Thermodynamics and kinetics of adsorption of cyanide ions on silver .1.

The adsorption of cyanide ions on silver has been studied by measuring the electrode impedance. It has been found that in the region of potentials E < -0.5 V (SHE), the process under study involves the stage at which the substance is supplied to the electrode and the adsorption-desorption stage itself. At more positive potentials, the process becomes more complicated. The capacity of the electric double layer and the potential of zero charge have been determined. It has been established that in the description of the adsorption of cyanide ions on silver, the potential of the electrode E rather than its charge should be used. At E < -0.5 V (SHE), the adsorption is represented by the Parsons isotherm, and at E > -0.5 V (SHE) by the virial isotherm. The structure of the electric double layer is considered. The components of the integral capacity of the compact layer are calculated as single-valued functions of the electrode potential. The standard Gibbs adsorption energy and its electrostatic and non-coulomb components are calculated. (C) 1997 Elsevier Science S.A.