Ion-exchange equilibria of metal ions and hydrogen ions on anilinium tin(IV) phosphate

Summary Ion-exchange equilibria of metal ions (Mn^II, Cu^II, Zn^II, Cd^II and Hg^II)/H⁺ systems have been studied at 30, 40, 50 and 60°C on anilinium tin(IV) phosphate (ATP) as a cation exchanger. The exchange isotherms were measured for both forward and reverse reactions with a solution of ionic strength 0.1 by the batch technique. The isotherms are S-shaped for each ion-exchange system. Selectivity coefficients vary linearly with the equivalent fraction of transition metal ion in the exchanger in the range from 0 to 0.6. The selectivity sequence of zero loading is: Zn^II <Mn^II<Cu^II<Cd^II<Hg^II. Overall and hypothetical (zero loading) thermodynamic data are evaluated.