Fabrication of highly dispersed Pt-based catalysts on γ-Al2O3 supported perovskite Nano islands: High durability and tolerance to coke deposition in propane dehydrogenation

A series of novel γ -Al 2 O 3 supported Pt In bimetallic catalysts were prepared by perovskite (PTO) lattice interstitial confined reduction and compared with industrial catalyst PtIn/ γ -Al 2 O 3 in the propane dehydrogenation to propene . The physics-chemistry properties of all catalysts and precursors were characterized by BET, NH 3 -TPD, TPR, XRD , TEM , STEM-EDS, XPS , TG and O 2 -TPO techniques. The results show that the metal ions of Pt 4+ and In 3+ confined in PTO lattice interstitial sites were more easily reduced than those confined in PTO lattice. The lattice interstitial confinement was beneficial for the formation of small and highly dispersed Pt In bimetallic species on the surface of γ -Al 2 O 3 supported PTO Nano islands. It is just the confinement of PTO lattice interstitial sites for appropriate In 3+ /In 0 ratio and weak Pt In interaction and the sharing Al O bond for anchoring PTO nanoparticles and weakening the surface acid sites result in the high activity and superior stability of PtIn/LaAlO 3 / γ -Al 2 O 3 in propane dehydrogenation. The initial propane conversion of PtIn/LaAlO 3 / γ -Al 2 O 3 was 47%, and can be maintained at 25% after 16 h, while its propene selectivity only decreased from 96% to 90%.