Issue Description


Authors : M. B. Thakre

Page Nos : 189-211

Description :
Copolymer (4-HBAF) was synthesized by the condensation of 4-hydroxybenzoic acid [4-HB] and adipamide [A] with formaldehyde [F] in the presence of acid catalyst at 127 ºC was proved to be a selective chelating ion-exchange copolymer for certain metals. A copolymer composition has been determined on the basis of their elemental analysis and the number average molecular weight of this copolymer was determined by conductometric titration in non-aqueous medium. The viscosity measurements in dimethyl sulphoxide (DMSO) has been carried out with a view to ascertain the characteristic functions and constants. The newly synthesized copolymer resin was characterized by UV-visible spectra, IR spectra, and 1H NMR spectra. The copolymer has been further characterized by absorption spectra in non-aqueous medium to elucidate the structure. Ion-exchange properties of this resin was studied by batch equilibrium method for Fe3+, Cu 2+, Ni2+, Zn2+, Co2+, Cd2+ and Pb2+ ions over the pH range, 1.5 to 6.5 and in media of various ionic strengths. The resin shows a higher selectivity for Fe3+ ion over any other ions. Study of distribution ratio as a function of pH indicates that the amount of metal ion taken by resin is increases with the increasing pH of medium. The surface morphology of the copolymer resin was examined by scanning electron microscopy and it establishes the transition state between crystalline and amorphous nature.

Date of Online: 30 Sep 2013