| abstract |
A process for pretreating organic extractants and its product and application in SX separation of rare earth. The pretreating method is that extractant and rare earth solution are mixed with powder or slurry of alkaline earth metal compound containing magnesium and/or calcium to realize pre-extraction, or the organic extractant are mixed with rare earth carbonate slurry to realize pre-extraction. When rare earth ion in aqueous phase is extracted into organic phase, the exchanged hydrogen ions enter into aqueous phase and dissolve the alkaline earth metal compound or the rare earth carbonate which helps to keep the acidity equilibrium of the system. The obtained organic extractant loaded with rare earth is used for unsaponificated SX separation of rare earth. n With this method, there is no need to saponificate organic extractant with liquid ammonia or alkali, and there is no ammonia-nitrogen wastewater produced. So separation cost decrease at a large scale and a lot of the cost to treat the three wastes is cut. This method is applicable to SX separation for all rare earth elements in chloride, sulphate and nitrate system and has advantages of low investment and high profit. |