Organosilane-directed synthesis of Ge-modified Pt species in silicalite-1 zeolite for propane dehydrogenation

Propane dehydrogenation (PDH) provides an enormous potential strategy to narrow the gap between the provision and the requirement of propene, but maintaining the stability of Pt-based catalysts in the reactions of high temperatures and pure propane stream usually creates great challenges because of the sintering of the catalysts and the coke formation. Here, we design an original catalyst with Ge-stabilized Pt species in organosilanedirected silicalite-1 (S-1) zeolite for efficient and stable propane dehydrogenation. The catalyst offered a propane conversion over 35.4 % with the propene selectivity increasing from 95.9 % to 97.6 % at 580 degrees C with the weight hourly space velocity (WHSV) of 10.8 h- 1 after 50 h of reaction under pure propane stream over the 0.5Pt2GeK@S-1-TPOAC catalyst, and the propylene spacetime yield reached up to 59.1 mol g-1Pth-1. No obvious deactivation and no apparent sintering of particles were observed over 0.5Pt2GeK@S-1-TPOAC catalyst after 50 h on pure propane stream. Based on TPD, in situ FTIR, TG, et al. characterization, we reveal that the excellent stability and propene selectivity are ascribed to the modification of Ge species and the introduction of the organosilane, which strengthened the electron transfer to boost the stability and regulated the acid sites of the catalysts to enhance the selectivity of propene, respectively.