串联四极杆电感耦合等离子体质谱测定石脑油中痕量硫

Rapid Determination of Trace Sulfur in Naphtha by Tandem Quadrupole Inductively Coupled Plasma Mass Spectrometry

基于串联四极杆电感耦合等离子质谱(ICP-MS)建立了测定石脑油中痕量硫(S)的分析方法。石脑油经有机溶剂简单稀释后直接采用串联四极杆ICP-MS进行测定。在MS/MS模式下,选择N_(2)O作为反应气,基于S^(+)与N_(2)O分别发生O原子转移反应和N原子转移反应消除质谱干扰,优化了利用质量转移反应消除干扰的分析条件。通过与传统的O_(2)反应模式进行对比分析显示了该方法具有良好的分析性能,采用标准参考物质验证了该方法的准确性和可靠性。结果表明:在N_(2)O流速为0.25 mL/min条件下,S质量分数的检出限(LOD)分别为19.6 ng/kg(^(32)S)和23.5 ng/kg(^(34)S);相对标准偏差(RSD)小于4.5%;回收率为96.3%~104.0%。所建立的分析方法,样品处理简单,分析灵敏度高,准确性和精密度好,适用于石脑油中痕量S的快速测定。

An analytical method for the determination of trace sulphur(S)in naphtha was developed based on tandem quadrupole inductively coupled plasma mass spectrometry(ICP-MS).Naphtha was directly determined by tandem quadrupole ICP-MS after simple dilution with organic solvents.In MS/MS mode,N_(2)O was selected as the reaction gas,and the spectral interference was eliminated based on the O-atom transfer reaction and N-atom transfer reaction of S^(+)and N_(2)O,respectively.The analytical conditions for eliminating interference by mass-shiftr reaction were optimized.Compared with the traditional O_(2) reaction mode,the method shows good analytical performance,and the accuracy and reliability of the method have been verified using standard reference materials.The results show that the limit of detection(LOD)of ^(32) S and ^(34) S is 19.6 ng/kg and 23.5 ng/kg at N_(2)O flow rate of 0.25 mL/min,respectively.The relative standard deviation(RSD)is less than 4.5%,and the recovery is in the range of 96.3%—104.0%.The developed analytical method has simple sample processing,high analytical sensitivity,good accuracy and precision,and thus is suitable for the rapid determination of trace S in naphtha.