Copper-Promoted Platinum Supported on HSSZ-13 Zeolite Catalysts for Propane Dehydrogenation to Propylene

Abstract

Pt/HSSZ-13 with 0.5−3 wt % Pt load and PtCu/ HSSZ-13 with 1−7 wt % Cu load were prepared by the initial wetness impregnation method. Without compromising the original crystal structure and surface texture characteristics, doped Pt and Cu are dispersed uniformly throughout the surface. The Si/Al molar ratio affected not only the texture of the crystal but also the number of acid sites on the catalyst surface. The appropriate addition of Cu significantly increased the dispersion of Pt. The addition of Cu also provided electrons to Pt, affected the electron cloud density on the surface of Pt, and then reduced the adsorption of propylene and improved the selectivity of propylene. Cu can also decrease the number of acidic sites on the catalyst surface, thus slowing the deactivation rate of the catalyst and the amount of carbon deposition during the reaction. 1.0Pt3.0Cu/HSSZ-13(40) had a small number of strong acid sites (3.89 μmol/g) and showed the best propane initial conversion (73.95%), excellent propylene selectivity (97.60%), lowest deactivation constant (0.33 h −1 ), and good regeneration robustness.