LA-ICP-M S结合超高压粉末压片技术快速分析碳酸盐岩中Mg,Ca,Sr,Ba和轻稀土元素

Rapid determination of Mg,Ca,Sr,Ba and LREEs in carbonate by laser ablation-inductively coupled plasma-mass spectrometry in combination with high pressure tableting technique

建立了激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)结合超高压粉末压片技术定量分析碳酸盐岩中的Mg,Ca,Sr,Ba和LREEs方法。对于碳酸盐岩粉末,超高压(2000 kN)粉末压片的激光剥蚀行为可控,而常规压力(200 kN)粉末压片的剥蚀行为不可控。在选定的激光剥蚀条件下,NIST SRM 610和MACS-3之间没有明显的基体效应,但NIST SRM 610和GBW07127~07136超高压粉末压片之间有较明显的基体效应(Ba和LREEs)。当激光束斑直径在90~130μm时,LA-ICP-M S的分析精度在20%以内。采用了'基体效应指数'校正了相对于NIST SRM 610的基体效应,'基体效应指数'由GBW07129和GBW07130的分析结果计算得出。将本方法应用于GBW07127~07136系列标准物质中,所得的大多数分析结果(Mg,Ca,Sr,Ba和LREEs)的准确度在20%以内。

A protocol for rapid determination of Mg,Ca,Sr,Ba and LREEs elements in carbonate by laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)in combination with high pressure tableting technique was presented.The results revealed that the laser ablation behavior of carbonate powder pellets tableted at high pressure(2000 kN)was well controlled,while the less controlled behavior was observed at conventional pressure(200 kN).No matrix effect existed between NIST SRM 610 and MACS-3 under the laser conditions used in this study,while distinguishable matrix effects for Ba and LREEs between NIST SRM 610 and GBW07127-07136 powder pellets existed.The precision was within 20%when the laser spot size was in the range of 90-130μm.The'matrix effect factor',which was derived as the average of GBW07129 and GBW07130,was used to correct the NIST SRM 610 normalized data for other carbonate powder pellets.The proposed technique was used to analyze Mg,Ca,Sr,Ba and LREEs in ten carbonate reference materials,and the accuracy was better than 20%for the most elements.