Chiral resolution by β-cyclodextrin polymer-impregnated ceramic membranes

In this study, a porous tubular ceramic membrane was impregnated with a beta-cyclodextrin (CD) polymer to obtain a chiral-selective membrane. The membrane was evaluated in terms of the effectiveness of impregnation as well as the ability to separate the enantiomers of the racemic pharmaceutical chlorthalidone (CT). Impregnation into the pores of the ceramic support was shown by the increase in weight and confirmed by porosimetry. In spite of polymer loss from the membrane during the permeation of CT, an average separation factor (alpha) of 1.24 was attained. The proposed mechanism of selectivity permits continual retrieval of both enantiomers in a process similar to the permeation swing adsorption. (C) 2000 Elsevier Science B.V. All rights reserved.