气相色谱法测定工业纯苯中微量正庚烷含量

选用合适的色谱柱,重新建立气相色谱分析方法,准确测定工业纯苯中微量正庚烷含量,满足公司原料分析计划的检测要求。通过选择色谱柱型号,改变柱温、载气流速等参数,优化气相色谱条件,使杂质组分达到最佳分离。采用色谱柱为CP7773毛细管柱,氮气为载气,分流比为20∶1,运用程序升温模式,外标法测定正庚烷含量。得到线性回归方程为y=1.011x+0.666,相关系数r=0.999,标准偏差小于0.4(n=8),平均回收率为99.80%~101.20%。

Determination of the Concentration of Heptane in Industrial Benzene by Gas Chromatography

In order to meet the company＇s testing requirements tbr analysis of raw materials, I chose the appropriate column to re-establish gas chromatographic analysis methods and determine the accurate content of n-heptane in trace industrial benzene. By selecting the column model, changing the column temperature, carrier gas flow rate and other parameters to optimize the gas chromatography conditions, to achieve optimum separation of the impurity component. 1 used CP7773 capillary column with nitrogen as a carrier gas. The split ratio was 20 ： 1. By using temperature-programmed mode, n-heptane content was measured by external standard method. I obtained the linear regression equation y = 1.01 1x ＋0.666. The correlation coefficient r = 0.999. The standard deviation is less than 0.4 （n = 8）. The average recovery was 99.80 %- 101.20 %.