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Information × Registration Number 0223U000031, 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 01-01-2023 Organization L. V. Pisarzhevskii Institute Of Physical Chemistry of The National Academy of Sciences of Ukraine popup.description2  In the work, a set of Al-, Sn-, Zr-containing hierarchical zeolites, mesoporous molecular sieves and hydrotalcites were obtained. It was shown for the first time that AlZr-BEA and AlSn-BEA are characterized by high activity in the oxidation of cyclohexanone with hydrogen peroxide, the conversion of which reaches 80% (6 hours, 80 ⁰C) for the sample ZrAl-BEA-4-75/20 (selectivity with respect to of ε-caprolactone is 80%). A high selectivity of ZrAl-BEA and SnAl-BEA catalysts was revealed when conducting a catalytic experiment at a temperature of 80 ⁰C, while increasing its temperature to 90 ⁰C and 100 ⁰C leads to almost complete conversion of the target ε-caprolactone into 6-hydroxycaproic acid. It was found that as the concentration of Lewis acid centers increases in the specified Si/Sn range for mesoporous Sn-BEA, the conversion of cyclohexanone and cyclopentanone increases, reaching values of 70.5% and 35%, respectively, with a selectivity to the target lactone of more than 99% (6 hours, 90 ⁰С). For Sn-BEA samples obtained by post-synthetic modification of hierarchical zeolites, it is shown that the highest yields of lactones in the oxidation reaction of cyclic ketones (cyclohexanone and D-dihydrocarvone) with hydrogen peroxide are achieved under the condition of using Sn-Beta with Si/Sn=13. It is shown that catalysts based on Mg-Al-Zr hydrotalcites and oxides are promising catalysts for use in the oxidation of cyclohexanone with hydrogen peroxide ("green" oxidizer) under mild conditions (100 ⁰С, atmospheric pressure), and the highest yield was achieved for the sample Mg-Al-Zr-3 (Mg/Al=3) Product Description popup.authors Barakov Roman Yuryevich Valihura Karina V Kurmach Mykhailo M. popup.nrat_date 2023-01-01 Close