Possibility of using strongly basic anion exchange resin of MINIX brand and weakly basic anion exchange resin Purogold S992 brand in the high-temperature-caustic conditioning (HiTeCC) technological process for diminishing the loss of gold via adsorption on natural organic carbon-containing substances (pregrobbing phenomenon) in the course of cyanide leaching was studied. It was shown that the strongly basic anion exchanger MINIX has a higher affi nity for the anion [Au(CN) 2 ] -, compared with the microporous activated carbon WSC-207C-GR. As a result, the adsorbed dicyanoaurate(I) anion is transferred from the activated carbon to the ion-exchange resin. Reasons for binding of the dicyanoaurate(I) anion with active centers of activated carbons are considered, based on the fact that the adsorbent contains carbene-like carbon atoms. The existence of paramagnetic centers belonging to carbon atoms in the activated carbon was demonstrated by the EPR method. The suggested concept was used to diminish the loss of gold via partial oxidation of metallic gold in autoclave processing of pyrite-and arsenopyrite-containing concentrates.

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