METHOD FOR RECOVERING GOLD OF SILVER FROM AQUEOUS SOLUTION CONTAINING FREE CYANOGEN AND GOLD OR SILVER CYANIDE

摘要

PURPOSE:To separate and recover efficiently Au, Ag or the like from an aqueous soln. contg. the cyanide of Au, Ag or the like by adjusting the pH of the soln. and passing the soln. through a layer of activated carbon at a specified velocity. CONSTITUTION:The pH of a waste plating soln. contg. free cyanogen and the cyanide of a valuable metal such as Au or Ag is adjusted to <=6.0 by adding a mineral acid such as sulfuric acid. A layer of activated carbon of 0.3-3mm. grain size is treated with dil. sulfuric acid and washed, and said aqueous soln. contg. Au, Ag or the like is passed through the layer at 5-20 velocity SV. The valuable metal such as Au or Ag in the aqueous soln. is adsorbed on the activated carbon. The carbon is roasted and treated in a silver parting furnace to recover Au or Ag in a high yield.