废旧电池回收过程中硫酸镍溶液低温除铁试验研究

Removal of Iron From Nickel Sulfate Solution at Low Temperature During Recovery of Spent Batteries

研究了采用铁黄晶种在低温下从硫酸镍溶液中除铁,即在低温常压下,将含铁料液滴加到铁黄晶种溶液中,控制pH,使生成铁黄渣进行除铁。考察了溶液pH、加料速度、反应温度、洗渣液pH、洗渣次数、洗渣液固体积质量比对铁去除率及渣中镍损失的影响。结果表明,在温度50℃、溶液pH为3.5、洗渣液pH=7.0、加料速度13.5 mL/min、搅拌速度300r/min、洗渣2次、水洗液固体积质量比为3∶1条件下,铁去除率达99.90%,除铁后液中铁质量浓度降到10mg/L以下,渣中镍质量分数约0.3%。该法沉淀渣量小,易沉降、过滤和洗涤,可连续除铁。

Removal of iron by dripping the liquid containing iron in crystals solution to form iron yellow slag under the conditions of low temperature,normal pressure and controlled pH was researched.The effects of liquid pH,feed rate,reaction temperature,pH of slag washing liquid,washing slag times and ratio of slag washing liquid-to-solid on removal of iron and nickel content in the slag were examined.The results show that under the optimal conditions that the liquid pH is 3.5,feeding speed is 13.5 mL/min,stirring speed is 300 r/min,reaction temperature is 50 ℃,pH of slag washing liquid is7,washing slag times is 2,and ratio of washing liquid-to-solid is 3∶1,the removal rate of iron reaches 99.90%,and nickel content in the slag is about 0.3%.The precipitated slag is very little,and the slag is easy to settle,filter and wash,and the nickel content in the slag is low.The process can be used for continuous removal of iron in industry.