Hydrothermal Synthesis of Highly Cross-linked PtZn@Silicalite-1
Structured Catalysts for Propane Dehydrogenation
Abstract
Structured catalysts coatings exhibit excellent performance on
non-adiabatic gas-solid process, deriving from their enhanced heat and
mass transfer properties. However, the coating catalysts prepared by
traditional hydrothermal method of zeolite encapsulating noble metal are
prone to spalling, especially under conditions of large flow rate and
high temperature. Herein, we prepared PtZn clusters encapsulated in
silicalite-1 zeolite coating on stainless steel with high bonding
strength by an improved in-situ growth method. The optimized catalyst
exhibited ultra-thin, uniform, continuous, and high degree of
crosslinking, thereby enhancing mass transfer and thermal stability. In
propane dehydrogenation reaction (PDH), the optimized PtZn@S-1-R showed
a high specific activity of 14.7 molC3H6·molPt-1·s-1 and a propylene
selectivity above 99% at 600 °C with a high weight hourly space
velocity (WHSV) of 120 h-1. The metal-encapsulated zeolite coating
catalysts open up a new avenue for heterogeneous catalysis with great
application prospects.