Operation of the ferrous chloride electroforming solution

Summary

Electrochemical studies of cathodic electrodeposition of iron from hot concentrated ferrous chloride solution show that the gradual build-up of ferric ions by oxidation causes various deleterious effects which maybe recognised in terms of changes in polarisation, lowering of current efficiency and precipitation of basic salts in solution. Oxidation occurs by anodic reaction as well as atmospheric and anodic oxygen and means of controlling or eliminating it have been investigated. These include electrochemical reduction, introduction of a membrane by design of a divided cell and use of powerful chemical reducing agents. A range of possible insoluble anode materials have been investigated and it is concluded that graphite is the most acceptable.