The pickling rate with Acidon 4201 depends only on the Acidon 4201 concentration and pickling solution temperature. The build-up of copper does not effect pickling rates in any way until the bath is saturated with cupric ions. The method is adaptable to continuous operation and can be concentrated. This recovery method takes advantage of the decrease in copper nitrate solubility with decreasing temperatures. The use of centrifugal filter on a continuing basis is suggested for large scale installations.
Centrifugal filters can produce a relatively dry salt.
Electrolysis - this method of copper recovery has the advantage of recovering copper as metal and regenerating the acid in the process. Electrolytic recovery of copper from Acidon 4201 solution is quite simple. Contact General Chemical for suggestions on electrolytic recovery relative to your specific plant application. In solution, various compositions are possible, depending upon the particular requirement and the alloy to be picked. The higher temperatures give higher pickling rates.