Complexing capsules--metal extraction and modeling of ion transfer

Polyamide complexing capsules containing a poly(acrylic acid) gel are synthesized by a two steps polymerization process with various diameters (10 microm for microcaps or 200 microm for mcaps). A cationic exchange between gel carboxylic functions and metal ions is realized. Extraction and stripping measurements show that the composition of the capsule membrane doesn't hinder the mass transfer. A model, taking account only of the diffusion in the gel phase, is studied.