Chelation Ion Exchange Properties of 2, 4‐Dihydroxyacetophenone‐Biuret‐Formaldehyde Terpolymer Resin

The terpolymer resin 2, 4‐HABF has been synthesized by the condensation of 2, 4‐dihydroxyacetophenone (2, 4‐HA) and biuret (B) with formaldehyde (F) in 1:1:2 molar ratios in presence of 2 M hydrochloric acid as catalyst. UV‐Visible, IR and proton NMR spectral studies have been carried out to elucidate the structure of the resin. A terpolymer (2, 4‐HABF) proved to be a selective chelating ion exchange polymer for certain metals. Chelating ion‐exchange properties of this polymer were studied for Fe 3+ , Cu 2+ , Ni 2+ , Co 2+ , Zn 2+ , Cd 2+ and Pb 2+ ions. A batch equilibrium method was employed in the study of the selectivity of metal ion uptake involving the measurement of the distribution of a given metal ion between the polymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in media of various ionic strengths. The polymer showed highest selectivity for Fe 3+ , Cu 2+ ions than for Ni 2+ , Co 2+ , Zn 2+ , Cd 2+ , and Pb 2+ ions. Study of distribution ratio as a formation of pH indicates that the amount of metal ion taken by resin is increases with the increasing pH of the medium.