Patent ID: 7214321

Claim:
A method for testing the appropriateness of a cation-exchanger for removing a substance from a liquid, said method comprising the steps: (a) providing a library which comprises (i) one or more cation-exchangers to be tested (exchangers 1, 2, 3, 4 . . . n; n=an integer>0) each of which cation-exchangers differs with respect to kind of ligand (ligands 1, 2, 3, 4 . . . n), and (ii) one or more reference cation-exchangers having reference ligands, wherein the support matrix and the substitution degree are essentially the same in the exchangers 1, 2, 3, 4 . . . n and in the reference cation-exchanger; (b) determining the breakthrough capacity of exchanger 1 for the substance at predetermined conditions; (c) determining the breakthrough capacity of the reference cation-exchanger for the substance at the same conditions as in step (b); (d) concluding from the relation between the breakthrough capacities obtained in steps (b) and (c), if cation-exchanger 1 is appropriate to use for removing the substance; and (e) repeating steps (b), (c) and (d) for at least one of the exchangers 2, 3, 4 . . . n.