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The conventional rare earth solvent extraction equipmentshave many problems,such as long mixing time,low processing capacity,large factory area occupation and so on.In order to solve these problems,many types of equipments and methods were studied e.g.the hollow fiber membrane extractor[1,2],the extraction column[3],liquid surfactant membranes extractor[4,5],the ionic liquid[6,7],and the ion exchange resin[8] etc.Hitherto,there is no report on the rare earth elements extraction by the membrane dispersion micro-extractor.In this paper,we have studied the La (III) solvent extraction process with 2-ethylhexyl phosphoric acid-2-ethylhexyl ester (EHEHPA) by membrane dispersion micro-extractor.Equilibrium studies show that the initial aqueous pH value of 4.15 and the saponification rate of 40% were the optimal operational conditions.The effects of membrane dispersion micro-extractor operational conditions,such as dispersion mode,bulk flow rate,flow ratio,and stage number on the extraction efficiency were studied.The results show that when the organic solution is the dispersion phase,the extraction efficiency is higher.Increasing flow ratio and stage number can enhance the extraction efficiency greatly.The highest extraction efficiency is 94%.