摘要 |
<p>For recovering metals adsorbed as ionic alkaline earth metal complexes on a carrier, in particular gold, silver, nickel or copper, an alkali metal cyanide solution, an alkali metal hydroxide solution or a mixture thereof is used for pretreating the carrier. The said solution preferably contains alkali metal cyanide in a concentration of 1 to 10% by weight and alkali metal hydroxide in a concentration of 1 to 20% by weight, the concentration of cyanide ions in general exceeding the concentration of hydroxyl ions. The process leads to high yields with respect to the recovery of especially rare metals.</p> |