离子型稀土浸出液复合钠盐高效富集稀土

High Efficient Enrichment of Rare Earth in Ionic Rare Earth Leachate with Complex Sodium Salt

为实现无铵富集稀土,以复合钠盐为沉淀剂,对铝盐体系离子型稀土矿浸出液中稀土进行富集。考察了pH对稀土浸出液除铝效果的影响,研究了不同沉淀剂、沉淀剂配比及用量、终点pH、反应温度、反应时间、陈化时间对稀土沉淀率的影响。结果表明,在初始稀土浓度0.014 64 mol/L、铝浓度0.54 g/L、初始pH=3.89、反应温度25℃、反应时间60 min的条件下,除铝终点pH=4.93时,残余铝浓度为13.02 mg/L,稀土损失为1.2%;当复合沉淀剂用量为0.7倍理论量的70%NaHCO_(3)+30%Na_(2)CO_(3)、沉淀终点pH=6.72、反应时间60 min、反应温度25℃、陈化时间40 min时,稀土沉淀率高达99.68%,灼烧后氧化稀土总量为96.48%,铝含量为0.52%。

In order to achieve non-ammonium enrichment of rare earth,complex sodium salt was used as precipitant to enrich rare earth in leachate of ion-type rare earth ore in aluminum salt system.Effect of pH value on removal of aluminum from rare earth leachate was investigated,and effects of different precipitators,ratio and dosage of precipitators,pH value at end point,reaction temperature,reaction time,and aging time on precipitation rate of rare earth were studied.The results show that residual aluminum concentration is 13.02 mg L,and rare earth loss is 1.2%under the conditions including initial rare earth concentration of 0.01464 mol L,aluminum concentration of 0.54 g L,initial pH value of 3.89,reaction temperature of 25℃,reaction time of 60 min,and pH value at end point of 4.93.When the complex precipitator is 70%NaHCO_(3)+30%Na_(2) CO_(3) of 0.7 time of the theoretical amount,end point pH value of precipitation is 6.72,reaction time is 60 min,reaction temperature is 25℃,and aging time is 40 min,the rare earth precipitation rate is 99.68%,total amount of rare earth in rare earth oxide is 96.48%,and aluminum content is 0.52%.