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Effect of acid modification of kaolin and metakaolin on Brønsted acidity and catalytic properties in the synthesis of octahydro-2H-chromen-4-ol from vanillin and isopulegolстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 24 октября 2016 г.
- Авторы: Timofeeva M.N., Panchenko V.N., Volcho K.P., Zakusin S.V., Krupskaya V.V., Gil A., Mikhalchenko O.S., Vicente M.A.
- Журнал: Journal of Molecular Catalysis A: Chemical
- Том: 414
- Год издания: 2016
- Издательство: Elsevier BV
- Местоположение издательства: Netherlands
- Первая страница: 160
- Последняя страница: 166
- DOI: 10.1016/j.molcata.2016.01.010
- Аннотация: Natural kaolin and the metakaolin obtained by calcination of kaolin at 650◦C were chemically activatedusing 0.25–3.0 mol/dm3HCl solutions. Structural and textural properties of samples were characterizedby X-ray diffraction, elemental analysis and N2-adsorption/desorption analyses. The amount of Brønstedacid sites (BAS) was determined by infrared spectroscopy using pyridine as probe molecule. The amountof BAS for kaolin rose with increasing HCl concentration up to 1.0 M, and decreased for higher concen-trations, that is related with the leaching of Al from the solid. Effect of HCl concentration on amountof BAS was negligible for metakaolin. The catalytic performance of these materials was investigated inthe Prins cyclization of (−)-isopulegol with vanillin to form octahydro-2H-chromen-4-ol, carried out intoluene at 50◦C. The reaction rate and the selectivity toward octahydro-2H-chromen-4-ol depended onthe Bronsted acidity, structural and textural properties of the catalysts. The reaction rate in the presenceof kaolin modified by HCl correlated with the amount of BAS. HCl-kaolin samples were more active com-pared with HCl-metakaolin, while selectivity reaction toward octahydro-2H-chromen-4-ol was larger inthe presence of HCl-metakaolin.
- Добавил в систему: Крупская Виктория Валерьевна