Determination of FeCl-4 in organic phase of tributyl phosphate for lithium extraction by ultraviolet-visible spectrophotometry
SHI Zhihui1, LIU Jie*1, JIA Minghui1, LI Jincheng1, SONG Chaoqian1, HUANG Kun2
1. School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, China; 2. School of Metallurgical and Ecological Engineering, University of Science & Technology Beijing, Beijing 100083, China
Abstract：The direct and accurate determination of Fe content in the complex state of HFeCl4·2TBP in the tributyl phosphate (TBP)/kerosene organic phase is of great significance for enhancing the extraction efficiency of lithium from salt lake brine and improving the extraction process. In the experiment, FeCl3·6H2O solid was dissolved in hydrochloric acid with different concentrations. The absorption wavelength of FeCl-4 in organic phase was measured by ultraviolet-visible (UV-Vis) spectrophotometry, and the maximum absorption wavelength at 363 nm was determined. The experimental conditions were optimized. The results showed that the Fe in organic phase was in the state of FeCl-4 when FeCl3·6H2O solid was dissolved with 12 mol/L hydrochloric acid. Under the optimized conditions, the standard solutions of organic phase containing FeCl-4 with different concentrations were prepared. The absorbance was determined by UV-Vis spectrophotometry at the wavelength of 363 nm, and the calibration curve was plotted. The absorbance was linear to the corresponding mass concentration of Fe in range of 0-17.8 mg/L. The correlation coefficient was 0.995 6. The apparent molar absorption absorptivity was ε=1.27×104 L/mol. The limit of detection was 0.12 mg/L. The content of iron in the form of FeCl-4 in TBP/kerosene organic phase was determined according to the experimental method. The relative standard deviations (RSD, n=6) of determination results were between 0.43% and 0.64%. The spiked recoveries were between 100.10% and 100.48%.
石志慧, 刘杰, 贾明辉, 李金成, 宋超前, 黄焜. 紫外可见分光光度法测定磷酸三丁酯萃锂有机相中FeCl—4[J]. 冶金分析, 2021, 41(8): 91-95.
SHI Zhihui, LIU Jie, JIA Minghui, LI Jincheng, SONG Chaoqian, HUANG Kun. Determination of FeCl-4 in organic phase of tributyl phosphate for lithium extraction by ultraviolet-visible spectrophotometry. , 2021, 41(8): 91-95.
[1] 张燕辉,李丽娟,李晋峰,等.磷酸三丁酯从盐湖卤水中萃取锂的机理研究[J].无机盐工业,2012,44(3): 12-15. ZHANG Yanhui, LI Lijuan, LI Jinfeng, et al. Study on mechanism of extraction of lithium from salt lake brine by tributylphosphate[J].Inorganic Chemistry Industry,2012,44(3):12-15. [2] Song Jianfeng,Huang TAO,Qiu Hongbin,et al. Recovery of lithium from salt lake brine of high Mg/Li ratio using Na[FeCl4*2TBP] as extractant:Thermodynamics, kinetics and processes[J].Hydrometallurgy,2017,173:63-70. [3] 李琴,彭仁文,郑群珍,等.一种9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物中的铁含量的测定方法: CN105092499A[P].2015-09-17. [4] 徐晓华,刘晓庆.火焰原子吸收光谱法测定紫菜中忒铁含量的方法: CN103528879A[P].2013-09-26. [5] 孙登明,刘俊英,阮大文.萃取催化动力学光度法测定痕量铁[J].分析化学,1998,26(2):196-199. SUN Dengming,LIU Junying,YUAN Dawen.Determination of trace iron by extraction catalytic kinetic spectrophotometry[J]. CIESC Journal, 1998, 26(2): 196-199. [6] 成勇. ICP-AES测定钛合金中硅钒铁铝镍钼铬[J].稀有金属材料与工程,2012,41(10):183-186. CHENG Yong.Determination of the silicon, vanadium, iron, aluminum, nickel, molybdenum and chromium in titanium alloy by ICP-AES[J]. Rare Metal Materials and Engineering,2012,41(10):183-186. [7] 王征,赵学玒,孙传强,等.电感耦合等离子体质谱法测定痕量铁元素时碰撞反应池条件的探讨[J].冶金分析, 2015, 35(6):1-7. WANG Zheng, ZHAO Xuehong, SUN Chuanqiang, et al. Discussion on collision/recation cell condition for determination of trace iron by inductively coupled plasma mass spectrometry[J]. Metallurgical Analysis,2015,35(6):1-7. [8] 吴雪英,魏雅娟,刘晓玲,等. EDTA滴定法测定再生锌原料中铁[J].冶金分析,2016,36(5): 53-57. WU Xueying, WEI Yajuan, LIU Xiaoling, et al. Determination of iron in regenerated zinc raw material by EDTA titration method[J]. Metallurgical Analysis,2016,36(5):53-57. [9] 李国强,杨建君,何家洪,等.分光光度法测定铁(Ⅲ)的研究进展[J].冶金分析,2014,34(1):34-44. LI Guoqiang,YANG Jianjun,HE Jiahong, et al. Review of the research on the determination of trace Fe(III) with spectrophotometry[J].Metallurgical Analysis,2014,34(1):34-44. [10] 邢曼钰. P204-煤油有机相中微量铁的直接测定[J].冶金分析,1982,2(5): 36-37. XING Manyu. Direct determination of trace iron in the organic phase of P204-kerosene[J].Metallurgical Analysis, 1982,2(5): 36-37.
