Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou, 341000, PR China.
Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou, 341000, PR China; CAS Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, PR China; Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials, Fujian Research Center for Rare Earth Engineering Technology, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen, Fujian, 361021, PR China.
J Environ Manage. 2022 May 15;310:114743. doi: 10.1016/j.jenvman.2022.114743. Epub 2022 Feb 22.
Due to the complex composition of ion-adsorbed type rare earth ore leaching solution, there are challenges in the process of rare earth (RE) separation, such as large RE loss rate, low product purity, radioactive residue and so on. In this article, 8-hydroxyquinoline modified silica gel (HQ-SiO) and 2,2'-(1,4-phenylenebis(oxy)) dioctanoic acid (PPBOA) were used to form an efficient process for impurities removal and RE enrichment. Solid phase extraction successfully intercepted 96.7% of the radioactive element thorium. The concentration of aluminium was reduced to 2.14 ppm by frank chromatography. Rare earth elements were enriched from 336.35 mg/L to 237.75 g/L by extraction-precipitation, that is, the enrichment multiple reached more than 700 and the proportion of RE was increased from 21.85% to 96.62%. The loss rate of RE was controlled below 1.59%. Moreover, the magnesium salt leaching solution could be recycled for the leaching of RE ores. Although some liquid waste need to be treated in the processes of HQ-SiO production and regeneration, the integrated process helps to decrease volatile organic solvent, acid-base consumption, wastewater and waste residue. It is an environment-friendly RE enrichment and impurity removal process, which shows application potential in the production field of ion-adsorbed type rare earth mineral products.
由于离子吸附型稀土矿浸出液成分复杂，在稀土（RE）分离过程中存在稀土损失率大、产品纯度低、放射性废渣等问题。本文采用 8-羟基喹啉改性硅胶（HQ-SiO）和 2,2'-(1,4-亚苯基双（氧）)二辛二酸（PPBOA）形成一种高效去除杂质和富集稀土的工艺。固相萃取成功截留了 96.7%的放射性元素钍。通过正相色谱法将铝的浓度降低至 2.14 ppm。通过萃取-沉淀，将稀土元素从 336.35 mg/L 富集到 237.75 g/L，即富集倍数达到 700 倍以上，RE 比例从 21.85%提高到 96.62%。RE 的损失率控制在 1.59%以下。此外，镁盐浸出液可回收用于浸出稀土矿石。虽然 HQ-SiO 生产和再生过程中需要处理一些废液，但该综合工艺有助于减少挥发性有机溶剂、酸碱消耗、废水和废渣。这是一种环保的稀土富集和杂质去除工艺，在离子吸附型稀土矿物产品的生产领域具有应用潜力。
