Vapor phase condensation of ethyl lactate into lactide over SnO2/SiO2 catalyst

Varvarin, AM, Levytska, SI, 1Brei, VV
1Institute for Sorption and Problems of Endoecology of the NAS of Ukraine, Kyiv
Dopov. Nac. akad. nauk Ukr. 2018, 1:73-79
Section: Chemistry
Language: Ukrainian

The vapor phase conversion of 20 % solutions of ethyl lactate in cyclohexane into lactide over various oxides with the supported phase of SnO2 is investigated in the continuous regime at 200—260 °C. It was found that SnO2/SiO2 catalyst provides 40 % conversion of ethyl lactate with 44 % selectivity toward lactide at 250 °C. A scheme of lactide formation from ethyl lactate with the participation of L-acid sites of the SnO2 surface is discussed.

Keywords: ethyl lactate, lactide, supported catalyst, tin dioxide, vapor phase conversion
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