Investigation On The Regulation Of Rare Earth Species In REY Zeolites With High Hydrogen Transfer Activity

Faced with the strict requirements of the National VI Standard for reducing the content of oligomers,the development of a new type of catalyst for reducing catalysts and maintaining gasoline octane clean technology will become the focus of future research.Rare earth modified Y zeolites（REY）is the main activity of the catalytic cracking catalysts.Therefore,it is particularly important to systematically explore the replacement mechanism of the rare mechanism of REY zeolites with high hydrogen transfer activity.In this study,cyclohexene was used as a representative of olefin and catalyzed by CeY zeolites in a fixed-bed reactor under mild conditions,and the influence of Ce species in hydride transfer reaction over CeY zeolites have been evaluated.CeY zeolites show excellent hydride transfer properties than that of HY zeolite.Based on the product distribution results of almost the same Br?nsted acid property samples,it was found that the strength and density of the Br?nsted acid are not the decisive factors for the hydrogen transfer reaction.A unique band at 1442 cm^–1 in situ FTIR spectroscopy spectra are assigned to pyridine complexes bonded to a class of active Ce species that could reversibly migrate from the core of SOD cages to its6-rings mouth towards the supercages.These results provide valuable information that these active Ce species should play a synergistic role with the Br?nsted acid sites on enhancing the hydride transfer reaction with a bimolecular mechanism over CeY zeolites.At the same time,this article is to better study the process of hydrogen transfer reaction of cyclohexene on REY zeolites.Through the investigation of the initial kinetic parameters of the reaction products,the effect of rare earth species on the performance of the hydrogen transfer reaction was further analyzed.Studies have shown that the introduction reaction path of Ce species is more inclined to generate cyclohexane,which can significantly improve the performance of hydrogen transfer reaction.