八极杆碰撞/反应池-电感耦合等离子体质谱法测定渣油中的微量元素

Determination of Trace Elements in Residual Oil by Inductively Coupled Plasma Mass Spectroscopy With Octopole Reaction System

采用微波消解-八极杆碰撞/反应池(ORS)-电感耦合等离子体质谱法(ICP-MS)测定渣油中Na、Mg、Al、Ca、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Ga、As、Mo、Ag、Cd、Sn、Sb、Ba、Pb等22种微量元素的含量。样品用硝酸+双氧水分解后,直接用ICP-MS法同时测定上述微量元素;应用ORS技术,有效地消除了多原子离子对待测元素的干扰;选用Sc、Y、In、Bi等元素作内标混合液校正基体效应和信号漂移,确定了实验的最佳测定条件。结果表明,该方法对22种待测元素的检出限在0.001～0.076μg/L之间,相对标准偏差(RSD)均小于2.66%。该方法简便、快速、准确,可用于渣油的质量控制。

An analysis method of microwave digestion and inductively coupled plasma-mass spectroscopy （ICP-MS） with octopole reaction system（ORS） was established for the determination of 22 elements（Na, Mg, Al, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Mo, Ag, Cd, Sn, Sb, Ba and Pb） in residual oil. Samples were decomposed by HNO3 and H2O2 followed by dilution with ultrapure water, then analyzed directly by ICP-MS. The use of ORS can eliminate the interference of polyatomic ions dramatically. Sc, Y, In and Bi were used as internal standard elements to compensate matrix effect and signal drift. The optimum conditions for the determination were tested and discussed. Under the optimal conditions, the detection limits of the 22 elements were in the range of 0.001-0.076 ＆mu;g/L and the relative standard deviation（RSD） less than 2.66%. The method was simple, rapid and accurate, and can be applied for the quality control of residual oil.