Design Synthesis And Catalytic Properties Of Porous Titanium Silicalite Molecular Sieves

As a typical representative of porous catalytic materials,microporous zeolite has been an important industrial catalyst in the field of petrochemical and fine chemicals production.However,the small pore size?1nm?of microporous zeolite makes it less active in the catalytic reaction with larger size,which limits the application of microporous zeolite to a great extent.The appearance of multi pore zeolite catalytic materials has fundamentally overcome the limitation of the small size of microporous zeolites.Multi pore zeolite is a kind of new zeolite catalytic materials with hierarchical pore structure,its special hierarchical structure?microporous and mesoporous and microporous and macroporous?makes the reactant molecule diffusion and mass transfer in the channel has increased significantly,access channel and active center of the reactants is greatly improved,resulting in the conversion efficiency of catalytic reaction to improve.This paper adopts one pot method and two step synthesis method was successfully hierarchicalporous TS-1 titanium silicon molecular sieve was prepared.XRD,FT-IR,UV-Vis,SEM,n₂ adsorption,ICP-MS of hierarchical porous titanium silicon molecular sieve were characterized by means of the hierarchical porous material crystal structure,Ti framework the species and coordination of hierarchical pore size.The catalytic activity of TS-1 zeolite prepared by the reaction of Phenol Hydroxylation with benzaldehyde in one pot reaction was investigated.The catalytic activity of TS-1 zeolite prepared by the reaction of Phenol Hydroxylation with benzaldehyde in one pot reaction was investigated.The results show that the material has a typical MFI structure,and the titanium species are fixed in the framework of four coordination.In the two step synthesis method,the preparation of porous titanium silicon ball amorphous,then TPAOH microporous template agent and alkali source,through the method of high temperature crystallization preparation of multistage mesoporous molecular sieve TS-1 HP-TS-1-B,titanium species four coordination structure and framework of the same material with MFI in.The above two methods can obtain the multi hole TS-1 molecular sieve.In the phenol hydroxylation process of hydroxylation reaction,two kinds of multi pore TS-1molecular sieves HP-TS-1-A and HP-TS-1-B were given a higher conversion rate of phenol was20.9%and 15.9%,respectively,indicating that it has the ability to highlight the catalytic oxidation.It is worth noting that,compared with highly active catalyst TS-1 nanoparticles and generally recognized,HP-TS-1-A and HP-TS-1-B gave higher catalytic efficiency?TOF?,shows that the multi pore structure in the reaction,which is two times larger for the reactants in the hole in the channels of mass transfer and diffusion.It is worth noting that,compared with highly active catalyst TS-1nanoparticles and generally recognized,HP-TS-1-A and HP-TS-1-B gave higher catalytic efficiency?TOF?,shows that the multi pore structure in the reaction,which is two times larger for the reactants in the hole in the channels of mass transfer and diffusion.