Cyanide Process. Cyanide process is also called as Macarthur forest Process. It is the process of extracting gold or silver from the ores by dissolving in a dilute solution of potassium cyanide or sodium cyanide. This process was introduced in the year 1887 by the Scottish chemists naming Robert W. Forrest, John S. MacArthur, and William Forrest.
If the solution is rich enough can be treated by zinc powder and the precipitated obtained obtained will be sent to retorting and smelting. For gold extraction the strength of cyanide solution ranges from 0.01 to 0.05%. Lime is added to the process in order to have a pH near to 10 11.
Removing the gold bearing rock from the ground is just the first step. To isolate pure gold, mining companies use a complex extraction process. The first step in this process is breaking down large chunks of rock into smaller pieces. At a mill, large machines known as crushers reduce the ore to pieces no larger than road gravel.
6 M3TC Report GOLD EXTRACTION AND RECOVERY PROCESSES Cyanide Process It is the most common used process for gold extraction. This process involves the dissolution of gold from the ground ore in a dilute cyanide solution in the presence of lime and oxygen according to the ...