Polysulfide immersion gold

The multi-stream chelate ion has a strong complexing ability to gold ions, and the polysulfide compound can effectively dissolve gold under the cooperation of a suitable oxidizing agent or by the deuteration of the polysulfide ion itself. If the leaching process produces elemental sulphur, the sulphide can also be immersed in gold because sulfides and elemental sulphur are easily converted to polysulphide. Polysulfide general how sodium sulfide, calcium polysulfide, ammonium polysulfide and the like, which is suitable for containing arsenic, antimony sulfide concentrates processing of gold. Polysulfides are characterized by strong selectivity, fast leaching, a leaching cycle of several hours, and high leaching rates, as well as low grade gold ore.

The polysulfide immersion gold process (for example, ammonium polysulfide) is a 40% ammonium polysulfide solution leached at room temperature for 1 to 24 hours, and gold is introduced into the solution as NH ₄ AuS, and (NH ₄ ) _{2 is used.} The form of SbS ₃ enters the solution, arsenic is fixed in the slag, and then gold is recovered from the solution with activated carbon. Was thermally decomposed and sulfur Sb ₂ S _3, release ammonia and hydrogen sulfide gas, and a regeneration of sublimed sulfur with ammonium polysulfide. The leaching rate of this method is 80% to 99%, and the obtained arsenic trisulfide contains only 0.07%.

China's Long Bingqing and others have conducted research on the use of polysulfide immersion gold. Zhang, who studied arrows lime sulfur, in essence, a mixture of polysulfide and thiosulfate, they believe that the use lime sulfur, gold and silver leaching rate can reach 96%, 80%, gold leaching cycle 1/8 to 1/2 of the conventional cyanidation method.