Electrogenerative oxidation of ferrous ions with graphite electrodes

Electrogenerative oxidation of ferrous ions in Fe²⁺/O₂ cells to regenerate ferric ions for further use is demonstrated and some results for a hybrid type laboratory-scale reactor are presented. The use of graphite particle, packed-bed anodes for ferrous oxidation with gas diffusion type cathodes for oxygen reduction enables these cells to produce ferric ions at moderate current densities and low cell voltages in sulphuric acid solutions. These cells which utilize the rapid electrochemical, ferrous oxidation rate on graphite catalytic electrodes without any need for an external power source have potential application in hydrometallurgical leaching systems as well as in sulphur dioxide cleanup processes which incorporate the use of ferric ions. Continuous feed stream operation under mild conditions is a special advantage.To whom correspondence should be addressed.