Platinum Metals Activated Cathodes for the Chloralkali Industry

The chloralkali industry is one of the largest single electricity consumers in the world, and electricity costs can account for about sixty per cent of the running costs of a modern plant. This article, which is based in part upon a paper given at the Third London International Chlorine Symposium, organised by the Society of Chemical Industry, the Chlorine Institute and the Royal Society of Chemistry, which was held in London during June, considers the use in membrane cells of noble metal coated cathodes developed by Johnson Matthey and indicates some of the savings that can result. These coated cathodes, which are being evaluated by a number of chloralkali plant manufacturers, appear to act in a catalytic manner to reduce the cathodic hydrogen overpotential and thus the energy consumption.