The Effect of Ag~+ ION Existence in the Cyanidation Process of Tailing of Cijiwa Gold Ore Process on Gold Recovery

摘要

Tailings still contain gold that allows to be extracted again. Some tailings contain silver which can affect the effectiveness of leaching. The purpose of this research is to examine the effect of Ag~+ ion existence on cyanidation process of gold ore processing to Au recovery. The test is done by adding silver nitrate (AgNO_3) to the leaching process. The experiment was conducted five times. The feed capacity was 200 kg with the addition of AgNO_3 of 0 g, 1 g, 2 g, 3 g, and 4 g. The leachate solution was circulated through the activated carbon for 24 hours. Au content in activated carbon was analyzed using atomic absorption spectrophotometry (AAS) method. The results showed that Au recovery in addition of AgNO_3 0 g, 1 g, 2 g, 3 g, and 4 g respectively was 9.62%; 8.99%; 8.91%; 7.30%; and 6.41%. The Ag~+ ion contained in the tailings decreases the Au recovery because the Ag~+ ions can be bound by cyanide ions which interfere with the binding of Au~+ ions by the cyanide ion.