Abstract:
In the electronic and telecommunication industries, gold has been applied for
sinyal strength than other metals such as copper. Gold recovered on electronic
scraps namely computer circuit main board, printed circuit board, handphone
printed circuit board. Based on characterization results, computer circuit board
scraps (CCBs) contains gold and other metals such as copper, lead, alumunium,
ferous, nickel, zinc, and silver. It is essential to separate the precious metal of
CCBs. Generally, gold separation has been done by cyanide and amalgamation
methods. Separation by these methods produce a high gold‘s purity (>80%) and
it can be done in a simple way. Yet, mercury and cyanide are very toxic for
living things, causes death for them. In this research, gold separation of
computer circuit boards (CCBs) has been done by leaching and precipitation
methods. In general, recovery gold of electronic scraps has been done by
pyrometallurgy and hydrometallurgy methods The method was applied in gold
separation processes from modificated methods already existence. This paper
reports a promosing method to separate gold of CCBs. Aqua regia and HNO3
solutions lwere used in the leaching processes, and sodium metabisulphite
(Na2S2O5) was applied in the precipitation process. Silver, Copper, ferous,
alumunium, lead etc. are relatively instable ions and dissolved in HNO3, but gold
is stable as a solid residue in HNO3 solution. Gold separation of solid residue by
leaching with aqua regia. Gold formed a brown solid with the amount precipitated
is 0.089g in the 5g CCBs samples was treated, also gold found high purity
98.9% .
