A new type of catalyst containing magnesium oxide modified with various modifiers ranging from bromine and iodine, to interhalogen compounds, hydrohalogenic acids, and alkyl halides have been prepared using chemical vapor deposition (CVD) and wet impregnation methods.
The obtained systems were characterized using a number of methods: determination of the concentration of X− ions, surface area determination, powder X‑ray diffraction (PXRD), surface acid – base strength measurements, TPD of probe molecules (acetonitrile, pivalonitrile, triethylamine, and n‑butylamine), TPD-MS of reaction products of methyl iodide with MgO, and Fourier transform infrared spectroscopy (FTIR).
The catalysts’ activity and chemoselectivity during transfer hydrogenation from ethanol to acrolein to allyl alcohol was measured.
A significant increase in the activity of modified MgO (up to 80% conversion) in the transfer hydrogenation of acrolein was found, while maintaining high chemoselectivity (>90%) to allyl alcohol.
As a general conclusion, it was shown that the modification of MgO results in the suppression of strong basic sites of the oxide, with a simultaneous appearance of Brønsted acidic sites on its surface.
Independently, extensive research on the reaction progress of thirty alkyl halides with MgO was also performed in order to determine its ability to neutralize chlorinated wastes.
by Marek Gliński, Urszula Ulkowska, Zbigniew Kaszkur, Dariusz Łomot, Piotr Winiarek. Molecules 2024, 29(13), 3180.
DOI: 10.3390/molecules29133180
First published: 3 July 2024
Article link (OPEN ACCESS!):
https://doi.org/10.3390/molecules29133180
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