5709萃取镍(Ⅱ)的宏观动力学研究

Study on the kinetics of nickel (II) extraction with 5709

采用改进的恒界面池进行了异己基磷酸（１－甲基－庚基）酯（国内代号５７０９）－正庚烷体系从硫酸介质中萃取镍（Ⅱ）的动力学研究，以实现钻、镍的萃取分离。研究了水相中镍浓度， ｐＨ值和有机相中 ５７０９的浓度，两相内搅拌器的转速，两相界面积和操作温度对镍（Ⅱ）萃取传质的影响。采用热力学方法处理了实验数据，并建立了相应的数学模型。结果表明，水相中镍离子的扩散和镍的１－２络合物生成的界面化学反应为主要控制步骤。

The kinetics of nickel extraction with 5709 (hexyl- phosphonic acid mono-methylheptyl ester)~heptane was studied in an improved constant interfacial area cell. The effects of the parameters such as rotating rate of stirrers in aqueous phase and organic phase, interfacial area between two phases, operation temperature, and composition of two phases on the extraction rate of nickel were investigated. The experimental data were processed with thermodynamic method, and the process controlling regime was revealed as the mixed controlling reqime, i. e., the diffusion of nickel in aqueous phase and the interfacial chemical reaction of 1-2 complex formation of nickel. The mathematical model for describbing the process was established. The apparent activation energy E was 36.1 kJ/mol.