Properties of chelating sorbents prepared by modification of LiChroprep RP-8 and LiChroprep RP-18 with calconecarboxylic acid

Two new chelating sorbents for metal ions were prepared by the impregnation of chemically modified silicas LiChroprep RP-8 and RP-18 with ion pairs composed of the cation of Aliquat 336 and the anion of Calconecarboxylic Acid (CCA). The sorbents were compared with an analogous sorbent with a plain silica carrier containing the same ion pairs. A hypothetical molecular mechanism of binding this ion pair by the surfaces of the applied carriers was presented. A higher stability of the two sorbents in comparison with that of the plain silica chelating sorbent was demonstrated. The sorbents obtained were applied for chromatographic separations of some chosen mixtures of some metal ions and for additional purification of aqueous solutions of alkali metals from trace amounts of heavy metals. The multiple use of the sorbents based on RP-8 and RP-18 in sorption-desorption processes of metal ions without deterioration of their sorption capacities was demonstrated.