(江西理工大学 冶金与化学工程学院，赣州 341000)
摘 要: 提出将抗坏血酸应用到离子吸附型稀土矿的浸取过程，通过其与稀土的络合作用来强化离子相稀土的浸取，降低浸取剂用量，减少氨氮污染；同时，利用抗坏血酸的还原性质浸取离子吸附型稀土矿中的胶态相稀土，提高稀土资源利用率。以硫酸铵-抗坏血酸为复合浸取剂，对不同浸取条件下稀土及铁铝杂质的浸出行为进行研究。结果表明：在最佳浸取条件下，即硫酸铵浓度0.15 mol/L、抗坏血酸浓度为1.0 g/L、浸取剂pH为2.5、浸取剂体积为200 mL、注液速度为0.80 mL/min时，稀土浸出率达102.2%，铈配分为5.37%，浸出液中铁和铝的浓度分别为20.91 mg/L和23.74 mg/L。此外，复合浸取体系中离子相稀土的浸出率为98.7%，较单独硫酸铵浸取体系提高2.7%，其在浸取尾矿中的含量仅为2×10-5；而胶态相稀土的浸出率达42.9%，其在尾矿中的含量为8×10-5。离子吸附型稀土矿抗坏血酸强化-还原浸取技术具有有效提高稀土资源利用率和减少环境氨氮污染的双重优势，对离子吸附型稀土矿高效绿色开发及其健康可持续发展具有重要推动作用。
关键字: 离子吸附型稀土矿；抗坏血酸；强化；还原；胶态相稀土
（School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China）
Abstract:The application of ascorbic acid to the leaching process of the ion-adsorption type rare earths ore was proposed. The ascorbic acid can form a stable coordination with rare earth ions, so that it would intense the leaching of ion-exchangeable phase rare earth, resulting in the decrease of the leaching agent dosage and ammonia nitrogen pollution. Moreover, the ascorbic acid has a strong reductive property, it can leach the colloidal sediment phase rare earth, improve the utilization of the rare earth resources. The ammonium sulfate and ascorbic acid were used as a compound leaching agent, the leaching behaviors of rare earth and Fe/Al impurities under different leaching conditions were studied. The results show that 102.2% of the total rare earth leaching efficiency and 5.37% Ce partition are achieved under the optimum leaching condition in a flow rate of 0.80 mL/min, initial pH of 2.5, leaching agent of 200 mL, ammonium sulfate of 0.15 mol/L and ascorbic acid of 1.0 g/L in the leaching agent. The concentration of Al is 23.74 mg/L and the concentration of Fe is 20.91 mg/L in the leaching liquor. Additionally, in the ammonium sulfate-ascorbic acid compound leaching system, the leaching efficiency of ions-exchangeable phase rare earth is 98.7%, which is 2.7% higher than that in the ammonium sulfate leaching system, and the content of the ion-exchangeable phase rare earth in the leaching tailings is only 2×10-5. The leaching efficiency of colloidal sediment phase rare earth is about 42.9% and the colloidal sediment phase rare earth is 6×10-5 in the leaching tailings. The intensification-reduction leaching technology of the ion-adsorption type rare earths ore with ascorbic acid has the dual advantages of improving the utilization of rare earth resources and the reduction of ammonia nitrogen pollution. It plays an important role in the efficient-green development of the ion-adsorption type rare earths ore and their healthy and sustainable development.
Key words: ion-adsorption type rare earths ore; ascorbic acid; intensification; reduction; colloidal sediment phase rare earth
