Activated carbons are attractive as support materials for precious metal catalysts in certain applications. However, the preparation of industrial catalysts can be difficult and unpredictable because of wide batch to batch variations in commercial carbons. This does not mean that carbon manufacturers produce poor quality materials; they are meeting the specifications laid down by those non-catalytic industries which they primarily serve. This paper describes the important features required for chemical process catalysts in terms of active metal location and metal dispersion in relation to activity and selectivity. Redox and acid/base titrations are identified as useful tools for characterising carbons prior to catalyst preparation and can be used as part of the control process to ensure consistent products. The additional properties required for carbon supports for fuel cell applications are corrosion resistance and good electrical conductivity. These are discussed in relation to phosphoric acid fuel cell cathode catalysts and results on platinum/base metal alloy systems on a graphitic support are reported.
