Laser-Induced Breakdown Spectroscopy (LIBS) Measurement of Uranium in Molten Salt
Laser-Induced Breakdown Spectroscopy (LIBS) Measurement of Uranium in Molten Salt
复制标题
熔盐中铀的激光诱导击穿光谱 (LIBS) 测量
作者：
Ammon N. Williams;S. Phongikaroon
在目前的研究中，熔盐气溶胶激光诱导击穿光谱（LIBS）系统被用来测量铀（U）的含量在三元UCl 3-LiCl-KCl盐调查和评估近实时分析方法的材料保障和问责制。使用五种不同的U浓度进行实验，以确定系统相对于U的分析品质因数。在分析中，使用三条U线在367.01 nm、385.96 nm和387.10 nm线处绘制单变量校准曲线。367.01 nm谱线的最低检测限（LOD）为0.065重量% U。385.96 nm线具有0.20 wt% U的最佳交叉验证均方根误差（RMSECV）。除了单变量校准方法外，还开发了多变量偏最小二乘（PLS）模型以进一步分析数据。使用偏最小二乘（PLS）建模，确定RMSECV为0.085重量% U。从多变量方法的RMSECV是显着优于单变量的情况下，PLS模型建议用于未来的LIBS分析。总体而言，气溶胶LIBS系统在监测U浓度方面表现良好，并且预计该系统可用于定量确定高温处理熔盐中U的正常操作浓度内的U成分。
In this current study, the molten salt aerosol–laser-induced breakdown spectroscopy (LIBS) system was used to measure the uranium (U) content in a ternary UCl3–LiCl–KCl salt to investigate and assess a near real-time analytical approach for material safeguards and accountability. Experiments were conducted using five different U concentrations to determine the analytical figures of merit for the system with respect to U. In the analysis, three U lines were used to develop univariate calibration curves at the 367.01 nm, 385.96 nm, and 387.10 nm lines. The 367.01 nm line had the lowest limit of detection (LOD) of 0.065 wt% U. The 385.96 nm line had the best root mean square error of cross-validation (RMSECV) of 0.20 wt% U. In addition to the univariate calibration approach, a multivariate partial least squares (PLS) model was developed to further analyze the data. Using partial least squares (PLS) modeling, an RMSECV of 0.085 wt% U was determined. The RMSECV from the multivariate approach was significantly better than the univariate case and the PLS model is recommended for future LIBS analysis. Overall, the aerosol-LIBS system performed well in monitoring the U concentration and it is expected that the system could be used to quantitatively determine the U compositions within the normal operational concentrations of U in pyroprocessing molten salts.