双柱切换-反吹技术在醇类汽油苯类分析中的应用

利用双柱切换和反吹技术,将预柱中的待测组分切换到分析柱中,建立醇类汽油中苯和甲苯含量的检测方法。在进样状态下,被测组分先进入非极性的预切柱(10%OV-101)进行分离,当被测组分苯和甲苯从预柱中流出后,切换六通阀到反吹状态,放空重组分,使苯和甲苯进入强极性的微填充TCEP不锈钢柱进行分析检测。通过实验考察了阀切换时间对测定结果的影响,同时对方法的准确度和精密度进行验证。结果表明:苯和甲苯的检测范围为0.10%~5.00%和0.50%~15.00%,加标回收率为97.5%~105.0%,该方法的相对标准偏差小于1.09%。该方法操作简单,检测结果准确、可靠。

Application of double column switch-backblowing technique in benzene analysis of alcohol gasoline

A test method for the content of benzene and toluene in alcohol-based gasoline was established by switching components from the precolumn to the analytical column using double column switching and backblowing techniques.In the injection state,the tested components were separated by entering the non-polar pre-cut column(10%OV-101).When benzene and toluene were discharged from the pre-column,the six-way valve was switched to the backblowing state,and the benzene and toluene were discharged into the micro-filled TCEP stainless steel column with strong polarity for analysis and detection.The effect of valve switching time on the measurement results was investigated by experiments,and the accuracy and precision of the method were verified.The results showed that the detection range of benzene and toluene was 0.10%~5.00%and 0.50%~15.00%,and the spiked recoveries were 97.5%~105.0%.The relative standard deviation of this method was less than 1.09%.The method was simple to operate and the test results were accurate and reliable.