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Updated: May 23, 2026
09:31
Surface Properties of Synthesized Nanoporous Carbon and Silica Matrices
Published on: March 27, 2019
L- and D-proline adsorption by chiral ordered mesoporous silica
Clara Casado1, Joaquín Castán, Ismael Gracia
1Department of Chemical and Environmental Engineering and Instituto de Nanociencia de Aragón (INA), ‡Department of Organic Chemistry, and §Laboratorio de Microscopías Avanzadas, INA, Universidad de Zaragoza , 50018 Zaragoza, Spain.
Langmuir : the ACS Journal of Surfaces and Colloids
|April 6, 2012
Summary
Chiral ordered mesoporous silica (COMS) effectively separates L- and D-proline enantiomers. Both calcination and microwave extraction methods produced enantioselective silicas, demonstrating potential for chiral separations.
Area of Science:
- Materials Science
- Nanotechnology
- Chemistry
Background:
- Chiral ordered mesoporous silica (COMS) materials are of interest for enantioselective applications.
- Amino acids like proline are important chiral building blocks and targets for separation.
Purpose of the Study:
- To synthesize chiral ordered mesoporous silica (COMS) using proline as a chiral template.
- To investigate the enantioselective adsorption properties of the synthesized COMS for proline enantiomers.
Main Methods:
- Synthesis of COMS using tetraethyl orthosilicate and quaternized aminosilane in the presence of L- or D-proline.
- Activation of COMS via calcination or microwave chemical extraction to remove organic templates.
- Characterization using powder X-ray diffraction and N2 adsorption.
- Adsorption studies with L- and D-proline enantiomers.
Main Results:
- COMS materials exhibited MCM-41-type structural and textural features.
- L-Pro-COMS showed higher adsorption capacity for L-proline (2.3 mmol/g) than D-proline (0.6 mmol/g).
- D-Pro-COMS demonstrated higher adsorption for D-proline than L-proline.
- Both activation methods yielded enantioselective silicas capable of separating proline racemate.
Conclusions:
- The synthesized COMS materials are enantioselective and can separate proline enantiomers.
- Both calcination and microwave chemical extraction are viable methods for preparing enantioselective COMS.
- These materials show promise for applications in chiral separations.
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