Matrix Separation-Determination of Rare Earth Oxides in Bauxite by
Inductively Coupled Plasma-Atomic Emission Spectrometry
HU Xuan1, CHENG Zi-hui1*, ZHANG Shu-chao2, SHI Lei2
1. Guobiao (Beijing) Testing & Certification Co., Ltd., Beijing 100088, China
2. China National Quality Supervision and Inspection Center for Light Metal, Zhengzhou 450041, China
Abstract：Extracting rare earth elements from hematite and developing high-value-added products can improve the comprehensive utilization of mineral resources, inject resources into enterprises and promote the development of high and new technology. The content of rare earth oxides in red mud is low (0.001 0 %~0.050%), and there are many matrix elements such as aluminum and iron in red mud. How to eliminate the interference of matrix elements in the determination of rare earth oxides is important. The traditional acid dissolving methods can cause incomplete digestion of some elements, which are difficult to quantify accurately and has a low recovery rate. In contrast, the alkali fusion methods can introduce a large amount of alkali flux and cause serious matrix interferences, also block the atomizer at the same time. Red mud was melted with sodium hydroxide and extracted with hot water. Triethanolamine solution was used to eliminate the matrix interferences of aluminum and iron, EDTA disodium solution was used to complex with calcium, magnesium and other interfering elements, and rare earth hydroxide was retained in the precipitation, precipitation was dissolved into the liquid to be tested by hydrochloric acid. Thus rare earth elements were separated from fluxes and matrix elements. The experiment showed that the standard solution did not need matrix matching, the linear correlation coefficients of the calibration curve were not smaller than 0.999 9, and the detection limits were 0.000 2%~0.001 5%. The relative standard deviations of rare earth oxides in the sample were between 2.5% and 7.2%, recovery rates were between 85.0% and 105.0%; results of inductively coupled plasma mass spectrometry (ICP-MS) were consistent with that of ICP-OES. ICP-OES realized the analysis of rare earth oxides in red mud in the future.
[1] LI Bin, WANG Zhi-ping, QU Fan, et al(李 彬, 王枝平, 曲 凡, 等). Journal of Kunming University of Science and Technology·Natural Science(昆明理工大学学报·自然科学版), 2019, 44(2): 1.
[2] WANG Bao-lei, WU Yu-feng, ZHANG Qi-jun, et al(王宝磊, 吴玉锋, 章启军, 等). Chinese Rare Earths(稀土), 2016, 37(5): 92.
[3] HU Shan-ling, QIU Jin, WU Zhi-fang, et al(胡珊玲, 邱 谨, 吴志芳, 等). Metallurgical Analysis(冶金分析), 2016, 36(10): 85.
[4] SUN Zhi-feng, ZHANG Zhi-gang, ZHANG Yi-ming, et al(孙志峰, 张志刚, 张翼明, 等). Chinese Rare Earths(稀土), 2010, 31(1): 77.
[5] Nuchdang S, Injarean U, Rattanaphra D. International Nuclear Science and Technology Conference, 2019.
[6] PAN Chun-xiu, WANG Wei, LI De-jun, et al(潘春秀, 王 伟, 李德军, 等). Physical Testing and Chemical Analysis Part B: Chemical Analysis(理化检验-化学分册), 2019, 55(2): 227.
[7] ZHANG Wen-juan, XIE Ling-jun, LIU Hong(张文娟, 谢玲君, 刘 鸿). Nonferrous Metals Science and Engineering(有色金属科学与工程), 2016, 7(6): 141.
[8] SONG Xun-dong, FAN Xiao-wei, CHEN Wen, et al(宋旭东, 樊小伟, 陈 文, 等). Metallurgical Analysis(冶金分析), 2018, 38(6): 19.
[9] DONG Xue-lin, HE Hai-yang, CHU Qin, et al(董学林, 何海洋, 储 溱, 等). Rock and Mineral Analysis(岩矿测试), 2019, 38(6): 620.
[10] Satyanarayanan M, Balaram V, Sawant S S, et al. Atomic Spectroscopy, 2018, 39(1): 1.
[11] YUAN Jing, SHEN Jia-lin, LIU Jian-kun, et al(袁 静, 沈加林, 刘建坤, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2018, 38(2): 582.
[12] JIANG Tian-yi, WU Wen-qi, ZHANG Shu-jie, et al(蒋天怡, 吴文琪, 张术杰, 等). Metallurgical Analysis(冶金分析), 2017, 37(12): 27.
[13] MEN Qian-ni, SHEN Ping, GAN Li-ming, et al(门倩妮, 沈 平, 甘黎明, 等). Rock and Mineral Analysis(岩矿测试), 2020, 39(1): 59.
[14] HU Xuan, LIU Wan-chao, SHI Lei(胡 璇, 刘万超, 石 磊). Physical Testing and Chemical Analysis Part B: Chemical Analysis(理化检验：化学分册), 2017, 53(11): 1304.
