Synthesis, Characterization And Catalytic Behavior Of Novel Amphiphilic βZeolite

β zeolite is a high-silica zeolite with large-pore three-dimensional structure, it was used in the petrochemical and fine chemical as the acommonly used catalyst support or catalyst because of its acid resistance and anti-coking, showing the catalytic efficiency and good selectivity.Metal atoms in conventional transition metal oxides showed aggregation, however, the metal atoms which were introduced in β zeolites were dispersed in different locations of zeolite framework to increase them catalytic performance, oxidation reduction and others, become a good bifunctional catalyst and other functional materials with specific properties.Most organic reaction systems involved in the two-phase of water and oil, required a large number of solvents to mix evenly to promote the reaction by using ordinary catalysts. Amphiphilic β zeolite as a green catalytic material with lipophilic and hydrophilic can catalyze the interfacial reaction effectively.V-Ni-β and V-Co-P zeolites were synthesized by using hydrothermal method, explored the impact factors of the synthesis, and investigated their catalytic properties. In addition, amphiphilic zeolite catalysts were prepared by using trimethyl chlorosilane modified these two parent zeolites, and examined their catalytic properties in the interfacial reaction. The main contents discussed were as follows:(1) Synthesis, Characterization and Catalytic Behavior of V-Ni-β ZeoliteV-Ni-β zeolite was hydrothermally synthesized in a SiO2-NiO-V2O5-(TEA)2O-H2O-NH4F system. The structure and chemical composition of the products were determined by X-ray diffraction, infrared spectroscopy, UV-Vis diffuse reflection spectroscopy, thermogravimetry-differential thermal analysis, and scanning electron microscopy. The factors affecting the synthesis of V-Ni-P zeolite were investigated. The results indicate that the well-crystallized V-Ni-β zeolite can be synthesized from the precursor with the SiO2:NiO:V2O5:(TEA)2O:H2O:NH4F molar ratio of60:(0.25～4.0):(0.125～2.0):(16～18):(500～650):(30～40), and the V and Ni atoms present in the framework of the zeolite. The as-synthesized V-Ni-β zeolite shows excellent catalytic activity in the oxidation of styrene using H2O2as the oxidant. The styrene conversion was63.7%, the selectivity for benzaldehyde was80.2%.(2) Synthesis and Characterization of V-Co-β ZeoliteV-Co-β zeolite was hydrothermally synthesized by silica as silica source, tetraethyl ammonium hydroxide as template, ammonium fluoride as mineralizer, cobalt chloride and ammonium metavanadate as heteroatoms V and Co source. The structure and chemical composition of the zeolite samples were characterized. The factors that affected the synthesis of V-Co-β zeolite were investigated. The results indicate that the well-crystallized V-Co-β zeolite can be synthesized from the precursor with SiO2:CoO:V2O5:(TEA)2O:H2O:NH4F molar ratio of60:(0.5-3.0):(0.25～1.5):(16～18):(550～650):(25～35), and the V and Co atoms entered the framework of the zeolite.(3) Preparation, Characterization and Catalytic Behavior of Amphiphilic β zeoliteAmphiphilic zeolites(TMS-V-Co-β,TMS-V-Ni-β) were prepared by using TMS to modified parent β zeolite. the samples were characterized The results indicate that the structure of amphiphilic zeolites were not destroyed, the changes of crystal surface is very small. TMS-V-Co-β and TMS-V-Ni-β showed a better catalytic activity than their parent zeolite in cyclohexene hydration.This study can provide new ideas and techniques for the directed synthesis of more active site of the zeolite catalyst to meet the needs of particular reaction. Amphiphilic zeolite can improve the reaction efficiency of multi-phase reaction, has important scientific significance and practical value.