摘要
The separation and recovery of Ni from the copper electrolyte by crystallization of nickel ammonium sulfate double salt were studied.It is found that the solubility of copper sulfate at the same temperature is less than that of nickel sulfate,while the solubility of copper ammonium sulfate is greater than that of nickel ammonium sulfate.So,by adding(NH_(4))_(2)SO_(4),the Ni can be selectively crystallized from the copper electrolyte.By adding(NH_(4))_(2)SO_(4)at the molar ratio of(NH_(4))_(2)SO_(4)/NiSO_(4)≤0.8,and crystallizing at−15℃for 10 h,the Ni in the copper electrolyte can be crystallized in the form of Ni(NH_(4))_(2)(SO_(4))_(2)×6H_(2)O.The qualified product of NiSO_(4)×6H_(2)O can be obtained by pyrolyzing the crystals,dissolving the pyrolysis product in water,and then concentrating the dissolved solution for crystallization.The method of double salt crystallization is a clean,environmentally-friendly,cost-effective and efficient method for separating and recovering nickel from copper electrolyte.
研究采用硫酸镍铵复盐结晶从铜电解液中分离回收镍的方法。研究发现,在相同温度的溶液中,硫酸铜的溶解度小于硫酸镍的溶解度,而硫酸铜铵的溶解度大于硫酸镍铵的溶解度。因此,加入(NH_(4))_(2)SO_(4)可使铜电解液中的镍选择性结晶析出。按(NH_(4))_(2)SO_(4)/NiSO_(4)摩尔比≤0.8加入(NH_(4))_(2)SO_(4),在−15℃冷冻结晶10 h,可使其中的镍以Ni(NH_(4))_(2)(SO_(4))_(2)×6H_(2)O的形式结晶析出。将所得结晶物热解,再将热解产物加水溶解,最后将溶解液浓缩结晶得到合格的NiSO_(4)×6H_(2)O产品。复盐结晶法是一种清洁环保、经济高效的从铜电解液中分离回收镍的方法。
基金
the National Natural Science Foundation of China(No.50274075).
