Synthesis and chelation ion exchange properties of 2, 4-dihydroxyacetophenone-biuret-formaldehyde terpolymer resin

531-535The terpolymer resin 2, 4-dihydroxyacetophenone-biuret-formaldehyde has been synthesized by the condensation of 2, 4-dihydroxyacetophenone and biuret with formaldehyde in 2:1:3 molar ratios in presence of 2M hydrochloric acid as catalyst. UV-visible, IR and proton NMR spectral studies have been carried out to elucidate the structure of the resin. The terpolymer has proved to be a selective chelating ion exchange polymer for some metals. Chelating ion exchange properties of this polymer have been studied for Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+ and Pb2+ ions. Batch equilibrium method has been employed to study the selectivity of metal ion uptake and distribution coefficient over a wide pH range and in media of varying ionic strengths. The polymer shows higher selectivity for Fe3+ and Cu2+ ions than for Ni2+, Co2+, Zn2+, Cd2+ and Pb2+ ions. Study of distribution ratio as a function of pH indicates that the amount of metal ion uptake by resin increases with the increasing pH of the medium