MODELS FOR ACTIVATED CARBON - EXTRACTION OF AUROCYANIDE BY POLYXANTHENES, POLYQUINONES AND GRAPHITE

A polyxanthene and a polyquinone have been synthesized and characterized as possible models for activated carbon. These polymers display very high capacities for aurocyanide, which rs possibly adsorbed by an ion-exchange mechanism onto carbonium-ion sites. The quinone functionalities play an important role in the adsorption of phenol onto polyquinone. The polyquinone is slightly selective for Au(CN)(2)(-) over Ag(CN)(2)(-) and base-metal cyanides, whereas the polyxanthene displays no such selectivity. Graphite adsorbs Au(CN)(2)(-) only from acidic solution, which results in the adsorption of gold as insoluble AuCN.