摘要
利用硫氰酸铵做浸出剂,对除砷、提铜后二次污泥中的银做了浸出试验研究,探讨了浸出剂浓度、反应时间及温度、氧化剂用量及固液比等影因素响,确定了最佳浸银工艺路线及工艺参数.正交试验、单因素优化试验及放大试验表明:硫氰酸铵为95 kg/t、MnO2为6.8 kg/t、浸出温度25℃、液固比为2.5∶1、pH为2时,两次浸银的总浸出率可达95%.对提银反应动力学机理进行了研究,硫氰酸铵浸出反应级数为0.5,活化能为12.574 kJ.mol-1,反应速率常数为:k=1.883 e-12574/RT.
The experiment was carried out for leaching silver by using ammonium thiocyante as leaching agent,and the effect of leaching agent concentration,reaction time,temperature,the dosage of oxidant and liquid-to-solid ratio on leaching efficiency was discussed.The optimal technique route and parameter was proposed.The orthogonal test,single factor optimized test and magnification test showed that when ammonium thiocyante was 95 kg/t,the dosage of manganese dioxide was 6.8 kg/t,leaching temperature was 25 ℃,liquid-to-solid ratio was 2.5∶ 1 and pH was 2,the total rate of silver leaching by twice was up to 95%.The dynamics mechanism of silver leaching was also investigated,and it was found that the leaching reaction order of ammonium thiocyante was 0.5,activation energy was 12.574 kJ·mol-1,the reaction rate constant was k=1.883 e-12574/RT.
出处
《武汉工程大学学报》
CAS
2012年第4期27-31,共5页
Journal of Wuhan Institute of Technology
关键词
冶炼废水
污泥
银
浸出
硫氰酸铵
动力学
smelting waste water
sludge
silver
leaching
ammonium thiocyanate
dynamics
