Wuhan Institute of Mathematics, etc. have made progress in the solvation effect of molecular sieve confined pores
The Deng Feng research group of the State Key Laboratory of Spectroscopy and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, in cooperation with the Liu Shangbin research group of the Taiwan Institute of Atomic and Molecular Sciences, has made progress in the study of the solvation effect in the nano-confined pore channels of zeolite molecular sieve There is a special solvation effect between the same kind of adsorbed molecules in the restricted pore channels of the molecular sieve, thus effectively enhancing the apparent acid strength of the molecular sieve. The results of this study have recently been published in the Royal Chemical Society Journal Chemical Communications (2012, 48, 6936-6938).
Solvation effects are ubiquitous in homogeneous catalysis, and the thermodynamic and kinetic properties of the catalytic reaction can be effectively controlled by choosing a suitable solvent. The nanometer-sized pore structure of zeolite molecular sieve provides a special environment for the transition state of heterogeneous catalytic reactions and the formation and conversion of intermediates. Its catalytic properties are different from traditional liquid homogeneous catalysis. The research group led by Researcher Deng Feng has long been devoted to the development of solid-state NMR methods and the research on the structure and reaction performance of environmentally friendly heterogeneous catalysts. Associate researcher Zheng Anmin and graduate student Han Bing of the research group used solid nuclear magnetic resonance (NMR) probe molecular experiment technology, combined with quantitative calculations, and found that it was restricted to the adsorption of trimethylphosphorus molecules in the pore channel of the mordenite molecular sieve There is an overlap of electron clouds between them, which shows a similar solvation effect, so that the apparent acid strength of the mordenite molecular sieve reaches "super strong acid" (stronger than 100% H2SO4).
The results of this study laid the foundation for further study of the molecular sieve acid catalytic reaction mechanism at the atomic and molecular level.
This project has received strong support from the National Natural Science Foundation of China's key projects (20703058) and general projects (21073228, 20773159).
Structure of Mordenite molecular sieve adsorbing 3 TMPO molecules in the restricted channels
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