RECOVERING RE FROM LEACHING LIQUOR OF RARE EARTH ORE BY EXTRACTION
(Institute of Nuclear Energy Technolegy; Tsinghua University; Beijing 100084)
Abstract: The extractive process for the production of rare earth chlorides from leaching liquor of some rare erth ores has been studied with organic phosphoric acid as extractive reagent.The feasibility of extractive technology has been confirmed in unitized experiment with a d 20cm centrifugal extractor.When leaching liquor was adjusted to pH=5 with ammonia-sodium sulfide,the heavy metal ions and 90% aluminum ion were removed,and purified liquor was obtained.Rare earth recovery rate was more 90% through two stages countercurrent extraction of purified liquor and three stages countercurrent stripping of organic phase loading rare earth with 6mol/L HCl.Rare earth concentration of stripped liquor was above REO 150g/L,and solid RECl3 that equivalently contained 45% to 46% REO was obtained through vaporization.
Key words: rare earth ore; leaching; solvent extraction