气相色谱法同时测定工作场所中甲醇和苯系物

目的：探讨一次采样气相色谱同时测定工作场所中甲醇、苯、甲苯和二甲苯的方法。方法：用活性炭管采集、二硫化碳解吸、HP123-0732（DB-1701）型毛细管柱分离、氢火焰检测器检测、气相色谱法同时测定工作场所中甲醇、苯、甲苯和二甲苯,探索检测条件,并进行方法学研究。结果：该方法最低检测浓度：甲醇0.047 mg/m3,苯0.033 mg/m3,甲苯0.037 mg/m3,二甲苯0.041 mg/m3;相对标准偏差：甲醇在0.46%～1.89%之间,苯在0.855～4.74%之间,甲苯在1.35%～3.45%之间,二甲苯在1.87%～5.68%之间;平均采样效率为甲醇97.6%,苯94.4%,甲苯98.5%,二甲苯100.8%;平均解吸效率为甲醇98.8%,苯95.6%,甲苯97.5%,二甲苯99.8%。结论：该方法简单、适用,重现性好,灵敏度高,结果令人满意。

Determination of methanol,benzene,toluene and xylene in air of workplace by gaschromatography

Objective:To establish the method of detecting methanol,benzene,toluene and xylene with gas-chromatography in the air of workplace.Methods:Activated carbon as absorbent,HP123-0732(DB-1701),FID were selected,Gas-chromatography was used in this experiment.We probed the condition and study on the method in the experiment.Results:The lowest detecting concentration were 0.047 mg/m3 for methanol,0.033 mg/m3 for benzene,0.037 mg/m3 for toluene,0.041 mg/m3 for xylene,respectively.The relative standard deviations(RSD) were 0.46%~1.89% for methanol,0.85%~4.74% for benzene,1.35%~3.45% for toluene,1.87%~5.68% for toluene,respectively.The average trapping efficiencies were 97.6% for methanol,94.4% for benzene,98.5% for toluene,100.8% for xylene,respectively.The average de-absorption efficiencies were 98.8% for methanol,95.6% for benzene,97.5% for Toluene,99.8% for xylene,respectively.Conclusion:This method is simple,sensitive,proper and well repeatable.