气相色谱法测定蒸馏酒中甲醇含量

Determination of Methanol in Distilled Alcohol by Gas Chromatography

该试验旨在比较不同气相色谱柱及内标法和外标法检测甲醇含量的差异。通过2种色谱柱DB-WAX(60m×0.25 mm×0.25μm)、DB-1701(30 m×0.53 mm×1.0μm)及内标法和外标法在甲醇检测中的结果对比,结果发现DB-1701色谱柱峰形更好,更适合甲醇定量分析;外标法与内标法相比,操作简便、回收率更高,精密度、检出限、定量限无显著差异。在实验室仪器设备运行状态良好、实验室人员操作熟练情况下,外标法从实验的简便程度到准确度上均优于内标法。

There is a comparison of different gas chromatographic columns,internal standard method and external standard method for the determination of methanol content.Compared with the results of two chromatographic columns DB-wax(60 m×0.25 mm×0.25μm),DB-1701(30 m×0.53 mm×1.0μm),internal standard method and external standard method in methanol detection,the results show that DB-1701 chromatographic column has better peak shape and is more suitable for quantitative analysis of methanol.Compared with internal standard method,external standard method is easier to operate and has higher recovery rate.There is no significant difference in precision,detection limit and quantitative limit.The external standard method is superior to the internal standard method in terms of the simplicity and accuracy of the experiment when the laboratory equipment is in good operation and the operators are skilled.