Impurity removal method for low-grade rare earth sulfate leachate

The invention discloses an impurity removal method for low-grade rare earth sulfate leachate. The method comprises the following steps that firstly, lime powder is added into the rare earth sulfate leachate under stirring, and adding of the lime powder is stopped after the pH value of the rare earth sulfate leachate reaches 1.5-2.0; secondly, magnesium oxide slurry is slowly added at the speed of4mL/min, and adding of the magnesium oxide slurry is stopped after the pH value reaches 4.5-5.5; and thirdly, the mixture is continuously stirred for 30min and clarified for 2h to obtain a precipitation solution A, suction filtration is conducted on the precipitation solution A to separate and remove precipitates, and a rare earth sulfate solution is obtained. According to the method, impurities in the low-grade rare earth sulfate leachate can be effectively removed, the cost is saved, and the environmental pollution is reduced. 本发明公开了一种低品位硫酸稀土浸出液的除杂方法，其是在搅拌的情况下，先向硫酸稀土浸出液中加入石灰粉，使硫酸稀土浸出液的pH值达到1.5～2.0后停止加入石灰粉，然后再以4mL/mi