A novel insight into enhanced propane combustion performance on PtUSY catalyst

Platinum was supported on gamma-Al2O3 and ultra-stable Y zeolite (USY) by an incipient wetness impregnation method. The catalysts were characterized by nitrogen physisorption, transmission electron microscopy (TEM), CO/C3H8 isothermal oxidations, NH3 temperature-programmed desorption (NH3-TPD) and infrared (IR) spectroscopy of adsorbed probe molecules (CO, C3H8 and C3H8 + O-2). Compared with Pt/Al2O3, PtUSY catalyst shows obviously higher activity for the combustion of propane. After estimating the size effect of Pt particles and propane adsorption capacity of USY, the excellent activity of PtUSY is also attributed to the strong interactions between the precious metal and the acidic zeolite. It inhibits the oxidation of Pt in an oxygen-rich atmosphere at high temperatures, which facilitate the initial oxidation step involving the C-H bond activation on metallic Pt as reflected by in situ diffuse reflectance infrared Fourier-transformed (DRIFT) spectra.