(1. 江西理工大學 冶金與化學工程學院，贛州 341000；
2. 河南省冶金研究所有限責任公司，鄭州 450053)
摘 要: 針對離子吸附型稀土礦浸出液中鋁元素含量高、對稀土后續(xù)分離影響大的問題，本研究以3,5-二硝基水楊酸(DNS)作為有機配體，以硅膠作為基體材料，通過化學合成3,5-二硝基水楊酸化學鍵合硅膠進行吸附除鋁研究。結果表明：當3,5-二硝基水楊酸與Al3+的配位比為1:1、溶液pH=3.5、3,5-二硝基水楊酸改性硅膠用量為2 g時，溶液中Al3+去除率達90%以上，稀土幾乎無損失。采用紫外吸收的方法對機理進行研究，結果顯示稀土料液中的Al3+通過取代3,5-二硝基水楊酸分子中羥基上的H+與其形成絡合物，進而實現(xiàn)稀土與鋁的分離。由吸附動力學研究可知，3,5-二硝基水楊酸改性硅膠對Al3+的吸附符合二級吸附動力學模型，其R2為0.98813。
關鍵字: 稀土；除鋁；3,5-二硝基水楊酸；改性硅膠；選擇性配位
（1. School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China;
2. Henan Institute of Metallurgy Co., Ltd., Zhengzhou 450053, China）
Abstract:In view of the high content of aluminum in leaching solution obtained by ion-adsorption rare earth mining and the great influence on the subsequent separation of rare earths, silica gel as the basic material was modified with 3,5-dinitrosalicylic acid (DNS) as the organic ligand through chemical synthesis, which was used for adsorption and aluminum removal from leaching solution of RE. The results show that when the coordination ratio of 3,5-dinitrosalicylic acid to Al3+ is 1:1 , the solution pH value is 3.5 and the amount of the modified silica gel with DNS is 2 g, the Al3+ removal rate is over 90%, and the RE loss is 0% nearly. The results of UV spectrum analysis show that Al3+ can form a complex through replacing of H+ on the hydroxyl group of the DNS, which achieves the separation of Al3+ and RE3+. According to the study of adsorption kinetics, the adsorption of aluminum ions by modified silica gel with DNS conforms to the second-order adsorption kinetics model, and its R2 is 0.98813.
Key words: rare earth; aluminum removal; 3,5-dinitrosalicylic acid; modified silica gel; selective coordination
