工作场所空气中正戊烷、正庚烷和正辛烷的气相色谱同时测定法

目的建立工作场所空气中正戊烷、正庚烷、正辛烷的溶剂解吸气相色谱测定方法。方法采用活性炭管采集,二硫化碳解吸,经DB-1毛细管色谱柱分离的气相色谱测定方法。结果该方法正戊烷、正庚烷、正辛烷线性范围分别为0.3～3131、0.3～3418和0.3～7025mg/L,线性方程分别为：Y=1.910X＋23.00（r=0.99991）、Y=2.251X-10.64（r=0.99998）和Y=2.305X-34.45（r=0.99997）;检出限均达到0.3mg/L;方法的重现性好,相对标准偏差分别为0.2%～0.6%、0.4%～0.8%和0.4%～0.8%;平均解吸效率分别为98.0%～105.2%、99.1%～101.4%和98.7%～99.3%。结论该方法检出限低,精密度和准确度高,可完全适用于工作场所空气中正戊烷、正庚烷、正辛烷的测定。

Simultaneous Determination of N-pentane, N-heptane and N-octane in The Air of Workplace by Gas Chromatography

[Objective]To establish solvent desorption gas chromatographic method for determination of n-pentane、n-heptane and noctane in the air of the workplace.[Methods]Capillary gas chromatography was applied to collect samples with activated carbon tube and separate with DB-1 capillary columns.[Results]Linear limits of the methods was 0. 3 ～ 3131 mg/L for n-pentane,0. 3 ～ 3418 mg/L for n-heptane,and 0. 3 ～ 7025 mg/L for n-octane. The linear equation were Y = 1. 910X ＋ 23. 00（ r = 0. 999 91） ,Y = 2. 251X-10. 64（ r = 0. 999 98） and Y = 2. 305X-34. 45（ r = 0. 999 97） respectively. The limits of detection were 0. 3 mg/L . The determination has a good reproducibility . Their relative standard deviations （ RSD） were 0. 2% ～ 0. 6% ,0. 4% ～ 0. 8% and 0. 4% ～ 0. 8% respectively. The average desorption efficiencies were 98. 0% ～ 105. 2% ,99. 1% ～ 101. 4% and 98. 7% ～ 99. 3% .[Conclusion] The method shows lower detection limit,high accuracy and precision. It is feasible for determination of n-pentane、n-heptane and noctane in workplace air.