PtIn Alloy Supported on Y2O3-Modified δ-Al2O3 as a Propane Dehydrogenation Catalyst

Propylene production via propane dehydrogenation (PDH) over supported platinum (Pt) catalysts is a vital industrial process. However, rapid catalyst deactivation due to coking necessitates periodic regeneration under harsh oxidative conditions. While alloying Pt with transition metals significantly reduces coking, these alloy catalysts often exhibit poor regeneration stability. In this study, we demonstrate that supporting PtIn nanoparticles on Y2O3-modified δ-Al2O3 yields a PDH catalyst with significantly improved activity and stability. This catalyst achieves propane conversion rates close to the thermodynamic equilibrium at an ultralow Pt loading of 0.1 wt %, along with high propylene selectivity. Notably, this catalyst also exhibits remarkable regeneration stability. Through reaction-regeneration cycling experiments with various catalyst formulations, we reveal that the alloy effects between Pt and In are primarily responsible for enhanced catalyst stability under steady-state reaction conditions by suppressing coke formation. Meanwhile, the incorporation of Y2O3 as a support component significantly improves stability during regeneration. Density functional theory (DFT) calculations further elucidate the key factors contributing to the enhanced anticoking properties of the catalyst under PDH reaction conditions.