湿法冶金

研究了用二甲苯浸出—焙烧—硫酸浸出杂质—氰化浸出银工艺从湿法炼锌渣中回收硫和银。试验结果表明:在反应温度95℃、反应时间15min、液固体积质量比5∶1条件下用二甲苯浸出,硫浸出率为96.40%;分硫渣中加入1%氢氧化钠,在630℃下焙烧2h,然后用硫酸浸出锌、铁等杂质,控制液固体积质量比为4∶1,pH为1.0,反应温度为95℃,反应时间为3h;之后对硫酸浸出渣氰化浸出银,体系pH控制在9.5~11.5之间,液固体积质量比为3∶1,氰化钠质量浓度2.0g/L,浸出时间24h,银回收率为78.5%。

Recovery of silver and sulfur from zinc smelting residue by dimethylbenzene leaching sulfurroasting-sulfuric acid leaching impurities-cyanide leaching silver process is investigated.The result show that the leaching rate of sulfur is 96.40%under the conditions of reaction temperature of 95℃, reaction time of 15 min and the ratio between liquid volume and solid mass of 5∶1.The roasting conditions of sulfur leaching residue are adding sodium hydroxide of 1% into the residue,roasting temperature of 630℃,roasting time of 2h.The conditions of leaching impurities using sulfuric acid are the ratio between of liquid volume and solid mass,system pH of 1.0,reaction temperature of 95 ℃,reaction time of 3h.The cyanide leaching silver under the conditions of system pH of 9.5-11.5, the ratio between liquid volume-solid mass of 3∶1,sodium cyanide concentration of 2g/L,reaction time of 24h,the leaching rate of silver is 78.50%.