含铜和镍电镀污泥还原氨浸工艺及反应动力学分析

Reductive ammonia leaching of copper and nickel from electroplating sludge and related reaction kinetics

采用还原氨浸工艺实现电镀污泥中铜、镍的浸出。在20%(质量分数)氨水+0.3 mol/L(NH4)2CO3+0.4 mol/L Na2SO3的浸出体系中,当固液比为1∶15,在70℃下浸出3 h,铜、镍的浸出率别为95.84%和90.12%。反应动力学分析表明,氨−碳酸铵−亚硫酸钠体系浸出电镀污泥中铜、镍受界面传质和固体膜层扩散共同控制。

Copper and nickel were leached from electroplating sludge in a reductive ammonia medium.The leaching efficiencies was 95.84%for copper and 90.12%for nickel under the following conditions:ammonia 20wt.%,(NH4)2CO30.3 mol/L,Na2SO30.4 mol/L,solid-to-liquid ratio 1:15,temperature 70℃,and reaction time 3 h.The analysis of reaction kinetics showed that the leaching of copper and nickel from electroplating sludge in the ammonia-ammonium carbonate-sodium sulfite medium is controlled by interfacial mass transfer and solid membrane diffusion.