Enhanced propane dehydrogenation performance using bimetallic-modified GaPt/SiO2-Al2O3 with ultralow-loading Pt

Abstract

Propane dehydrogenation (PDH) is used to increase propylene production and to produce hydrogen as a by-product. Despite the widespread utilisation of Pt-loaded catalysts in industrial PDH operations, challenges such as excessive noble metal loading and coking persist in the face of rigorous reaction conditions. These hindrances limit to achieving the optimal economic efficiency. In this work, we report a method aimed at reducing Pt loading to only 0.05 wt% through synergistic modification of GaPt catalysts loaded on SiO2-Al2O3 supports (i.e. SIRAL) with K and Ce. The resulting catalysts exhibit remarkable stability and elevated activity for propane dehydrogenation. The K+ and SiO2 could modulate the support surface acidity and immobilizes the active tetrahedral Ga3+ sites, which improves the catalytic performance and reduce coke deposition. Furthermore, the inclusion of Ce decreases the electron density of the Pt species, stabilizing the atomically dispersed Pt and enhances the formation of active Pt sites, which effectively impedes the Pt agglomeration. As a result, the GaPtKCe/SIRAL10 catalyst demonstrates excellent catalytic performance, achieving 47% propane conversion and >96% propylene selectivity, while maintaining notable stability with 0.016 h−1 deactivation rate constant at 580 °C, even without hydrogen co-feed.