Issue 5, 2019

Preparation of catalytic deep eutectic solvent-based silica microreactors using a non-aqueous sol–gel route

Abstract

This study describes the microencapsulation of deep eutectic solvents (DESs) via a non-aqueous sol–gel technique. The microencapsulation was performed using oil in oil emulsions as templates for the interfacial polycondensation of silane monomers such as tetraethoxyorthosilicate and polydimethoxysiloxane. The non-aqueous polycondensation of the silane monomers was achieved using formic acid, which acted as both a catalyst and a reagent. The process also required the presence of cetyl polyethyleneglycol/polypropyleneglycol-10/1 dimethicone as an emulsifier to stabilize the emulsion droplets. The silica-enclosed compounds were separated by centrifugation and dried to provide powders that were much easier to handle compared to the original, highly viscous DES bulks. These microcapsules were then used as hosts for palladium nanoparticles and applied in the hydrogenation of different unsaturated compounds. In addition, microcapsules containing choline chloride:L-tartaric acid (1 : 0.5) were used as heterogeneous Brønsted acidic catalysts for the preparation of N-substituted pyrroles. In both cases, the capsules were recycled several times without significant decrease in conversion. This work demonstrates: (1) the efficiency of combining O/O emulsions and formic acid-mediated non-aqueous sol–gel as a technique for microencapsulation, and (2) the benefits of using microencapsulated DESs as heterogeneous catalysts.

Graphical abstract: Preparation of catalytic deep eutectic solvent-based silica microreactors using a non-aqueous sol–gel route

Supplementary files

Article information

Article type
Paper
Submitted
16 Sep 2018
Accepted
06 Jan 2019
First published
07 Jan 2019

J. Mater. Chem. A, 2019,7, 2242-2252

Preparation of catalytic deep eutectic solvent-based silica microreactors using a non-aqueous sol–gel route

C. Batarseh, A. Levi-Zada and R. Abu-Reziq, J. Mater. Chem. A, 2019, 7, 2242 DOI: 10.1039/C8TA09021A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements