Study of leaching behaviors of main materials in ionic rare earth ore

The leaching behaviors of water， RE， ammonium sulfate and other foreign ions were investigated by using the column leaching method with the leaching agent of ammonium sulfate. The results show that ionic rare earth ore has relatively strong adsorption for water which made the contents of water increased from 17.74 % to 33.7 %. The leaching rate of RE is 99.98 %. For impurities ,the leaching amounts of the Al³⁺ is relatively large, the SiO₃^2- is smaller, but the Fe³⁺ is almost no leaching and the leaching order of the ions is followed as SiO₃^2-, RE³⁺, Al³⁺, Fe³⁺. When the concentration of Al3+ and Fe3+ reach to the peak, the lowest pH value of the leachate is obtained. However, with the addition of the leaching agent and water, the pH value are raised up, until run up to the pH value of the ammonium sulfate solution and the water.