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Highlights: [•] Asymmetric chiral Ru(II) complexes were encapsulated in zeolite MY. [•] The complex encapsulated in LiY has higher ee selectivity than the homogenous. [•] The alkali metal cation exchanged Y has different host effect to the complex. [•] The reactivity was supported by DFT calculation and UV–vis spectra ananlysis. [Copyright &y& Elsevier]

Abstract: Y-Beta zeolite composites denoted as HS-FBZ (High-Silica-Faujasite-Beta-Zeolite) were synthesized hydrothermally using high silica Y as precursor and characterized by XRD, N2 adsorption, SEM, HRTEM, NH3-TPD and FT-IR spectra of pyridine. The results reveal that the different ratios of Y and Beta zeolites in the composites induced the change of surface areas, pore diameters and acid properties of HS-FBZ, and the extended Beta layers on the zeolite Y surface were observed. The composite exhibited an excellent hydrocracking activity for heavy oil. Compared with the corresponding physical mixture of Y and Beta zeolites, the zeolite composite as a hydrocracking catalyst for vacuum gas oil increased the heavy naphtha yield by 5.61wt% and the jet fuel yield by 11.52wt%. [Copyright &y& Elsevier]

A microspherical mesostructured zeolite (MMZ-5) with MFI-topological frameworks is employed. In-situ FT-IR spectra of pyridine and 2, 6-di-tert-butylpyridine have indicated that almost all of the acid sites are located on the zeolitic external surface, which are favorable for access of reactive large molecules. This key effect, along with the reduced diffusion and steric limitation, has been proposed to be main the reason for the enhanced catalytic activity, selectivity and stability exhibited in benzylation of aromatics with benzyl chloride. The need for optimized characterization of the mesoporous surface acidity for different aromatics is highlighted. [ABSTRACT FROM AUTHOR]