Salting out of elements Mg and Ca by clay in physiological gastro-intestinal mediums physicochemically simulated

Edible clays from West Africa (Sénégal, Côte d’Ivoire, Guinée) are characterized by XRD, IR, TGA and ICP. The major component is kaolinite and silica is the main impurity while illite is found in some of them. Kinetic analysis of salting out of Ca2+ and Mg2+ were studied by Ionic Chromatography in physicochemically simulated physiological mediums (SPM). Raw and heated (110 °C) materials have been studied. Cations releasing from both materials was higher for Ca2+ than Mg2+. Stomachal SPM (1 < pH < 2) is the most favourable to this behaviour. Cations exchange is the most probable process involving Na+ (0.102 nm) (SPM) and Ca2+ (0.100 nm), Mg2+ (0.072 nm) (Clay).