Collect. Czech. Chem. Commun. 2007, 72, 1306-1318

Synthesis, Characterization and Thermodynamics of Exchange Using Zirconium Titanium Phosphate Cation Exchanger

Rakesh P. Thakkar and Uma V. Chudasama*

Applied Chemistry Department, Faculty of Technology and Engineering, The M. S. University of Baroda, Vadodara 390 001, Gujarat, India


A mixed material of the class of tetravalent bimetallic acid (TBMA) salt - zirconium titanium phosphate (ZTP) - has been synthesized by the sol-gel technique. ZTP has been characterized by elemental analysis, thermal analysis (TGA, DTA), FTIR, X-ray diffraction and SEM. Ion exchange capacity (IEC) of the material has been determined and the effect of calcination (373-773 K) on IEC studied and chemical stability of the material in various media (acids, bases and organic solvents) assessed. Further, the equilibrium exchange of H in ZTP for Mg2+, Ca2+, Sr2+ and Ba2+ ions has been studied at 303, 313, 323 and 333 K at constant ionic strength. On the basis of the exchange isotherms, various thermodynamic parameters such as equilibrium constant (K), standard gibbs energy change (∆Go), entropy change (∆So) and enthalpy change (∆Ho) have been calculated. The parameters were correlated with the ion exchange characteristics of the material.

Keywords: Thermodynamics of ion exchange; Ion exchange equilibria; Zirconium titanium phosphate; Cation exchanger; Tetravalent metal acid salt; Tetravalent bimetallic acid salt; Inorganic ion exchanger; Ion exchange isotherm; Thermodynamic parameters.

References: 32 live references.