P204-[P4446][NTf_(2)]离子液体体系非皂化萃取Nd的研究  

Non-Saponifiable Extraction of Nd with P204-[P4446][NTf_(2)]Ionic Liquid System

作　　者：帅国胜 赵永志[1] 马莹[1] Shuai Guosheng;Zhao Yongzhi;MaYing(State Key Laboratory of Baiyunobo Rare Earth Resource and Comprehensive Utilization,Baotou Research Institute of Rare Earths,Baotou 014030,China;College of Chemistry and Chemical Engineering,Inner Mongolia University,Hohhot 010020,China)

机构地区：[1]包头稀土研究院,白云鄂博稀土资源研究与综合利用国家重点实验室,内蒙古包头014030 [2]内蒙古大学化学化工学院,内蒙古呼和浩特010020

出　　处：《稀有金属》2023年第3期390-398,共9页Chinese Journal of Rare Metals

基　　金：科技部国际合作交流项目(白云鄂博稀土资源研究与综合利用国家重点实验室项目)(2020Z2137,2020Z2208)资助。

摘　　要：在资源综合利用方面,低浓度废水中有价金属的回收具有很大研究空间,而探索一种将不易挥发的稀释剂与非皂化萃取过程相结合的方法解决相应问题,有利于实现环境友好的目的。采用P204-[P4446][NTf_(2)]离子液体体系进行稀土金属Nd3+的非皂化萃取实验。比较了不同介质中萃取率及萃取现象上的差异,探究其萃取机制;从萃取平衡时间、温度等方面,确定了最佳萃取条件,分析了热力学过程;在相同浓度条件下,从相比及传质扩散理论两方面探究了不同介质中不同浓度水相的萃取规律及产生原因。在pH 4.0,摩尔比(n(P204)∶n(Nd3+))大于5∶1,振荡时间30 min,反应温度20℃时,本体系在HCl,HNO_(3)介质中的萃取率均达99.99%。在较大的pH条件下进行萃取,减少了萃取过程中酸的用量,节约了工艺成本;萃取结果揭示了Cl-对稀土离子萃取时存在抑制作用;P204和[P4446][NTf_(2)]之间存在协同萃取的作用;水相浓度低时有机相的粘度出现较大程度下降及[NTf_(2)]-对导电性能的提高的相互作用,增强了Nd3+与有机相的结合能力。The environmental pollution caused by the traditional extraction process is becoming more and more serious,and the sa⁃ponification wastewater produced by the saponification process and the volatile diluent used in extraction are the main ones.Exploring a method that uses non-saponified extraction and uses a non-volatile diluent is conducive to achieving environmental friendliness and conforms to industry development and wide-ranging requirements at local and overseas.In the comprehensive utilization of resources,the recovery of valuable metals in low-concentration wastewater has a lot of research space.Taking the rare earth metal Nd3+as an exam⁃ple,the P204-[P4446][NTf_(2)]ionic liquid system was used for the experiment of non-saponification extraction.In the process,the wa⁃ter phase concentration measurement adopted inductively coupled plasma optical emission spectroscopy(ICP-OES)and inductively coupled plasma mass spectrometry(ICP-MS).The difference in extraction rate and extraction phenomenon of the system in HCl and HNO_(3) media was compared,and the influence factors of HCl and HNO_(3) media on the extraction results were explored.In terms of pH,the relationship between H+concentration and distribution ratio(D)in different media was studied,and the extraction mechanism was tried to be explored;in terms of shaking time,explored the extraction equilibrium time in different media and found the best condi⁃tions;in terms of temperature factors,the optimal extraction temperature was found through thermodynamic experiments in different media,enthalpy change(ΔH)and Gibbs free energy change(ΔG)were calculated by fitting curves to analyze the thermodynamic pro⁃cess.In terms of experiments with different molar ratios(n(P204)∶n(Nd3+)),the conditions of molar ratio(n(P204)∶n(Nd3+))to achieve the best extraction resulted in different media were discussed.In terms of different concentrations of water phases,the extrac⁃tion rules and causes of different concentrations of water phases in different media in

关 键 词：离子液体 萃取 ND 低浓度水相 

分 类 号：O616[理学—无机化学]