Abstract The experiment on recovery of gold and iron by one-step chlorination-reduction roasting in the muffle furnace was conducted using cyanide tailings from a gold smelting enterprises (Henan Province, China) as research object. The effects of the dosage of calcium chloride, dosage of bituminous coal, roasting temperature, roasting time, and other factors on the high-temperature chlorination efficiency of gold were studied. The effects of iron reduction were also investigated. X-ray diffraction analysis on the roasting products was carried out. Results showed that the high-temperature chlorination efficiency of gold increased with the rising of calcium chloride dosage. The high-temperature chlorination efficiency of iron also increased, leading to iron loss. The concentration of CO and CO2 produced by bituminous coal increased in roasting atmosphere, leading to the decrease of chlorine gas concentration. Thus, the high-temperature chlorination efficiency of gold decreased. During the roasting process, the reduction process of iron oxide is Fe2O3 → Fe3O4 → FexO → Fe, and the wustite can easily react with the silicon dioxide to form iron silicate in the weak reduction atmosphere. Under the condition of calcium chloride dosage of 6%, bituminous coal dosage of 22%, roasting temperature of 1200 °C, and roasting time of 1.5 h, the technical indices of gold high-temperature chlorination efficiency of 83.1%, iron grade of 92.0%, and iron recovery of 84.9% were obtained. The relationship between the high-temperature chlorination efficiency of gold and roasting temperature was established. The high-temperature chlorination reaction of gold was controlled by the interfacial chemical reaction. The apparent activation energy of the high-temperature chlorination of gold is calculated to be E = 20.3 kJ/mol.

中文翻译：

---

一步氯化-还原焙烧从氰化物尾矿中回收金和铁的动力学

摘要 以河南省某黄金冶炼企业氰化尾矿为研究对象，进行了马弗炉一步氯化还原焙烧回收金和铁的实验。研究了氯化钙用量、烟煤用量、焙烧温度、焙烧时间等因素对金高温氯化效率的影响。还研究了铁还原的影响。对焙烧产品进行 X 射线衍射分析。结果表明，金的高温氯化效率随着氯化钙用量的增加而增加。铁的高温氯化效率也增加，导致铁损。烟煤在焙烧气氛中产生的CO和CO2浓度升高，导致氯气浓度降低。因此，金的高温氯化效率降低。在焙烧过程中，氧化铁的还原过程为Fe2O3→Fe3O4→FexO→Fe，方铁矿在弱还原气氛中很容易与二氧化硅反应生成硅酸铁。在氯化钙用量6%、烟煤用量22%、焙烧温度1200℃、焙烧时间1.5h条件下，金高温氯化效率技术指标为83.1%，铁品位92.0 %，铁回收率为 84.9%。建立了金的高温氯化效率与焙烧温度之间的关系。金的高温氯化反应受界面化学反应控制。金的高温氯化的表观活化能计算为 E = 20.3 kJ/mol。