THE DISSOLUTION BEHAVIOR OF PRESSED DISKS OF COBALT AND ZINC METALS IN SULFURIC-ACID

The dissolution behavior of cobalt, zinc and a mixed cobalt-zinc disc in sulfuric acid solutions have been studied using a rotating disc geometry. The effects of reactant concentrations and disc compositions on the dissolution of the mixed cobalt-zinc disc can be explained in terms of galvanic coupling. It is thought that the dissolution of cobalt from pure cobalt is controlled by the mass transfer of oxygen through the diffusion boundary layer. Zinc from the mixed cobalt-zinc seems to be controlled by both chemical reaction and mass transfer. An empirical model has been developed to predict the dissolution rate of zinc from the mixed cobalt-zinc disc.