Removal of mercury from leach solutions with surface-active reagents

In the world , cyanidation is the most common method for gold production which has increased rapidly in recent years. In addition, a remarkable method of amalgamation is still used. Mercury (Hg) dissolves in the cyanidation process and causes many environmental and economic problems. Therefore; searching that selective and low cost separation methods of Hg from cyanide solutions and stabilization of Hg have become important. In this study, firstly, the type of reagent to be used in precipitation was determined and the effect of parameters such as reagent concentration, duration, pH, temperature on Hg removal was investigated. The products obtained as a result of the process are characterized. Also, the applicability of the process to the cyanidation solution of amalgaming waste has been tested. In the results of working; precipitator dosage, pH and temperature were determined to be highly effective in Hg removal efficiency depending on the precipitator type. It has been determined that Au, silver (Ag) and copper (Cu) do not affect Hg removal efficiency and do not form any precipitate with xanthate. The best result was obtained with potassium ethyl xanthate (KEX) and the Hg concentration was reduced from 10000 ppb to 5 ppb in 99.9% yield. It has been determined that highly stable metazinober (H-HgS) is formed as precipitate. The concentration of Hg in cyanidation solution of amalgaming waste was reduced from 9539 ppb to 101 ppb in 99% yield by using 8.1x10-5 mol KEX. As a result, it has been determined that it is possible to remove Hg from cyanide solutions with xantates selectively with high efficiency.