Determination of cobalt,copper,iron,manganese,calcium, magnesium and aluminum in crude cobalt hydroxide by energy dispersive X-ray fluorescence spectrometry with powder pellet preparation
LAN Fuyin, MENG Wenfei, LIU Jie, ZHOU Kuanda, LU Zhiguo
La Sino-Congolaise Des Mines S.A.,Beijing 100039,China
Abstract：The main chemical components of crude cobalt hydroxide include cobalt, copper, iron, manganese, calcium, magnesium and aluminum, and their contents are decisive indicators to determine the grade of crude cobalt hydroxide. Energy dispersive X-ray fluorescence spectrometry (ED-XRF) could be used to replace the chemical wet method to determine the contents of cobalt, copper, iron, manganese, calcium, magnesium, and aluminum in crude cobalt hydroxide, which could shorten the analysis cycle and achieve simultaneous and rapid determination of each element. The powder pellet preparation was conducted. After the sample was ground to 74 μm and boric acid was used as the binder base edge, the sample was pressed into a smooth and flat specimen with pressure of 10 s at 15 t. 16 crude cobalt hydroxide production samples with certain gradient in concentration of each element, which could cover the content range of each element in crude cobalt hydroxide, were selected as the calibration sample series to plot the calibration curves. The contents of these elements in calibration sample series were determined by industry standard of YS/T 1157-2016. The empirical coefficient method was adopted for matrix correction. A method for rapid determination of cobalt, copper, iron, manganese, calcium, magnesium, and aluminum in crude cobalt hydroxide by ED-XRF was established. The linear correlation coefficients of the calibration curves for these elements were all greater than 0.998. The detection limits of this method were in range of 0.001 4%-0.093%. The same cobalt hydroxide sample was used for precision tests according to the proposed method. The relative standard deviations (RSD, n=11) of determination results for these elements were between 0.11% and 3.9%. In addition, 4 crude cobalt hydroxide samples from non-calibration series were selected and determined according to the proposed method as well as industrial standard of YS/T 1157-2016. The difference of the two methods could meet the reproducibility limit requirements specified in industrial standard of YS/T 1157-2016.
兰福荫, 蒙文飞, 刘杰, 周宽达, 陆智国. 粉末压片-能量色散X射线荧光光谱法测定粗制氢氧化钴中钴铜铁锰钙镁铝[J]. 冶金分析, 2024, 44(3): 30-35.
LAN Fuyin, MENG Wenfei, LIU Jie, ZHOU Kuanda, LU Zhiguo. Determination of cobalt,copper,iron,manganese,calcium, magnesium and aluminum in crude cobalt hydroxide by energy dispersive X-ray fluorescence spectrometry with powder pellet preparation. , 2024, 44(3): 30-35.
