车用汽油样品用异辛烷溶剂适当比例稀释，直接进入电感耦合等离子体光谱仪（ICP-OES）测定硅元素。考察了稀释溶剂及稀释比例、标准物质类型、样品冷却温度、汽油样品组成等因素对硅含量测定的影响。结果表明，汽油样品用异辛烷按1∶1的比例混溶，在雾化室冷却温度为－10℃时，直接进入 ICP-OES测定硅含量效果最佳。在优化的工作条件下，该方法在0．1～10．0 mg·kg－1硅含量范围内线性良好，线性相关系数达0．99996，检出限为0．012 mg·kg－1，回收率在95．8％～98．4％之间，相对标准偏差小于3．0％。该法简便、快速、准确度高，适用于车用无铅汽油、车用乙醇汽油和低比例甲醇汽油中微量硅的快速检测。%A simple and accurate method was developed for determining silicon in gasoline using inductively coupled plasma optical emission spectroscopy (ICP-OES).For sample inroduction a Burgener nubulizer and a Cyclonic spray chamber were used.A gasoline sample was diluted with isooctane and then introduced into the cooled spray chamber of the ICP-OES.Good linearity was achieved in the silicon concentration range 0.1 ~10.0 mg·kg-1 ,and the correlation coefficient was 0.999 96.The detection limit for silicon was 0.012 mg· kg-1 and the silicon recoveries from gasoline samples were 95.8%~98.4%,with relative standard deviations of less than 3.0%.The method was proved to be simple,reliable and highly sensitive,and suitable for deter-mining silicon in samples of motor gasoline,ethanol-gasoline and methanol-gasoline fuel mixtures those contai-ning not more than 15% (V/V )oxygenates.
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