MRT Africa, a BATEMAN subsidiary, is to supply a micro PGM (platinum-group metal) refinery to Harmony Gold Mines Limited. The plant will recover saleable-grade palladium, platinum, iridium, rhodium and ruthenium from gravity-concentrated feedstock recovered from new mining feed to a gold plant in the Evander area, RSA.

According to Petrus Cilliers, General Manager, MRT Africa, the refinery embodies proprietary SuperLig MRT (molecular-recognition technology) resins supplied by IBC Advanced Technologies, Inc. (IBC), USA. "The micro refinery was selected by Harmony, to replace an existing large bench-scale plant, because of its operability and the high recovery rates of the PGMs," says Cilliers.

The metals will be dissolved out of the gravity-concentrated feed using hydrochloric acid and selectively stripped out of the solution in columns loaded with SuperLig resins. Gold dissolved in the dissolution step will also be recovered.

The MRT resins are highly specific and will selectively target specific metals, provided the appropriate conditions of pH, oxidation state and ligand content are established in the solutions. Similarly, the elution of the loaded metals occurs only under specific conditions. The eluted metals will usually be recovered from solution by the addition of sodium hydroxide to precipitate the metals.

The refinery will be fully instrumented, providing all the controls necessary to ensure the required conditions for loading, elution and precipitation.

"The processing technology to be incorporated into the refinery is well proven," claims Cilliers. "MRT resins are
used routinely in the palladium circuit at the Impala EPMR facility in Springs, RSA. Rhodium and ruthenium circuits have been used successfully in pilot plants in Japan and platinum has been processed in an MRT circuit there."

"This contract to supply a plant to Harmony is the breakthrough we have been working towards," says Cilliers."The possibilities of this type of technology will soon be appreciated by other small-scale refiners of PGMs and producers of autocatalysts and jewellery. It would also be easy to scale up the plant to handle the needs of primary producers of PGMs."

For more information, please contact Neill Birdsey,
General Manager, Small Projects, on +27-11-899-3191 or
email tawana@batemanengineering.com.

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