| 摘要 |
<p>PURPOSE:To provide the distribution phase convenient for recovery of gold by blowing gaseous Cl2 to the precipitate of copper electrolysis or decopperization which is made into a slurry by using an aq. NH4Cl soln. thereby performing chlorine leaching. CONSTITUTION:The precipitate of copper electrolysis byproduced in an electrolytic refining stage of copper, more preferably the so-called precipitate of decopperization subjected to decopperization and dearsenization is made into a slurry by using an aq. 1-5N, more particularly 2.5-3.5N NH4Cl soln. Gaseous Cl2 is blown to the slurry at 60-80 deg.C under stirring. The precipitate blown with the gaseous Cl2 for the prescribed period is converted to the decoction in which gold is eluted at <=99% and the residue in which silver is held in the form of AgCl. Said decoction and residue are subjected to a post treatment for the purpose of recovering the valuable elements contg. respectively therein after the solid-liquid sepn. Pt and Pd are migrated into the AgCl residue in the form of insoluble compd. respectively at >=85% and >=98% yields by the above-mentioned method. The rate of migration of Pb and Te to the liquid after leaching is considerably decreased and the rate of migration of Sb to the liquid after leaching is decreased as well as compared to an NaCl method.</p> |
