THE CEMENTATION OF AG(I) IONS FROM SODIUM-CHLORIDE SOLUTIONS ONTO A ROTATING COPPER DISC

The kinetics of cementation of silver chloro-complexes from sodium chloride solutions onto copper was studied using rotating disc electrode systems. Activation energies were found to be 10.8 and 8.0 kJ/mol for 3 M and 4 M NaCl solutions, respectively, confirming that the rate of reaction is controlled by the mass transfer of the precipitating ions onto the precipitant surface, The effect of temperature, concentration of NaCl, Ag(I), and Cu(I) were studied. Scanning electron microscope studies were conducted to evaluate the deposit morphology and its effect on reaction kinetics. Evans diagrams were constructed from current potential data for the dissolution of copper from a copper disc and for the deposition of silver onto a glassy carbon electrode to show the effect of NaCl and dissolved copper concentrations.