锌丝置换氰化镀银废水中低浓度银的研究及应用  

Recovery of silver in wastewater from cyanide silver plating by replacement with zinc wire

作　　者：李春艳 李瑞 张俊 姚女 焦少俊 LI Chunyan;LI Rui;ZHANG Jun;YAO Nü;JIAO Shaojun(Nanjing Institute of Environmental Science,Ministry of Ecology and Environment,Nanjing 210000,Jiangsu,China;Zhoushan Solid Waste Pollution Control Center,Zhoushan 316000,Zhejiang,China)

机构地区：[1]生态环境部南京环境科学研究所,南京210000 [2]舟山市固体废物污染防治中心,浙江舟山316000

出　　处：《贵金属》2023年第3期51-56,共6页Precious Metals

基　　金：国家重点研发专项(2018YFC1902802:复杂来源典型危险废物分级分类管理技术研究项目)。

摘　　要：氰化镀银工艺产生了大量的含银清洗废水,采用锌丝置换氰化镀银漂洗废水中的低浓度银有助于节约资源、保护环境。考察了锌丝用量、反应时间、温度、p H值、搅拌速度对银回收率的影响。最佳置换条件为,锌丝用量1 g/200 mL,pH值8~9,温度30℃,搅拌速度400 r/min,反应时间30 min,银置换率99.44%。动力学分析表明,氰化镀银漂洗废水中银的置换反应符合一级动力学,扩散为控制步骤,以反应Arrhenius方程计算出反应活化能为19.95 kJ/mol。参考研究结果,设计了回收装置,银回收率99%,回收成本比树脂法低。A large amount of silver-containing wastewater is produced from the silver cyanide plating process.Recovery of silver and purification of the discharge are very important in saving resources and protecting the environment.In this study,zinc wire was used to recover silver from such silver-containing wastewater via the replacement reaction.The effects of zinc wire dosage,reaction time,temperature,pH and stirring speed on silver recovery were investigated and evaluated.Optimal replacement conditions are as follows:the dosage of zinc wire is 1 g/200 mL,pH 8~9,30℃,stirring speed 400 r/min and reaction time 30 min.The replacement rate of silver was 99.44%.The kinetic analysis shows that the reaction conforms to first-order kinetics and the diffusion is the rate determing step.The Arrhenius activation energy is 19.95 kJ/mol.Based on these results,a recovery device was set up and the overall recovery cost was lower than that of the resin method.

关 键 词：氰化镀银 漂洗废水 锌丝 置换 回收装置 

分 类 号：X703[环境科学与工程—环境工程] TF832[冶金工程—有色金属冶金]