Solvent extraction of La（III） with 2-ethylhexyl phosphoric acid-2-ethylhexyl ester （EHEHPA） by membrane dispersion micro-extractor

• Published in: 中国稀土学报：英文版 2013, Vol.31 (11), p.1114-1118
• Main Author: 侯海龙 王运东 徐建鸿 陈晋南
• Format: Article
• Language: English
• Subjects: EHEHPA; La（Ⅲ）; 乙基己基磷酸; 乙基己酯; 提取效率; 最佳操作条件; 溶剂萃取; 膜分散
• ISSN: 1002-0721; 2509-4963

The conventional rare earth solvent extraction equipments have many problems such as long mixing time, low processing capacity, large factory area occupation, high energy consumption and so on. In order to solve the problems, many types of equipments were brought out. In this work, studies were carried out on the La（III） extraction process with 2-ethylhexyl phosphoric acid-2-ethylhexyl ester （EHEHPA） by membrane dispersion micro-extractor. Equilibrium studies showed that the initial aqueous pH value 4.15 with the saponification rate 40%was the optimal operation condition. The effects of membrane dispersion micro-extractor operational conditions such as dispersion mode, bulk flow rate and organic phase flow rate on the extraction efficiency were studied. The results showed that when the organic solution was the dispersed phase, the extraction efficiency was higher than that of others. Increasing bulk flow ratio could enhance the extraction efficiency greatly. When the ratio of organic phase flow rate to that of aque-ous phase was 80：80, the extraction efficiency was over 95%. The effect of stripping phase acidity on the La（III） recovery was studied. The results showed that when the stripping phase pH was 2.0, organic phase flow rate to stripping phase flow rate was 20：80;the re-covery efficiency of La（III） can reach 82%.