DIBK-TOPO体系萃取锆和铪的动力学研究  

Extraction Kinetics of Zirconium and Hafnium in DIBK-TOPO System

作　　者：赵骏[1,2] 徐志高[1,2] 张文杰[2] 李攀红[2] 池汝安[2] 徐源来[2] 

机构地区：[1]中南民族大学催化材料科学国家民委-教育部重点实验室,湖北武汉430074 [2]武汉工程大学绿色化工过程教育部重点实验室,武汉430073

出　　处：《稀有金属》2017年第1期108-112,共5页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51174146和51374158);“十二五”国家科技支撑计划项目(2012BAB10B10);教育部新世纪优秀人才支持计划项目(NCET-13-0941);湖北省教育厅优秀中青年科技创新团队项目(T201506);武汉市青年科技晨光计划项目(2014070404010217)资助

摘　　要：采用恒界面池法研究了在NH_4SCN-HCl介质中DIBK-TOPO(二异丁基酮-三辛基氧化膦)体系萃取分离锆和铪的动力学性质,在一定实验条件下分别考察了搅拌速度、温度和界面积对锆铪萃取速率的影响。实验结果表明:当搅拌速度小于135 r·min-1时,锆铪的萃取速率随着搅拌速度的增加而增加,DIBK-TOPO体系对锆铪的萃取类型为扩散反应控制;当搅拌速度在135~155 r·min^(-1)范围内时,锆铪的萃取速率分别出现一段与搅拌速度无关的坪区,但锆的萃取速率常数与比界面积无关,对锆的萃取类型为相内化学反应控制类型,其表观活化能为-11.963 k J·mol^(-1),铪的萃取速率常数随着比界面积的增加而线性增加,且直线不通过坐标原点,因而对铪的萃取类型则为混合控制类型,其表观活化能为-22.406 k J·mol^(-1);当搅拌速度超过155 r·min^(-1)时,因搅拌速度过快,造成两相界面出现混乱而不稳定。升高温度不利于DIBK-TOPO体系对锆和铪的萃取。The extraction kinetics of zirconium and hafnium from NH4SCN-HC1 medium by the mixture of DIBK （diisobutyl ketone） and TOPO （tri-n-octyl phosphine oxide） was studied using a Lewis Cell. Under the given conditions, the effects of interfacial area, temperature and stirring speed on the extraction rate were separately investigated. The experiment results showed that when the stirring speed was less than 135 r·min^-1, the extraction rates of zirconium and hafnium in the DIBK-TOPO system increased with the increase of stirring speed. When the stirring speed was in the range of 135 - 155 r·min^-1 , the extraction rates of zirconium and hafnium had a plateau region which did not vary with the stirring speed. But the extraction rate constant of zirconium was not related with the specific interfacial area, the type of extraction of zirconium was controlled by chemical reactions at bulk phase with the activation energy of - 11. 963 kJ·mol^-1. While the extraction rate constant of hafnium increased linearly with the increase of the specific interfacial area and the line passed through the origin of coordinates, the type of extraction of hafnium was controlled by mixed-control with the activation energy of -22. 406 kJ·mol^-1. When the stirring speed was more than 155 r·min^-1, the phase interface was chaotic and unstable because the mixing speed was too fast, and it was not conducive to extraction operation. Elevated temperature was not conducive to the extraction of zirconium and hafnium in DIBK-TOPO system.

关 键 词：恒界面池法 萃取动力学 DIBK TOPO 锆 铪 

分 类 号：TF841.4[冶金工程—有色金属冶金]