Surface-functionalized mesoporous gallosilicate catalysts for the efficient and sustainable upgrading of glycerol to solketal. Issue 1 (5th November 2020)

• Record Type: Journal Article
• Authors: Vivian, Alvise; Soumoy, Loraine; Fusaro, Luca; Fiorilli, Sonia; Debecker, Damien P.; Aprile, Carmela
• Is Part Of: Green chemistry. Volume 23:Issue 1(2021)
• Page Start: 354
• Page End: 366
• Publication Date: 2020-11-05
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/d0gc02562c
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : Hybrid gallosilicate catalysts prepared in a continuous one-pot procedure are proposed as active and reusable solids in the conversion of glycerol into solketal Abstract : Two series of functionalized mesoporous Ga silicates were prepared in a straightforward and sustainable one-pot procedure using different alkyl silanes. The efficacy of the adopted co-synthetic approach based on aerosol processing has been proved by 29 Si solid-state NMR experiments revealing a degree of functionalization close to the theoretical value. The successful incorporation of gallium as single sites within the silica framework was confirmed via 71 Ga solid-state magic-angle-spinning NMR measurements. These materials were tested as catalysts for the synthesis of solketal from glycerol at low temperature and under solventless conditions. A systematic study evidenced the importance of a careful tuning of surface polarity, achievable with surface functionalization as well as with different thermal treatments. The solids functionalized with a low degree of methyl groups (5%) displayed enhanced performances compared to the non-functionalized analogues, highlighting the highly beneficial role of surface hydrophobicity as well as the importance of the careful tuning of the hydrophilic/hydrophobic balance. The best functionalized catalysts proved to be easily reusable for multiple catalytic runs. With such a high-performance catalyst in hand, we propose a process which shows a favorable E -factor, indicating that the production of solketal can be envisaged in a sustainable way.