International Journal of Modern Science and Technology


​​​​​​​International Journal of Modern Science and Technology, Vol. 2, No. 4, 2017, Pages 168-178. 

Thermodynamic Sorption Studies of Metal Ions on Polyaniline-Sn(IV)Tungstophosphate: Hybrid Cation Exchanger 

A. Akhtar¹,*, G. Nizami¹, Haroon²
¹Analytical Research Laboratory, Department of Chemistry, ²Physics Laboratory (Electronics), Department of Physics,Sir Syed Faculty of Science, Mohammad Ali Jauhar University Rampur, India-244901.

*Corresponding author’s e-mail:

A novel polymer based organic-inorganic cation exchanger (polyaniline-Sn(IV)tungstophosphate) has been synthesized using a sol−gel method by the incorporation of precipitates of Sn(IV)tungestophosphate into the matrices of polyaniline. It  exhibits good cation exchange capacity as well as thermodynamic properties suitable for ion exchange process and ion exchange equilibria of bivalent [Mg(II), Ba(II)],trivalent [Y(III), Nd(III), Gd(III)] and tetravalent metal ions [Th(IV), Zr(IV)] with the hydrogen form of sorbent have been evaluated at different temperatures 30, 40, 50 and 60oC. Equilibrium constant (K°) and thermodynamic parameters like standard free energy (∆G°), entropy (∆S°) and enthalpy (∆H°) were also determined during the exchange reactions on this ion-exchange material. A correlation has been made for these parameters with the ion exchange characteristics of the exchanger. The variation of selectivity coefficients (log scale) with the equivalent fraction (Xm) of metal ions in the exchanger at constant ionic strength (0.03 M), gives a non-linear function against Xm.

​​Keywords: Exchanger; Ion exchange equilibria; Thermodynamic parameters; Selectivity coefficient.


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ISSN 2456-0235