响应曲面法优化含银浸出渣浸银工艺研究

The Process Optimization Study on Immersion Silver from Silver-bearing Leach Residue by Response Surface Methodology

以云南某有色冶炼厂湿法含银浸出渣为考察对象,采用硫脲法回收其中的银。实验结果为反应时间5 h、硫脲用量为40 g/L、反应液固比8 mL/g、Fe_2(SO_4)_3用量为0 g/L、浸出温度60℃。在此条件下,所得银浸出率大于88%。以反应时间、硫脲用量、反应液固比为考察因素,通过响应曲面法对该浸银工艺进行优化,得到银浸出率的预测回归方程,其优化得到的工艺条件为反应时间6 h、硫脲用量为50 g/L、反应液固比10 mL/g,在此条件下所得银浸出率91.40%,与理论银浸出率92.15%的结果相差较小,说明预测回归方程和优化的工艺条件可以实际应用。

The thiourea process is adopted to recover silver in the investigation object that the silver-bearing leach residue of one Yunnan nonferrous smelting plant. The test conditions are the reaction time is 5h, the thiourea dosage is 40g/L, the reaction liquid-soild ra- tio is 8mL/g, Fe2 （SO4）3 dosage is 0g/L, the leaching temperature is 60℃. Under the above mentioned conditions, the silver leaching rate is more than 88%. The study factors are reaction time, thiourea dosage, reaction liquid-solid ratio, the immersion silver process is opti- mized by response surface methodology, so the predicted regression model of silver leaching rate is obtained, the optimal process conditions are： the reaction time is 6h, the thiourea dosage is 50g/L, the reaction liquid-solid ratio is lOmL/g, under these conditions, the leaching rate of silver is 91.40%, which has little difference to the theoretical silver leaching rate 92.15%, which means the predicted regression model and the optimal process conditions can be applied in practical application.