Ligand adsorption of adenine and adenosine on poly(vinyl chloride) bound cobalt(II)–carboxylated diaminoethyl complex

Ligand adsorption of adenine and adenosine has been studied by using cobalt(II)–poly(vinyl chloride) carboxylated diaminoethyl (PVC–CDAE) resin. Column runs were conducted to study the performance of the ligand exchanger. The adsorption of adenine and adenosine from solutions of different initial concentrations onto resin was measured using by breakthrough technique at 25 °C. The ligand concentration was chosen to be 0.0125–0.2 mmol l−1. The characteristics of the adsorption process were investigated by using Scatchard plot analysis (q/C versus q). And the adsorption behaviour of these ligands on cobalt(II)–PVC–CDAE is expressed by the Langmuir and Freundlich isotherms. The adsorption data with respect to all ligands provide an excellent fit to the Freundlich isotherm, giving correlation coefficients in the range of 0.95–0.99 for the Freundlich isotherm. On the contrary, when the Langmuir isotherm model was applied to these data, a good fit was not obtained for the high ligand concentrations.