ICP-MS法测定高纯石墨中的痕量杂质元素

Determination of Impurity Elements in High Purity Graphite by Inductively Coupled Plasma-Mass Spectrometry

高纯石墨于马弗炉中900℃下至完全灰化,碱熔融分解灰分,盐酸溶解熔块,电感耦合等离子体质谱测定高纯石墨灰分中L i、Be、Ti、V、Cr、Mn、N i、Co、Cu、Ga、Sr、Y、Zr、In、Sb、Ba、La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、B i等31种杂质元素。考察了熔解灰分的助熔剂中各成分的比例,优化了仪器工作条件,选择同位素克服质谱干扰,比较了4种内标元素的校正效果。杂质元素的检出限在0.000 8-0.1 ng/mL,加标回收率达到93%~105%,相对标准偏差（RSD,n=10）为0.57%-6.5%,该法适用于高纯石墨中痕量杂质元素的测定。

High purity graphite was burned in the Muffle furnace under 900 ℃. Alkali fusion dissolved the ash. ICP - MS was utilized to determine the impurity elements including Li, Be, Ti, V, Cr, Mn, Ni Co, C u, Ga, Sr, Y, Zr, In, Sb, Ba, La, C e, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Bi. Different proportions of each component in flux were studied. We optimized the working conditions of the instrument, selected the isotope mass spectrometry to overcome interference. The effects of different internal standard elements on the results were investigated. The detection limits of impurity elements were from 0. 000 8 ng/mL to 0. 1 ng/mL. The recovery rates were between 93% and 105%. The RSD （n = 10） were in the range of 0.57% and 6.5%. This method is suitable for the determination of impurity elements in the high purity graphite.