Gold Extraction Method--3.1.1 Ion Exchange Resin

The resin-in-pulp gold extraction process:
(1) Adsorption: there is ion exchange reaction in gold-bearing cyanide solution during resin exchange, and gold is adsorbed on the resin.
(2) Desorption: the gold is adsorb into the solution with the desorption agent. The desorption of weak alkaline gold loaded resin at room temperature and normal pressure can be sodium hydroxide solution with pH=13; for strongly alkaline gold loaded resin the desorption method can be sodium hypochlorite, acidic thiourea, zinc cyanide and sulfur cyanide.
(3) Recovery of gold: zinc replacement, lye precipitation or electrolysis to recove gold from the gold-bearing desorption solution.

The ion exchange resins used for the adsorption of gold from cyanide solution: strong base anion exchange resin AM, AB-17, weak basic ion exchange resin AH-18, 704, mixing basic ion exchange resin AM-2B and A-2. AM-2B was widely used in the production in the former Soviet Union. AM-2B is a difunctional resin of a macroporous structure with better performance than other resins.