WATER-SOLUBLE QUINOLIN-8-OL POLYMER FOR LIQUID-PHASE SEPARATION OF ELEMENTS

The separation of various elements by a water-soluble quinolin-8-ol polymer in conjunction with membrane filtration is demonstrated. The method is based on the retention of inorganic ions by a quinolin-8-ol derivative of poly(ethyleneimine) in a membrane filtration cell and subsequent separation of low-molecular-weight species from the polymer complex formed. It is shown that poly(ethyleneimine) and the polymeric quinolin-8-ol derivative can retain metal ions in aqueous solution. The polymer, however, exhibits a much higher retention capability in acidic solution with respect to more highly charged metal ions, such as Zr, Nb, W, Bi, and can therefore be used for separating them from ions that do not form stable quinolinolates. At higher pH, the water-soluble quinolin-8-ol polymer can be applied to the separation and preconcentration of many metal ions. Owing to the hydrophilic nature of the polymer complex in solution, the preseparated elements remain in the aqueous phase, which is convenient for their subsequent determination by AAS, ICP-AES, etc. © 1990.