The Preparation And Mechanism Study Of Composite Molecular Sieve

The discovery of the mesoporous M41S materials MCM-41, MCM-48 and MCM-50 in 1992 has attracted considerable attention. Consequently, the use of M41S materials has dramatically widened the range of materials available for applications in selective adsorption, seperation, catalytic due to their pore structure and large surface area. Mesoporous molecular sieves (MMS) have uniform and tunable pore size, ordered pore arrays, large ratio surface areas and large pore volumes and have their advantage:functionality and structure, thereby offering considerable potential for wide use incatalysis, separation, nano-optieal apparatus and chromatogram carrier. However, because of the surface of mesoporous materials, they have low hydrothermal stability. Microporous materials have high hydrothermal stability, due to its orderly hole wall structure, so this paper uses microporous structure unit assembly mesoporous wall, mesoporous duct in MCM-48/ZSM-5 composite molecular sieve. And this structure enhances the composite's hydrothermal stability.Based on previous study of composite materials, this paper synthesizes composite under various conditions. Through a series of tests, composites mechanism is also discussed. MCM-48/ZSM-5 composite molecular mechanism is:first synthesis microporous primary and secondary structure unit grain, in the second crystallization and assembed mesoporous template, assemble composite materials.With catalyzing, MMS can be used as catalyst carrier in order to enhance efficiency of catalyst. So we import copper ions in composite. Through the post processing and in-situ synthesis we successful import copper ions into molecular sieve.