ICP-MS法测定钼矿石中伴生锂、镓和稀土元素

通过比较氢氟酸-硝酸高压罐密闭消解法、 氢氟酸-硝酸-高氯酸-盐酸低压密闭消解法和氢氟酸-硝酸-高氯酸-盐酸敞口消解法对钼矿样品的分解效果， 选用低压密闭消解法制备样品， 用电感耦合等离子体质谱（ICP-MS)法测定伴生稀有元素Li，Ga和15种稀土元素的质量比. 通过对干扰元素的分析， 选择合适同位素， 并确定¹⁵¹Eu，¹⁵⁷Gd，¹⁵⁹Tb质谱干扰的校正系数. 结果表明，  20 μg/L的铑（Rh）标准溶液作为内标可有效抑制溶液中的基体效应和信号动态漂移， 方法检出限为0.001~0.113 μg/g， 相对标准偏差（RSD， n=7）为0.30%~3.92%.  经标准物质和实际样品验证， 该方法可靠， 适合钼矿中伴生Li，Ga和稀土元素的测定.

Determination of Associated Lithium,Gallium and Rare Earth Elements in Molybdenum Ore by Inductively Coupled Plasma Mass Spectrometry Method

By comparing the digestion effects of hydrofluoric acid-nitric acid high pressure tank closed digestion method, hydrofluoric acid-nitric acid-perchloric acid-hydrochloric acid low pressure closed digestion method and hydrofluoric acid-nitric acid-perchloric acid-hydrochloric acid open digestion method on molybdenum ore samples, the low pressure closed digestion method was selected to prepare samples, the inductively coupled plasma mass spectrometry  (ICP-MS) method was used to determine the mass ratio of associated rare elements lithium，  gallium and other 15  rare earth elements in molybdenum ore. Through the analysis of interfering elements, the suitable isotope was selected and the correction coefficients of ¹⁵¹Eu，¹⁵⁷Gd，¹⁵⁹Tb mass spectrum interference was determined. The results show that the standard solution of 20 μg/L rhodium is used as an internal standard solution can effectively inhibit matrix effect and signal dynamic drift in the solution,  the detection limit of the method is  0.001—0.113 μg/g，  and the relative standard deviation （RSD, n=7） is  0.30%—3.92%，  which is verified by standard materials and actual samples. The method is reliable and suitable for the determination of associated lithium，  gallium and rare earth elements in molybdenum ore.