Pt-xCe nanoparticles confined within HZSM-5 for increasing the selectivity of light olefins in iso-butane cracking

Pt-xCe@HZSM-5-op catalysts with different Ce contents were successfully synthesized via a hydrothermal method to increase the added value of iso-butane. The effects of the introduction of metal into zeolite on the relative crystallinity, pore characteristics, morphology, metal state and acidity were investigated by X-ray diffraction, N₂ adsorption‒desorption, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, temperature-programmed desorption of ammonia and pyridine infrared spectroscopy. The introduction of Pt and Ce species decreased the amounts of weak acid sites and increased the strong acid content of HZSM-5 catalyst. And it also adjusted the distribution of B acid and L acid. Moreover, the effect of varying Ce content was investigated on the catalytic cracking performance of Pt-xCe@HZSM-5-op catalysts. Among the catalysts, Pt-0.25Ce@HZSM-5-op catalyst exhibited the best catalytic performance for iso-butane cracking at 625 °C.