Abstract: A process of separating one or more seleced species of ions from a solution containing the ions comprises contacting the solution with a novel composition of matter comprising a hydrocarbon chain covalently bonded to a macrocyclic compound, wherein the macrocyclic compound has at least four --A--C--C-- linkages in which A for each such linkage, is independently selected from the group consisting of O, O--CH.sub.2, S, SH.sub.2, NR, and NRCH.sub.2, with R being independently selected from the group consisting of hydrogen, alkyl and benzyl, and wherein the hydrocarbon chain has an end group ##STR1## with X being independently selected from the group consisting of lower alkyl, benzyl, phenyl, halogen, O--CH.sub.3, O--C.sub.2 H.sub.5 and O-matrix, and with matrix being independently selected from the group consisting of silica, silica gel, glass, glass fibers, titania, zirconia, alumina and nickle oxide.

Abstract: The invention is a process of selectively and quantitatively removing and concentrating at least one selected ion prosent in low concentration with other ions in higher concentration in a multiple ion solution. The method comprises bringing a complexing agent for the selected ion(s) into contact with a different determined quantity of said multiple ion solution to remove and concentrate the selected ion(s) from the multiple ion solution; removing the multiple ion solution, from which the complexing agent has been removed, the selected ions from the complexing agent having the selected ion(s) complexed therewith, bringing the complexing agent complexed with selected ion(s) into contact with a determined quantity of receiving liquid to break the complex and remove the selected and concentrated ion(s) from the complexing agent therein, and determining the concentration of selected ion(s) in said receiving liquid from which the concentration of selected ion(s) in the multiple ion solution can be calculated.

Abstract: The invention relates to a composition of matter comprising compounds selected from the class consisting of ##STR1## and ##STR2## This process can be carried out in these ways: (A) as ligands in a liquid membrane phase for selectively; and competitively separating desired metal ions from mixtures with other ions in a separate source phase and transporting these ions to a separate receiving phase, with both of which the liquid membrane phase is in interfacial contact long enough to effect substantial removal of the desired ions from the source phase and transporting them to the receiving phase from which they are recovered, (B) as covalently bonded to silica gel supported in a column through which the multiple ion solution is first flowed, followed by receiving liquid, and (C) as ligand in an organic liquid filling pores or apertures in the wall of a hollow fiber in a bundle of hollow fibers on opposite sides of which flow the multiple ion solution and the receiving liquid.