柴油清净剂中氮含量对硫测定结果的影响及消除方法

针对紫外荧光法测定柴油清净剂中总硫含量时氮元素的干扰问题，研制了高氮抑制器用于消除氮含量对硫测定结果的影响，安装高氮抑制器后建立了工作曲线，考察工作曲线的线性及方法的精密度和检测下限。结果表明：安装高氮抑制器后，解决了紫外荧光法测定柴油清净剂中总硫含量时氮的严重干扰问题，提高了方法的准确度；工作曲线的线性可达0.999 8，实用检测下限可达0.2 mg/L，连续测定实际样品的相对标准偏差小于5%。

STUDY ON INFLUENCE OF NITROGEN CONTENT ON DETERMINATION OF TOTAL SULFUR IN DIESEL FUEL DETERGENTS AND ELIMINATION METHOD

Nitrogen element exerts strong interference in the ultraviolet fluorescence method for determination of total sulfur content in detergent additives for diesel fuel and results in great inaccuracy. This problem was investigated and solved by using high nitrogen suppressor. The effects of the installation of high nitrogen suppressor on elimination of the interference were studied. The working curve was established and the linearity of the working curve was investigated after the test condition was set up. The accuracy and the lower limit of detection of sulfur content were also investigated. The results showed that the strong interference problem is solved and the accuracy of the method is improved in determination of total sulfur content in diesel detergent additives. The working curve is linear up to 0.9998; the practical detection the lower limit is 0.2 mg?L-1. The relative standard deviation is less than 5% in the determination of practical samples.