Study on alkali mechanical activation for recovering rare earth from waste fluorescent lamps

作     者：Ling He Wen Ji Yanwei Yin Weimin Sun 

作者机构：State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and EngineeringLanzhou University of Technology 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2018年第36卷第1期

页      面：108-112页

核心收录：

学科分类：0806[工学-冶金工程] 08[工学] 

基　　金：Project supported by the State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of Technology(SKLAB02014010) the National Natural Science Foundation of China(516744130) Natural Science Fund of Gansu Province of China(1508RJZA049) 

主　　题：Rare earthSpinel structureRecovery rateAlkali mechanical activationWaste phosphorsRare earths 

摘      要：Recycling of rare earth from waste fluorescent lamps is becoming increasingly important in future sustainable development. However, cerium and terbium are usually difficult to recover due to the stable spinel structure. In the research, alkali mechanical activation was innovatively used to pretreat the waste phosphors for recovering rare earths. The effect of alkali mechanical activation on the structural changes of waste phosphors was explored using X-ray diffraction （XRD） and Fourier transform infrared spec- troscopy （FFIR）. Meanwhile, the effects of different parameters including milling speed, activation time, and amount of alkali on the leaching rates of rare earth were investigated. The rare earth elements re- covery rates are observed to increase rapidly, particularly with increases in rotational speed and acti- vation time. Under optimal conditions, the maximum leaching rates of Ce and Tb reach 85.0% and 89.8%, respectively. And the total recovery rates of rare earth reach 95.2%. All the results indicate that alkali mechanical activation can effectively destroy the spinel structure and produce substantial physico- chemical changes. These changes lead to the easy dissolution of rare earths in acid solution, and greatly improve the leaching of cerium and terbium.