Expansion of new molecular sieve application areas

With the continuous deepening and expansion of molecular sieve research, it has been found that some molecular sieves have new applications in the field of green environmental protection such as gas separation, selective oxidation and selective catalytic reduction (SCR) removal. ETS-4 is a titanium alloy discovered by Kuznick in 1989. Silicon molecular sieve, the framework of which is composed of tetrahedral-coordinated silicon atoms and octahedral-coordinated titanium atoms. After research, it was found that the dehydration process of ETS-4 molecular sieves can cause systematic, uniform and controllable pore size shrinkage , this phenomenon is called "molecular gate effect", Engelhard company has used this special property of ETS-4 molecular sieve in natural gas pipeline transportation to separate and remove N2 and CO2 impurities in natural gas. In addition , Titanium-silicon molecular sieves with selective oxidation catalytic function, such as TS-1, TS-2 and Ti-MWW, etc., have been used to catalyze H2O2 oxidation of phenol to hydroquinone, ammoxidation of cyclohexanone to cyclohexanone oxime and Propylene epoxidation and other processes have realized the greening of these reaction processes. In the past 20 years, people have mainly focused on the exploration of new types of titanium-silicon molecular sieves (such as Ti-beta, Ti-ZSM-12, Ti-ZSM-48, Ti- mordenite, Ti-SSZ-33, Ti-ITQ-7, Ti-MCM-22 (Ti-MWW) and Ti-MCM-56, how to increase the content of four-coordinated titanium in molecular sieve framework, and new applications of titanium-silicon molecular sieves Sinopec Petrochemical Research Institute and East China Normal University have also carried out a lot of work on the synthesis and industrial application of new titanium-silicon molecular sieves such as hollow titanium-silicon molecular sieves and Ti-MWW. In addition, zeolite molecular sieves have potential application and development value in the fields of environmental protection and other fields as efficient catalysts. For example, how to reduce and eliminate NOx in lean-burn engine and diesel engine exhaust gas with high selectivity is the world's Molecular sieve catalysts containing transition metal ions such as Cu, Fe and V, such as Cu/SAPO-34, Cu/Beta or Fe/Beta and Cu/ZSM-5, have high catalytic activity for SCR reaction, With good selectivity, it has become a hot spot in the field of molecular sieve catalysis in recent years. We also expect more new applications of molecular sieves.