Online monitoring of preferential crystallization of enantiomers
Abstract
Polarimetry is used for continuous online monitoring of optical resolution by preferential crystallization. In combination with refractometry the liquid phase composition is determined, allowing one to follow the resolution progress quantitatively. The measurement techniques were calibrated up to relatively high solution concentrations and combined with the crystallizer. The resolution of DL‐threonine was performed by preferential crystallization experiments in aqueous solution varying several process parameters like supersaturation, seed amount, initial enantiomeric excess, and scale. The resolution progress can be conveniently described by profiles of the optical rotation (polarimetric signal) and the crystallization pathway in the corresponding ternary phase diagram. The method outlined is applicable for dynamic process optimization and control purposes in “quasi‐continuous” chiral separation processes. Chirality 16:499–508, 2004.Keywords
This publication has 8 references indexed in Scilit:
- Solubility Equilibria in Chiral Systems and Their Importance for EnantioseparationEngineering in Life Sciences, 2003
- Enantiomeric Mandelic Acid SystemMelting Point Phase Diagram and Solubility in WaterJournal of Chemical & Engineering Data, 2002
- Investigations on the reciprocal ternary system (±)-2-phenylpropionic acid–(±)-α-methylbenzylamine. Impact of an unstable racemic compound on the simultaneous resolution of chiral acids and bases by preferential crystallisationJournal of the Chemical Society, Perkin Transactions 2, 2001
- Preferential crystallisation and comparative crystal growth study between pure enantiomer and racemic mixture of a chiral molecule: 5-ethyl-5-methylhydantoinChemical Engineering Science, 2001
- Processes and phenomena of purity decrease during the optical resolution of dl-threonine by preferential crystallizationColloids and Surfaces A: Physicochemical and Engineering Aspects, 2000
- Kinetics of chiral resolution in stirred crystallization of D/L-glutamic acidChirality, 1999
- Determination of enantiomeric excess using a chiral selective separation mode and polarimetric detectionTalanta, 1997
- Purity Decrease of L-Threonine Crystals in Optical Resolution by Batch Preferential Crystallization1990