顶空-毛细管气相色谱法分析气体样品中的甲醇

Analyzing Methanol in Air Samples by Capillary Gas Chromatography Coupled with Headspace

采用顶空-毛细管气相色谱技术建立了测定气体样品中甲醇的方法，并利用正交设计法研究了顶空实验条件，优化了顶空炉箱温度和加热平衡时间。在最佳实验条件下，甲醇的方法检出限为0.04 mg/L，线性范围为0.16～7.92 mg/L。其加标回收率为94.5%～102.5%，相对标准偏差为1.39%～7.55%。当采样体积为20 L时，方法的最低检出限为0.01 mg/m3。该方法能够满足污染源及无组织排放的气体样品中甲醇的测定需求。

A method for determining methanol in gas sample by gas chromatography coupled with headspace was established. In experimental process, the effecting factors such as the temperature of oven and the time of heating balance were optimized with orthogonal design method. Under the optimum conditions, the limit of detection was 0.04 mg/L, the calibration graph was linear in the range of 0.16~7.92 mg/L. The recoveries of the method were 94.5%~102.5%, and the relative standard deviations ranged from 1.39% to 7.55%. When sampling volume was 20 L, the minimum detection limit was 0.01 mg/m3. Importantly, the approach could reach the requirement of determination of methanol in gas sample of urban pollution and fugitive emission.