Extraction And Recovery Of Cerium(Ⅳ), Phosphate And Fluorine From Baotou Ore Sulfuric Solution Using Cyanex923

Baotou mixed ores is one of the main light RE ores in China, which is dominantly composed of bastnasite(REFCO3) and monazite(REPO4) assembly. A series of problems accured during the processing of Baotou mixed ores, such as environmental pollution and resources wasting. Aiming at solving these problems, the solvent extraction method was adopted in extractant Cyanex923 of high tetravalent cerium selection, studying under different experimental conditions for the extraction and recovery situation of Baotou rare earth concentrate of cerium, fluorine and phosphorus in the simulation liquid:(1) Changing extraction liquid acidity, salt ion concentration and extractant concentration to study for the extraction of tetravalent cerium using Cyanex923 in the solution;(2) Changing temperature of the extraction system and calculating thermodynamic parameters, the extraction system is an exothermic reaction, high temperature is not conducive to the extraction reaction;(3) Comparing of Ce(Ⅳ), Ce(Ⅲ) and Th(Ⅳ) extraction, Cyanex923 was able to separate the tetravalent cerium from the solution;(4) The extraction using Cyanex923 was significantly better than other extractants with comparison of different extraction agents on the Ce(Ⅳ) extraction;(5) For stripping of extraction system, the effect of acidity on stripping was investigated and stripping particles were characterized;(6) Synergistic extraction of Ce(Ⅳ) using Cyanex923 with P507, P204 and ionic liquid were studied, it was found that only Cyanex923+[A336][P507] synergistic extraction of Ce(Ⅳ) showed synergistic effect.Extraction in Baotou rare earth concentrate of sulfuric leaching liquor using Cyanex923 was also investigated and generated reverse micelles in extraction process, using the method of reduction stripping to obtained particles, analyzing and characterizing by XRD and SEM. The main component of stripping particles was cerium, fluorine and phosphorus. The results showed that solvent extraction method can recycle cerium, fluoride and phosphate from the leaching liquor, thus reducing the environmental pollution and resources wasting.