Acid Activation of Montmorillonite as a Way of Controlling Its Catalytic Behavior in the Synthesis of Solketal from Glycerol and Acetone

• Published in: Catalysis in industry Vol. 14; no. 2; pp. 208 - 217
• Main Authors: Kovalenko, O. N., Simentsova, I. I., Panchenko, V. N., Timofeeva, M. N.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-06-2022; Springer Nature B.V
• Subjects: Acetone; Catalysis; Catalysis in Chemical and Petrochemical Industry; Chemical synthesis; Chemistry; Chemistry and Materials Science; Glycerol; Montmorillonite; Selectivity; Sulfuric acid; montmorillonite; acetone; solketal; glycerol; acidic activation; cyclocondensation
• ISSN: 2070-0504; 2070-0555
• DOI: 10.1134/S2070050422020040

The effect of acid activation with 0.125–0.5 M Н
2
SO
4
, HCl, and HNO
3
on the physicochemical properties and catalytic performance of natural clay (the Mukhartalinskii deposit) containing 95% montmorillonite (MM) was investigated in the synthesis of solketal [(2,2-dimethyl 1,3-dioxolan-4-yl)methanol] from glycerol and acetone. The reaction rate and selectivity toward solketal are shown to depend on the type and concentration of acid. Both the yield of solketal and the reaction rate rose with increasing acid concentration, which correlates with the increase in the number of Brønsted acid sites. The efficiency of the system was found to diminish in the order MM/HCl > MM/HNO
3
> MM/H
2
SO
4
as the surface acidity decreased.