增压-微波消解电感耦合等离子体质谱法测定含难溶矿物岩石样品中的微量元素

摘要

研究建立了增压-微波消解电感耦合等离子体质谱法测定含难溶矿物(含铌钽铀矿物、锆石等)岩石样品中微量元素的测试方法.该技术有效地解决了传统湿法消解方法不能完全消解含难溶矿物(含铌钽铀矿物、锆石等)岩石样品的难题.根据超高压-微波消解原理,自行设计加工了电加热增压消解装置一台.该装置的技术创新在于对含难溶矿物岩石样品采用了在同一消解罐中先微波消解再增压消解的方式,解决了微波消解到增压消解的转换问题,实现了对含难溶矿物岩石样品的无交叉污染、低本底、快速地增压-微波消解.通过一系列研究获得了含难溶矿物(含铌钽铀矿物、锆石等)岩石样品的微波-增压消解条件参数,然后采用电感耦合等离子体质谱(ICP-MS)法测定含难溶矿物岩石样品中微量元素含量.经标准物质测试验证,分析方法的定量限为0.004~ 0.084 μg/g,精密度小于5%,测量相对误差小于10%,该方法能满足行业分析测试质量的控制要求.%A pressurize-microwave inductively coupled plasma mass spectrometry was established in this study with the purpose of determining trace elements in rock samples containing refractory minerals (niobium and tantalum bearing uranium minerals, zircon). The problem for traditional wet digestion method which cannot dissolve rock samples containing refractory minerals (niobium and tantalum bearing uranium minerals, zircon) completely was solved effectively by this technology. An electrical heating pressurized -microwave device was designed according to the principle of ultra-high pressure simulation - microwave digestion. The technical innovation of the device is that the rock samples containing refractory minerals were digested by microwave-digestion device and solved the problem of switching the sample from the microwave digestion device to pressurized digestion device by pressurized-digestion device in the same digestion jar, which achieve a rapid pressurized-microwave digestion method for rock samples containing refractory minerals without cross contamination and with low cost. The Pressurize-microwave digestion parameters for rock samples containing refractory minerals (niobium and tantalum bearing uranium minerals, zircon) were obtained by this paper and the inductively coupled plasma mass spectrometry (ICP-MS) was used to determine trace elements for rock samples containing refractory minerals, which satisfy the requirement of fast and accurate testing for uranium geological exploration. The method has been verified by certified reference materials analysis and the quantitative limits is of 0.004 — 0.084 μg/g, precision is of less than 5%, measuring relative error is less than 10%, which satisfy the requirement of quality control for analytical testing business.