A method to determine acrylic acid in workplace air was developed by on-line methylation gas chromatography. Methods: the samples were absorbed by solvent desorption silica gel tube and desorbed by methanol. Desorption fluid in the injector at 350 ℃ in the presence of an organic alkali tetramethylamine hydroxide (TMAH, 25% methanol) , allowed quantitative analysis of acrylic acid as its corresponding methyl derivative by gas chromatography. Results: calibration curve of the method was linear within the range 0-258.4 mg/L and showed good linearity with r=0.999 4. The determination limit of the method was 0.9 mg/L, and the minimum detection concentration was 0.06 mg/m(3) (collect 15 L air) . The relative standard deviation (RSD) was 2.2%-2.7% (n=5) . Recoveries were between 96.9-101.6%. Conclusion: the results prove on-line methylation gas chromatography is an accurate, simple and high sensitive method for determining acrylic acid in workplace air.
目的： 建立在线甲基化-气相色谱法测定工作场所空气中丙烯酸浓度的方法。 方法： 2018年1至7月用溶剂解吸型硅胶管采集空气中的丙烯酸，甲醇解吸后，解吸液与衍生化试剂四甲基氢氧化铵（TMAH，25%甲醇溶液）同时进样,在350 ℃的进样口生成丙烯酸甲基衍生物，经气相色谱测定。 结果： 在0~258.4 mg/L浓度范围线性关系良好，相关系数为0.999 4，方法的检出限为0.9 mg/L，最低检出浓度为0.06 mg/m(3)（以采集15 L空气计），5次平行测定相对标准偏差（RSD）在2.2%~2.7%，加标回收率在96.9~101.6%。 结论： 结果表明该法有效、简便、准确，可以用于工作场所空气中丙烯酸浓度的测定。.
Keywords: Acrylic acid; Air; Chromatography, gas; Methylation; Tetramethylamine hydroxide; Workplace.