(1. 内蒙古科技大学 材料与冶金学院 内蒙古自治区稀土现代冶金新技术与应用重点实验室，包头 014010；
2. 北京化工大学 材料科学与工程学院，北京 100029)
摘 要: 根据Al3+与F-能形成稳定的络合离子[AlF6]3-，采用HNO3-Al(NO3)3溶液络合浸出包头稀土精矿中的氟元素。讨论HNO3浓度、Al(NO3)3浓度、液固比、搅拌速度、温度和搅拌时间等工艺条件对氟浸出的影响。结果表明：在HNO3浓度为3 mol/L、Al(NO3)3 浓度为1.5 mol/L、液固比(mL/g)为30:1、搅拌速度为300 r/min、温度为100 ℃、搅拌时间为90 min的条件下，稀土精矿中氟浸出率达到97.59%，从而使氟碳铈矿进入溶液中，达到与独居石分离的目的。F-与Al3+的络合机理研究表明：F-与Al3+能形成配位数是1~6的复杂稳定配合物，并随着氟铝比的增大，氯铝配合物向高配位方向移动。
关键字: 稀土精矿；HNO3-Al(NO3)3；氟；络合；浸出
（1. School of Materials and Metallurgy, Inner Mongolia Autonomous Region Key Laboratory of New Technologies of Modern Metallurgy and Application of Rare Earth Materials, Inner Mongolia University of Science and Technology, Baotou 014010, China;
2. College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China）
Abstract:According to the reaction of Al3+ with F- to form stable coordination ion [AlF6]3-, HNO3-Al(NO3)3 was used as a coordination agent to leach the fluorine from Baotou rare earth concentrate. The effects of different parameters including HNO3 concentration, Al(NO3)3 concentration, liquid to solid ratio, stirring speed, temperature and stirring time, on the leaching of fluorine element, were investigated. The results show that the fluorine leaching rate of rare earth concentrate is 97.59% when the HNO3 concentration is 3 mol/L, Al(NO3)3 concentration is 1.5 mol/L, liquid-solid ratio(mg/L) is 30:1, stirring speed is 300 r/min, temperature is 100 ℃ and stirring time is 90 min. And under this condition, the bastnaesite in the solution is separated from monazite. Besides, the coordination mechanism of F- and Al3+ was studied, and the results show that 1 mol Al3+ can coordinate with 1-6 mol F-, and complex moves to the direction of high coordination with the increase of fluoride concentration.
Key words: rare earth concentrate; HNO3-Al(NO3)3; fluorine element; coordination; leaching
