Ion-exchange properties of 8-hydroxyquinoline-biuret-formaldehyde tercopolymers

Abstract

Tercopolymer (8-HQBF) prepared by condensation of 8-hydroxyquinoline (8-HQ) and biuret (B) with formaldehyde (F) in the presence of 2<i>M </i>HCl as catalyst was proved to be a selective

chelating ion-exchange tercopolymer for certain metals. Chelating ion-exchange properties of this tercopolymers are studied for Fe³⁺, Cu²⁺, Ni²⁺, Co²⁺, Zn²⁺,<i> </i>Cd²⁺ and Pb²⁺ ions. A batch equilibrium method has been employed in the study of the selectivity of metal ion uptake involving the measurements of the distribution of a given metal ion between the polymer sample and a solution containing the metal ion. The study has been carried out over a wide <i>p</i>H range and in media of various ionic strengths. The polymer shows a higher selectivity for Fe³⁺, Cu²⁺ and Ni²⁺ ions than for Co²⁺, Zn²⁺,<i> </i>Cd²⁺ and Pb²⁺ ions.