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Information × Registration Number 0224U001663, 0122U002381 , R & D reports Title New element-containing zeolites and their analogues for environmentally friendly catalytic processes for the production of cyclic epoxides and lactones popup.stage_title Head Kurmach Mykhailo M., Кандидат хімічних наук Registration Date 26-01-2024 Organization L. V. Pisarzhevskii Institute Of Physical Chemistry of The National Academy of Sciences of Ukraine popup.description2 Synthesis conditions for obtaining titanosilicate zeolites of MFI, BEA, MTW, were optimized. For the first time, hierarchical titanosilicate zeolites of the BEA structural type were obtained using a bifunctional template. The materials are characterized by a high concentration of strong Lewis acid centers, which increases synergistically with the growth of the titanium content in the reaction mixture (in the range from 300 to 33). It was found that in the process of cyclohexene oxidation with hydrogen peroxide, the catalytic activity of BEA titanosilicate zeolites increases with increase in titanium content in the range of 0.5 to 3 mole. %, reaching the maximum values for the sample with a content of 1.5 mol. %. It was found that such materials are characterized by significantly higher activity in the process of cyclooctene epoxidation cyclooctene with hydrogen peroxide in comparison with "microporous" analogues obtained with the same molar content of titanium. Methods of post-synthetic introduction of Ti4+ cations into the crystal lattice of micro-mesoporous zeolites have been developed. It was determined that the selectivity in relation to cyclohexene epoxide in each series of samples decreases in the following series "traditional" > hierarchical "nanoparticles" > hierarchical "nanolayers". During the epoxidation of cyclooctene, the highest yield of corresponding epoxide was achieved at 78% in 24 hours, which significantly exceeds the values obtained for analogues published in the literature. It was shown for the first time that cesium forms of alumino-titanosilicate zeolites of the structural type BEA and titanium-containing talcites can be characterized by high catalytic activity in the process of epoxidation of styrene with tert-butyl alcohol peroxide to the corresponding epoxide at relatively high temperatures of the catalytic experiment. Product Description popup.authors Kurmach Mykhailo M. Pariiska Olena O. Romanovska Natalia I. popup.nrat_date 2024-01-26 Close