Dalian Institute of Chemical Physics Cryogenic molecular sieve acid-base catalysis and synthesis of fine chemicals innovative SAR Research Group Huang Shengjun team in the controllable properties of silicon aluminum molecular sieve adjustment, the first time to achieve the 'dealumination' - 'silicon removal' bridge process.
Molecular sieve has been widely used in modern petroleum refining and chemical industry.Adjusting the properties of molecular sieve such as acidity and pore structure is a hot issue in the field of molecular sieve catalysis application. And structural units, to adjust the center of aluminum, the technology has more than half a century of research and development history, the representative method - steam treatment is widely used in the industrial production of aluminosilicate molecular sieve catalyst, but the 'dealumination' There are some limitations in adjusting the properties of silica-alumina molecular sieve at the micro-pore scale.In recent years, the gradual rise of the silicon-free post-treatment method that adjusts the silicon center can adjust the molecular sieve properties Since this method is subject to the existing aluminum content and particle size of the aluminosilicate molecular sieve, its range of application is also limited.
For the first time, this study by Huang Shengjun team successfully bridged the 'de-alumination' and 'desiliconization' methods. By combining the simple and easy-to-implement water vapor treatment with alkali treatment, the double high molecular weight and large particle size Limited and successfully constructed concentrated and controlled microporous-mesoporous multistage pore structure in the MFI molecular sieve with high content of aluminum, and maintained abundant strong acid sites and good hydrothermal stability. This study has broken the common at home and abroad Following the non-bridgeable limitations of 'dealumination' and 'desilication', it provides a richer 'toolbox' for the development of low cost, convenient and scalable industrial catalyst preparation methods, The structure, position and skeleton interaction of non-framework Al species play an important role in the modulation of molecular sieve properties, which brings a new perspective to the traditional classic research of Si-Al molecular sieve.
Relevant research results published in the "German Applied Chemistry." The study was funded by the National Natural Science Foundation.
