自动快速燃烧-离子色谱联用技术测定轻质油中痕量氯

Determination of trace chlorine in light oil by automatic rapid combustion-ion chromatography combined technology

采用自动快速燃烧-离子色谱联用技术,以质量浓度0.5 mg/L轻质油含氯标准溶液为研究对象,确定了用于测定轻质油中痕量氯的最佳分析条件:燃烧管进(出)口温度为950(1000)℃,样品进样量为50μL,吸收液超纯水用量为10 mL。结果表明:当含氯质量浓度为0.1~1.0,1.0~10.0 mg/L时,所建立的标准曲线线性相关系数分别为0.9991,0.9997;在最佳分析条件下,连续测定92~#汽油、0~#柴油、轻质燃料油、苯和甲醇各5次,加标样品中含氯量测定结果的相对标准偏差为1.25%~3.95%,加标回收率为91.58%~95.42%,方法的重复性良好,分析结果准确可靠。

The following optimum analytical condi-tions for the determination trace chlorine in light oil were established by using automatic rapid combus-tion-ion chromatography combined technology with the mass concentration of 0.5 mg/L light oil contai-ning chloride standard solution as the research ob-ject:the inlet(outlet)temperature of the combustion tube of 950(1000)℃,the sample injection quantity of 50μL and the ultrapure water(10 mL)as absorp-tion solution.The results showed that when the chlo-rine mass concentration was 0.1-1.0,1.0-10.0 mg/L,the linear correlation coefficients of the standard curve were 0.9991,0.9997.Under the best analytical conditions,the chlorine content of the 92#gasoline,0#diesel,light fuel oil,benzene and methanol were measured consecutively for 5 times,the relative standard deviations of the measurement results of chlorine content in the labeled samples were 1.25%-3.95%and their standard recovery rates were 91.58%-95.42%.The method had good repeatability and the analysis results were ac-curate and reliable.