| The resource of hard-refining gold ores reserves very abundant and distribute widely in China, especially the high-arsenic and high-sulfur gold concentrates. Therefore, the development and utilization of these gold resources has important practical and long-term significance. At the same time, synthesis exploitation of the slag resources can avoid environment pollution, and it's an important way to exploit non-renewable resources, with important environmental and economic benefits.In this experiment, a high-sulfur and high in Xinjiang Gold Concentrate arsenic as the research object, the analysis shows that the grade of gold grade is 50.8-100g/t, the grade of silver is 116-200g/t, contains 32.4% to 46.7% iron and 33.1% sulfur, so such pyrite cinder possesses qualities to leach gold and synthesize polyferric sulphate. The leaching rate of gold is less than 30% only by conventional methods, therefore, a kind of particular aiding agent has been prepared to mask interaction from arsenic, sulfur and copper aiming at such problem, and a qualified PFS was produced, mechanism of the cyanide leaching of gold ore, the leaching of gold associated components influence and the flocculation mechanism of PFS obtained the following conclusions:1.Satisfactory baking sand by roasting pretreatment:The sand contains Arsenic from 0.13% to 0.19%, the grade of sulfur is 0.67%, volatilization rate of arsenic is 94.53%,the removal rate of sulfur is 98.49%. The optimum conditions are:In the arsenic removal stage, the roasting temperature is 450℃,baking time is 90min, the best air flow rate was 4L.min-1;In the desulfurization phase, the calcination temperature was 650℃,baking time is 90min, the best air flow rate was 10～15L.min-12.Gold extraction rate is reached more than 90% by using SxP catalyst. The results show that:After the adsorption with activated carbon, concentration of gold in the lean solution is 0.024mg/L, the silver is 0.058 mg/L. The optimum condition was defined as follows:the amount of sodium cyanide was 3.5kg/t cinder in cyanidation; pH between 10.5 to 11 in cyanidation; solid-liquid ratio is 1:3;cyanide leaching temperature maintained above 20℃;fine grinded granularity is-250 mesh; SxP 8kg/t; cyanide leaching time is 20-24h; final leaching rate reached 92.83 percent. 3.Residue after the leaching of gold is washed with water to remove cyanide, which can be directly extracted acid leaching of iron, and use the sulfuric acid from the process of oxidation roasting pretreatment to the preparation of PFS.Artificial wastewater flocculation test showed that self-PFS has good effect on wastewater treatment. The optimum conditions for artificial wastewater is:dosage of 2mg/L, pH range from 5 to 12, coagulation time was 30min.4. The mechanism of cyanide leaching gold and the influence on leaching process of associated minerals in the baking sand was discussed. Iron has little effect on the process of leaching of gold, arsenic, sulfur and copper on the gold leaching process is extremely hazardous; In addition, the preparation of the PFS and the PFS self-flocculation mechanism are preliminary discussed. |
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