RECUPERATION OF GOLD AND SILVER IN ARSENI CAL WASTE RESIDUES

This paper reports a technical procedure to extract gold and silver fr om arsenical waste residues. The process goes in three stages. First, An alkaline leaching of the starting material. Second, heating of the solid residues with a sodium chloride. Third, gold and silver extracti on by a cyanuration procedure on a buffered solution. The first leachi ng process separate the 96% of the As and the 64% of the Sb present. H eating of the solid residue with NaCl (13%) eliminates the remaining a ntimonium improving the final extraction of the precious metals.