Supported liquid membrane stability in chiral resolution by chemically andphysically modified membranes

In the present work some stability studies on Supported Liquid Membranes (S LMs) to be used for chiral separations were realized. In particular, primar y aim was to determine how a modification of the support surface influences the SLM stability. First, the procedure for support modification was optim ised, making a screening of various compounds (sulphuric acid, nitric acid, chromic acid, sodium dodecyl sulphate (SDS), glycerol, oleic alcohol, prop ylene glycol (PPG), bovine serum albumin (BSA)) and testing their performan ce by means of contact angle measurements. Next, a second screening was rea lized by permeation tests in a stirred cell. Finally, to compare the stabil ity of modified with unmodified support in a process of interest for chemic al and/or biochemical industries, some permeation tests for resolution of D NB-DL-Leucine were realized in a re-circulation system. Results showed a be tter surface hydrophilization of chemically modified support and better sta bility of the sulphonated support. However, in operating conditions a littl e high stability of the unmodified support was obtained.