低品位离子型稀土矿提取过程优化研究-矿物加工工程专业论文.docxVIP

Abstract Abstract 万方数据 万方数据 Abstract The ionic rare earth ore of our country has been overload mined for a long time, the richer and more accessible deposits of this rare earth resource got mined in priority gradually, which made this resource deplete increasingly, and difficulty of extracting go from bad to worse. In the process of extracting the low grade ionic rare earth ore, with the low leaching rate, serious leaching tailing, high impurity content but low concentration of rare earth ion in leaching solution and difficult formation of crystalline carbonate rare earth, which made the resource can’t be used effectively. In order to solve these problems, this paper select the ionic rare earth ore from Longnan as research subjects, study and optimize its extraction process, and provide guidance for developing and utilizing this mineral resources effectively. Firstly, this paper studied and optimized the leaching process of the low grade ionic rare earth ore, and the results showed that: the capacity of different electrolyte cation exchanging the rare earth ions was on the order of NH4+K+Na+; When the Leaching agent concentration was higher or the flow rate was slower, the leaching rate would be higher; But when the leaching solution pH value was too high or too low, or the moisture content of ore and ore loading level was too high, or the grain size was too small, all these would affect the leaching efficiency of rare earth, and the rare earth leaching rate. The most optimized parameters for the leaching process was determined: raw water rate was about 5%, ore loading height was about 105mm, the mass concentration of ammonium sulfate was 4%(pH=5.8), leaching liquid-solid ratio was 0.8:1, extraction rate was 0.49mL/min, the late top water liquid solid leaching ratio was 0.05:1, the leaching solution can be obtained with leaching rate of 93.88% and concentration of 1.61g/L; Analysising the infrared spectrum leaching residue, we can know that after the role