The thiocyanate leaching gold may be NH 4 SCN or NaSCN. The latter is a by-product of the coking plant, which is inexpensive and readily available, and does not release ammonia during the process. Use thiocyanate method, dissociation can be at room temperature SCN - with the Au +, Ag + to generate more stable complex. The oxidizing agent (MnO 2 or the like) added to the acidic (pH 1 to 2) solution can decompose the gold-bearing mineral (FeS 2 or the like) to release the monomer gold, thereby accelerating the leaching speed of gold and silver and increasing the leaching rate. However, as the pH of the solution increases, the gold in the carrier mineral is not easily dissociated, and the leaching rate of gold is continuously decreased. During the leaching process, the thiocyanate has stable performance and does not substantially pollute the environment. Literature, light, pH, CuS, PbS, Fe 3 +, Fe 2 + Effect of ammonium thiocyanate and the like is not large, and the soluble copper salt (such as CuSO 4) is influenced, and with the amount of addition Increased consumption is increasing rapidly. When 100 mL of 2.5% NH 4 SCN solution of pH 1 was added, 0.1 to 1.0 g of CuSO 4 ·5H 2 O was added, and after 1 h, the consumption of NH 4 SCN was 0.1 g of 1 g, 0.4 g was 5.5%, 0.6g is 8%, and 1.0g is 25.5%. MnO 2 also has a large effect on thiocyanate, especially in strongly acidic solutions, its consumption increases with the increase of MnO 2 addition and time. When added to 100ml 2.5% NH 4 SCN solution pHl in 0.5gMnO 2, 5hNH 4 SCN consumption by about 3%; when MnO 2 was increased to 2.0g 5h, consumption increases to about 8%. However, the addition of MnO 2 to the acidic solution can oxidize the FeS 2 in the ore or concentrate to dissociate the encapsulated gold into monomers, which is beneficial to increase the leaching rate of gold. Sino Howo Truck Co Ltd. , https://www.sinotruk-howo.com