In the metal recovery business, activated carbon has been playing a significant responsibility particularly in the extraction of gold. Due to its high porosity characteristic, carbon is used as an adsorbent of gold cyanide complex after leaching the metal by cyanide in aerated alkaline slurries. A method called Carbon in Leach (CIL) used this granulated carbon that is mixed with the pulp that is basically composed of water and ore, subsequently charged by cyanide, and after Silencil overloaded with gold cyanide complex (aurocyanide ion), this loaded carbon is pumped out of the adsorption circuit and sent to elution procedure. The carbon can be recycled following use by putting it back to the adsorption tank or it will be regenerated first to take out the contaminants prior to returning it back to the tank.
With frequent recycling, the carbon turn out to be saturated with contaminants and losses its capability to adsorb. In this event, the carbon has become of no use and ought to be thrown away or else the recovery of gold will suffer. Regeneration of the carbon is a good alternative of this difficulty to eliminate the unwanted contaminants from the shell of the carbon and its pore structure. Regarding to its efficiency, regenerated carbon is proven efficient compared to recycled eluted carbon and in a little difference is efficient than activated fresh carbon. However, small companies don’t use this process due to its expensive maintenance. The kiln that is used in regenerating is a heavy energy consumer and it is more profitable for them to buy fresh carbon than regenerating the eluted one. But in bigger gold companies, they regenerate their carbon for higher recovery and more profit.