Abstract
A new crystalline organic-inorganic composite cation exchanger polyaniline Sn(IV) molybdate was developed by mixing polyaniline into the inorganic precipitate of Sn(IV) molybdate. This material was characterized using Fourier transform infrared spectroscopy (FTIR), simultaneous thermogravimetry-differential thermogravimetry (TGA-DTA), X-ray, scanning electron microscopy (SEM) and elemental analysis studies. Ion-exchange capacity, effect of calcinations (100-500 A degrees C) on ion exchange capacity, pH-titrations, chemical stability, elution and distribution behavior were also carried on this material. On the basis of distribution studies, the material was found to be highly selective for Pb2+ ion and its selectivity was tested by achieving some important binary and ternary separations. In order to demonstrate the practical utility of the material, quantitative separations of Pb2+ from a standard reference material (Rompin Hematite) of lead have been achieved. Thermodynamic parameters viz- entropy change (Delta S), enthalpy change (Delta H) and Gibb's free energy change (Delta G) were also calculated.