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采用恒界面池法研究了从硫酸介质中萃取In3+和Fe3+的动力学,考察了搅拌速度、界面面积、温度、萃取剂浓度、氢离子活度及硫酸根浓度对In3+,Fe3+萃取速率的影响.结果表明,在温度25℃、搅拌转速70～240 r/min条件下,In3+以三价离子形式被萃取,萃取活化能为17.54 k J/mol,萃取过程为扩散控制;Fe3+以Fe SO4+形式被萃取,萃取活化能为52.87 k J/mol,萃取过程为界面化学反应控制.增加D2EHPA浓度可增大正向反应动力,提高萃取速率.萃取过程为阳离子交换,氢离子活度增加会导致萃取速率降低,硫酸根与金属离子的络合效应会降低萃取速率.通过动力学研究得到In3+萃取的正向速率方程为-d CIn3+/dt=10-0.378[In3+](aq)[H+](aq)-0.376[H2A2](org)0.158,Fe3+萃取的正向速率方程为-d CFe3+/dt=10-2.413[Fe3+](aq)[H+](aq)-1.526[H2A2](org)0.600.
The kinetics of In3 + and Fe3 + extraction from sulfuric acid medium was studied by constant interface cell method. The effects of stirring speed, interface area, temperature, extractant concentration, hydrogen ion activity and sulfate concentration on the extraction rate of In3 + and Fe3 + were investigated. The results show that the extraction activation energy is 17.54 kJ / mol and the extraction process is diffusion controlled. In3 + Fe3 + is Fe3 + in the form of Fe3 +, the temperature is 25 ℃ and stirring speed is 70-240 r / min. The activation energy of extraction and extraction was 52.87 kJ / mol, and the extraction process was controlled by interfacial chemical reaction. Increasing the concentration of D2EHPA increased the positive reaction kinetics and increased the extraction rate. The extraction process was cation exchange and the increase of hydrogen ion activity led to the decrease of extraction rate , The complexing effect between sulfate and metal ions will decrease the extraction rate.The kinetic study shows that the forward velocity equation of In3 + extraction is -d CIn3 + / dt = 10-0.378 [In3 +] (aq) [H +] (aq) - 0.376 [H2A2] (org) 0.158, and the forward rate equation of Fe3 + extraction is -d CFe3 / dt = 10-2.413 [Fe3 +] (aq) [H +] (aq) -1.526 [H2A2] (org) 0.600.