Development of a Portable Li-K Analyzer and Its Application in the Determination of Lithium in Spodumene

• Published in: Yankuàng cèshì Vol. 35; no. 4; pp. 366 - 372
• Main Authors: Jiao, Ju, Yang, Xiao-tao, Yuan, Ji-hai, Fan, Xing-tao, Liu, Xiao, Zhan, Xiu-chun
• Format: Journal Article
• Language: Chinese; English
• Published: Science Press, PR China 01.07.2016
• Subjects: Analyzers; Atmospherics; charge coupled device (ccd); Charge coupled devices; Emission analysis; Lithium; Mathematical analysis; portable li-k analyzer; Rock; solution cathode atmospheric glow discharge; Spodumene; standard addition method
• ISSN: 0254-5357
• DOI: 10.15898/j.cnki.11-2131/td.2016.04.005

Most of the mineral resources of lithium and potassium are distributed in remote western China.Fast, on-site analytical techniques are urgently needed for their exploration and comprehensive utilization.In this work,a newly developed portable Li-K analyzer was introduced for its analytical performance and the application of this equipment in determining lithium in spodumene is also discussed.The analyser is a type of atomic emission spectrometer based on solution cathode atmospheric glow discharge. Sample solution was used as a graphite cathode,which atomized and excited the elements Li and K.A charge coupled device (CCD)was used to detect the characteristic lines of Li and K,which had wavelengths ranging from 345 to 1015 nm with a 3 nm resolution. Using a Li analytical line of 670.78 nm and a K analytical line of 769.90 nm under the optimized working conditions,the measurement precisions for Li and K were greater than 2%RSD with the limit of detection of 0.03 mu g/mL.Results show that different types and concentrations of acids strongly affect the intensities of Li and K,and co-existent elements produce serious matrix effect.Quantification of Li in spodumene ores by use of a calibration curve without matched matrix could not produce accurate results with relative standard deviation up to 267%. Standard addition methods can eliminate the influence of the matrix effect and obtain analytical results consistent with those by Inductively Coupled Plasma-Optical Emission Spectrometry,which thus provides a basis for on-site determination of Li in solid samples.