硫酸介质中D2EHPA萃取In^(3+)与Fe^(3+)的动力学  

Extraction Kinetics of Fe^(3+) and In^(3+) from Sulfuric Acid Medium with D2EHPA

作　　者：荣浩[1] 李兴彬[1] 魏昶[1] 朱如龙[1] 李旻廷[1] 邓志敢[1] 

机构地区：[1]昆明理工大学冶金与能源工程学院,云南昆明650093

出　　处：《过程工程学报》2015年第2期224-229,共6页The Chinese Journal of Process Engineering

基　　金：国家重点基础研究发展规划(973)基金资助项目(编号:2014CB643404);国家自然科学基金资助项目(编号:51304093;51174104;51304093)

摘　　要：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.Extraction kinetics of trivalent In3＋ and Fe3＋ with di（2-ethylhexyl） phosphoric acid （D2EHPA, H2A2） in kerosene from sulfuric acid medium was studied using constant interracial area method. The effects of temperature, interracial area, stirring speed, hydrogen ion, D2EHPA and sulfate concentration on their extraction rate were examined. The results indicated that at 25℃ and stirring speed of 70-240 r/min, the apparent activation energy of In3＋ extraction was 17.54 kJ/mol and the extraction process of In3＋ was controlled by diffusion, while the apparent activation energy of Fe3＋ extraction was 52.87 kJ/mol, Fe3＋ was extracted in FeSO4＋, and the extraction process was controlled by chemical reaction at the interface. As D2EHPA concentration increased, the forward reaction force could be increased to improve the extraction rate. Because the extraction process was the cation exchange, increasing the concentration of hydrogen ion would reduce the extraction rate. Complexation of metal ion with sulfate radical would reduce the extraction rate. Under those conditions, the rate of forward In3＋ extraction reaction was expressed as -dCIn3＋/dt=1 0.378 3＋]（aq）H＋（aq）-0.376[H2/A2]（org）0.158, and that of Fe3＋ as -dCFe3ddt=1 0-2.431 [FeS＋]（aq）[H＋]（-l.526[H2A2]（ors）0.600.

关 键 词：D2EHPA In3+ FE3+ 萃取 动力学 恒界面池法 

分 类 号：O643.12[理学—物理化学]