of acidity and reactivity of Cr2O3 catalyst in propane dehydrogenation: a computational approach

Abstract

By converting low-value commodity fuels into high-value products, like polymer precursors, chemical and other intermediates, the dehydrogenation of light paraffin (such as ethane and propane) into olefins, can add significant value to the refining processes that generate propane. In this study, the parameterised method 3 (PM3) approximation of semi empirical theory was employed to study the acidity and reactivity of chromium (III) oxide catalyst in the dehydrogenation of propane into propylene. Ammonia and pyridine were used computationally as molecular probes for the evaluation of the Lewis acidity of the catalyst sites. The propane adsorption and dissociation activation energies were also evaluated. The study showed that the chromium sites are highly acidic and reactive compared to the oxygen sites. In particular, the study showed that the chromium site is the main active site in the promotion of propane dehydrogenation into propylene, over chromium (III) oxide catalyst.

Keywords: Acidity, Reactivity, Dehydrogenation, Propane, Chromium.