(北京工业大学 材料科学与工程学院，北京 100124)
摘 要: 根据质量守恒和同时平衡原理，以Me(Co、Ni、Fe、Mn)为金属元素，建立Me-OH-、Me-OH--CO32-、Me-OH--S2-、Me-OH--NH3和Me-OH--NH3-CO32-等多个配合-沉淀体系的热力学平衡模型。结果表明：Fe3+可以在Me-OH-、Me-OH--NH3体系中通过调节pH=3预先沉淀分离，而Co、Ni、Mn仅在Me-OH--NH3-CO32-体系中有分离效果。Me-OH--NH3-CO32-体系热力学计算表明：Co、Ni、Mn在溶液中的行为受pH值、配合剂、沉淀剂浓度共同影响，碳酸根初始总浓度[C]增大和氨初始总浓度[N]减小有利于Co、Ni、Mn形成沉淀。当[C]=1 mol/L、 [N]=2 mol/L、pH值为9~10时，大部分Ni以高级氨配离子[Ni(NH3)42+]、[Ni(NH3)52+]、[Ni(NH3)62+]的形式保留在溶液中，而Co、Mn以MnCO3、CoCO3的形式沉淀出来。Co可在Me-OH--S2-体系中通过调节pH<6从溶液中与Mn分离。研究结果可为钴镍二次资源综合回收钴镍、制备钴镍产品提供理论指导。
关键字: 配合-沉淀体系；热力学；钴镍二次资源
（College of Material Science and Engineering, Beijing University of Technology, Beijing 100124, China）
Abstract:Based on mass balance principle and simultaneous equilibrium principle, the metal element Me (Co, Ni, Fe, Mn), complexing agent of OH- and NH3, and precipitant of OH-, S2- and CO32- were chosen to form the complexation–precipitation systems of Me-OH-, Me-OH--CO32-, Me-OH--S2-, Me-OH--NH3 and Me-OH--NH3-CO32-. The thermodynamic equilibriums of these systems were studied. The results show that Fe3+ in systems of Me-OH- and Me-OH--NH3 can be separated by precipitation through adjusting the pH value to 3. However, Co, Ni and Mn can be separated only in Me-OH--NH3-CO32- system. The theoretical calculations show that the behavior of Co, Ni and Mn in Me-OH--NH3-CO32- system is affected by pH value, complexing agent concentration and precipitant concentration. The increase of the total concentration of carbonate [C] is in favor of the precipitation of Ni, Co and Mn, but the increase of the total ammonia concentration [N] has the opposite effect. When [C]=1 mol/L, [N]=2 mol/L and pH value of 9-10, most Ni is complexed in the solution in the form of senior ammonia complexes [Ni(NH3)42+] and [Ni(NH3)52+], [Ni(NH3)62+], while Co and Mn precipitate in MnCO3 and CoCO3. Finally, Co can be separated with Mn from the solution in Me-OH--S2- system when pH<6. The results provide a theoretical guidance for cobalt and nickel recovery from secondary resources and the preparation of cobalt and nickel products.
Key words: complexation-precipitation system; thermodynamics; secondary resources of cobalt and nickel
