【摘要】 离子吸附型稀土浸出液中共存杂质铝的含量随矿床产地和浸取条件而变化,其浓度有时与稀土属于同一数量级,而铝对稀土的分离纯化过程影响严重。因此,稀土与铝的分离具有重要意义。本文研究了伯胺N₁₉₂₃萃取分离稀土与铝的性能,结果表明:N₁₉₂₃-煤油-异辛醇有机相可以从离子吸附型稀土浸出液中直接萃取稀土,而铝及其他低价金属离子留在水相;其分离系数可以达到10⁵。少量进入有机相的铝继续用（NH₄）₂SO₄溶液反洗（O/A=1∶1）,使负载有机相中稀土与铝的比值大大增加,其分离系数随（NH₄）₂SO₄浓度的升高和溶液pH的下降而增大。确定的最佳浓度和pH分别为2%和1。有机相中的稀土经3 mol·L^-1 NH₄Cl溶液反萃（O/A=2∶1）,可以得到浓度大纯度高的稀土溶液;采用c_Al/c_RE=8.443的含铝稀土浸出液,经萃取、洗涤和反萃,可以得到浓度为4.3～13.34 g·L^-1的c_Al/c_RE=0.0023～0.0027的稀土溶液,稀土回收率大于96%。更多还原

【Abstract】 The concentration of aluminum in the ion adsorption rare earth leachate varies with theorigin of the deposit and the leaching conditions, which sometimes is in the same magnitude as that of rare earth, and shows serious effect on the subsequent separation and purification of rare earth. Therefore, it is of great significance to separate rare earth from aluminum. The extraction separation performance of rare earth and aluminum by primary amine N₁₉₂₃ was studied, the results showed that N₁₉₂₃-kerosene-isooctanol organic phase can directly extract rare earths from the leachate of rare earth ions, while keep aluminum and other low valence metal ions remaining in aqueous phase. The separation factor reaches at around 10⁵. The aluminum in extracted organic phase is backwashed with 2% ammonium sulfate and pH value of 1（O/A ratio of 1∶1）, resulting in a great increase of ratio of rare earth to aluminum in the loaded organic phase. It was demonstrated that the separation factor of RE to Al increases with the increase of ammonium sulfate concentration and with the decrease of solution pH value, the optimum concentration and pH were determined to be 2% and 1, respectively. The rare earth in the organic phase was stripped by 3 mol·L^-1 ammonium chloride solution（O/A=2∶1） to obtain a rare earth solution with high purity and high concentration. Fora leachate with c_Al³⁺/c_RE³⁺=8.443, a rare earth solution with c_Al³⁺/c_RE³⁺=0.0023～0.0027 at the concentration of 4.3～13.34 g·L^-1 can be obtained via extracting with N₁₉₂₃, washing with ammonium sulfate solution and striping with ammonium chloride solution, and the recovery rate of rare earth is over 96%.更多还原