Supercritical carbon dioxide elution of gold - Cyanide complex from activated carbon

The elution of gold from activated carbon using supercritical carbon dioxid e is reported. Results of the conditions that maximize recovery of gold are presented. The parameters that were investigated include pressure, solvati ng agent, ionic strength, and static mode time. Repeating short static time periods followed by dynamic periods (on the same gold-loaded carbon sample ) yielded higher recoveries compared to longer static time periods. It is p roposed that the desorption process is kinetically controlled. The standard deviation for the recovery process was 7.6% or better.