| Baotou Baiyunebo Mine is a large-scale multi-metal mine, mainly including Fe, Nb and RE. The properties of the ore are very complicated. As we know, there are about 6 million tons of tailings per year from Baotou Mineral Processing Plant, including high intensity magnetic tailings and rare earths flotation tailings. Each year, there are about 0.238 million tons of REO will loss along with the high intensity magnetic tailings. But at present, the recovery rate of rare earths in the symbiotic mine is only about 10%, and most of the rare earths and Th,U enter into tailings of Bao Steel'Concentrator, the grade of rare earths and Th,U in the tailings are slightly higher than the grade of rare earths in run-of-mine ore and the value is considerable. In order to increase the comprehensive utilization ratio of Baiyunebo's resources, it is necessary to do some research on rare earths recovery.In this paper, Baiyunebo tailings was used as a raw material to investigate the carbochl-orination reaction, inspecting the chloride rates of scandium, thorium, uranium at the different reaction temperatures and times. The results showed that:The all chloride rates of scandium, thorium, uranium were increase with the increasing of temperature at 2 h, from 400℃to 600℃, and the chloride rates of scandium, thorium, uranium had a leap at 500℃to 600℃. In reaction time was 1 h,2 h and 4 h, reaction temperature was 500℃, the chloride rates of scandium, thorium, uranium were not high, their respective chloride rate had reached a higher level in 600℃, They reach a the basic balance at 2 h.The tailings of Bao Steel's Concentrator was used as a raw material to investigate the carbochlorination reaction with SiCl4 as defluorination agent. The influences of reaction time and reaction temperature on the carbochlorination reaction were investigated. The results showed that the optimum reaction time was 2 h. Between 700℃and 800℃, the all chloride yield of Sc, Th, U were above 80%.In this paper, sodium carbonate was used as de-fluorination agent. Mixtures were roasted at high temperature, making rare earths fluoride carbonate and rare earths phosphate reacted with sodium carbonate to form rare earths oxides and rare earths phosphate-soluble salt. We studied the conversion percent of scandium. Thorium and uranium which first treated with sodium carbonate roasting before carbochlorination. All of chloride rates of scandium, thorium, uranium increased as the increase of temperature, It had reached 75 percent at 800℃, So, this method had a certain value. XRD analysis showed that the residue obtained between 450℃and 500℃involved SiO2, Fe2O3, monazite and rare earth fluorides, between 700℃and 800℃involved SiO2 and monazite.Finally, we extracted Sc with TBP from the water obtained after chlorination and baking-chlorination. The minerals after roasting chloride and carbochlorination, dissolved with water change PH value to precipitate uranium, thorium, and then leaching thorium, uranium with ni tric acid, at last extracted uranium, thorium with different concentrations of TBP. According to the results:the extraction rate of Sc can reach 85 percent, that was of high value. The extraction rate of thorium and uranium were 40% and 55%. The results showed that chlorinate the tailings with low content of thorium, uranium, scandium first after the extraction process was feasible.
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