顶空-气相色谱法测定土壤中甲醇的含量

GC Determination of Methanol in Soils with Headspace

摘要: 采用顶空-气相色谱法测定土壤中甲醇的含量。顶空平衡温度为80℃，顶空平衡时间为15 min。用DB-WAX石英毛细管色谱柱（30 m×0.53 mm，1.00 μm）分离，氢火焰离子化检测器检测。甲醇的质量分数在0.791~197 mg·kg^-1内与其对应的峰面积呈线性关系，检出限（3.14s）为0.37 mg·kg^-1。以空白样品为基体制得加标样品（39.5 mg·kg^-1），测定值的相对标准偏差（n=7）为2.7%。在7.91，79.1，158 mg·kg^-1等3个浓度水平进行加标回收试验，回收率为99.4%~103%。

Abstract: GC was applied to the determination of methanol in soils with headspace. The equilibrium temperature and time of headspace were set at 80℃ and 15 min. The analyte was separated on DB-WAX quartz capillary chromatographic column (30 m×0.53 mm, 1.00 μm) and detected by FID. Linear relationship between values of peak area and mass fraction of methanol was kept in the range of 0.791-197 mg·kg^-1, with detection limit (3.14s) of 0.37 mg·kg^-1. The spiked sample (39.5 mg·kg^-1) was prepared on the base of blank sample, giving value of RSD (n=7) of 2.7%. Tests for recovery were made by standard addition method at the concentration levels of 7.91, 79.1, 158 mg·kg^-1, giving values of recovery in the range of 99.4%-103%.