A sorption study of Pd(II) on aminomethylphosphonic purolite resin S-940

Many methods for the preconcentration-recovery of platinic metals are based on complexing sorbents. As platinic metals have a high tendency to form complexes, the complex-forming sorbents are particularly useful. This study concerns the sorption of Pd(II) on aminomethylphosphonic Purolite S-940 resin. In order to establish the optimum conditions of Pd(II) sorption on S-940 resin, the influence of the following experimental conditions: solution pH, Pd(II) initial concentration and temperature were studied. The yield of Pd(II) recovery was maximum in buffer solutions of pH 3-5 and decreases with increasing initial concentration of the solution. The equilibrium distribution of Pd(II) between the two phases (sorbent and solution) is described by the Langmuir model of monomolecular layer adsorption. The thermodynamic quantities characteristic for the Pd(II) sorption process suggest an affinity of the Purolite resin S-940 for Pd(II).