有机溶剂辅助微波消解-电感耦合等离子体质谱法测定多种原油中微量金属元素

Determination of Trace Metal Elements in Crude Oils by Microwave Digestion-Inductively Coupled Plasma-Mass Spectrometry Assisted with Organic Solvent

摘要: 建立了二氯甲烷溶剂辅助微波消解-电感耦合等离子体质谱法测定原油中V、Cr、Fe、Ni、Cu、Zn、Mo、Co、Pb等16种微量金属元素。研究表明,用CH₂Cl₂分散原油样品,以浓HNO₃-H₂O₂为消解体系,采用CEM微波消解系统消解样品,各元素线性关系良好,相关系数≥0.9995;检出限可达ng/L;方法精密度较高,相对标准偏差(RSD,n＝3)<5.0%;回收率为92%~110%。以w(Ni)/w(V)与w(Fe)/w(V)比值为变量参数对不同原油样品进行聚类分析,表明国内与国外不同地区原油样品中各金属元素含量差异较大。

Abstract: A method for determination of V, Cr, Fe, Ni, Cu, Zn, Mo Co, Pb, etc in different crude oils was established by inductively coupled plasma-mass spectrometry assisted with organic solvent microwave digestion. The oil sample was digested by microwave using HNO₃-H₂O₂ as oxidant after dispersing in organic solvent (CH₂Cl₂). The results showed that the detection limits of the method reached ng/L level for sixteen elements. The linear correlation of the method was preferable with the correlation coefficient of better than 0.9995. The recoveries of the method were in the range of 92%~110% with the precision of less than 5.0%RSD (n＝3). The ratios of w(Ni)/w(V) and w(Fe)/w(V) were distinct in different crude oil samples from oversea and domestic, and the index can be used to the cluster analysis for differencing the crude oil samples.