Johnson Matthey & Co., Limited

Christopher William Bradford

Harry Middleton

Stephen George Baldwin

In order to recover platinum, rhodium and other precious metals from catalysts employed in internal combustion engine exhaust systems, the used or unused catalysts, preferably in crushed, powdered or broken form, are reacted with an acidic medium having oxidizing properties to leach out the precious metals. The acidic medium may be an acid containing or oxidizing agent or an oxidizing acid and when a used catalyst is treated the leaching step is preferably preceded by a reduction step in order to convert to the metal any precious metal oxides present in the catalyst.

Recovery of PT/RH from car exhaust catalysts

This invention relates to gold compounds useful in electroplatings and which are obtained by reacting an alkali metal gold sulphite with an alkali metal nitrite.

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London, United Kingdom

Christopher William Bradford