激光剥蚀电感耦合等离子体质谱测定岩石样品中稀土元素

以NIST612玻璃标准为外标校正物质, 采用42Ca为内标校正灵敏度漂移、基体效应、剥蚀效率及进样量的变化.将LSX-2 0 0激光剥蚀进样系统与POEMSIII电感耦合等离子体质谱仪联用, 对国际标准物质BCR-2 (玄武岩) 及国内标准物质GSR-11 (花岗岩) 玻璃熔饼进行了稀土元素的测定, 建立了LA -ICP -MS整体分析岩石样品中稀土元素的方法.结果表明, 绝大多数稀土元素准确度优于15 %, 测定精度(RSD) 小于10 %.稀土元素的检出限(LOD) 在21.4×10-9~23 1.6×10-9之间, 样品分析速度为2 0样品/h.在Excel软件下用VBA语言编制宏, 实现了脱机数据处理的自动化, 极大提高了工作效率. 

RARE EARTH ELEMENTS ANALYSIS OF GEOLOGICAL SAMPLES BY LA-ICP-MS

This paper describes recent work in applying a laser ablation system (LSX-200) hyphenated with POEMSIII inductively coupled plasma mass spectrometry (LA-ICP-MS) for the in situ analysis of solid geological materials. It demonstrates the potential of LA-ICP-MS for the determination of geochemically important trace and ulra-trace elements (REE for instance) following XRF routine sample preparation. NIST SRM 612 was employed as external calibration standard and Ca as internal standard to correct for signal drift, difference in transport efficiency and sampling yield.Resultsagree well with the certified value with accuracy better than 15%, RSD less than 15% for most determined rare earth elements. LOD from 21.4×10-9 to 231.6×10-9 and less than 100×10-9 for majority trace elements determined. In addition, Home-made macro function by VBA language under Excel software greatly enhanced off-line data reduction efficiency.