溶剂解吸-气相色谱法测定工作场所空气中甲基戊烷

Determination of methyl pentane in workplace air by solvent desorption-gas chromatography

目的建立溶剂解吸-气相色谱法测定工作场所空气中甲基戊烷。方法工作场所空气中甲基戊烷用活性炭管采集,以二硫化碳解吸后,经DB-1毛细管色谱柱分离,火焰离子化检测器检测,标准曲线法定量。结果 2-甲基戊烷和3-甲基戊烷的线性范围均为1.98~6 600.00 mg/L,相关系数均为0.999 9;最低检出限和最低定量限分别为0.06、0.20 mg/L;最低检出浓度和最低定量浓度分别为0.04、0.14 mg/m^(3)(以采集1.50 L空气计算);方法平均解吸效率为97.3%~102.2%;批内精密度(RSD)为0.4%~0.9%,批间RSD为0.3%~3.0%;采样效率为96.7%~100.0%,穿透容量为8.68 mg。样品在室温下至少可保存14 d。结论本方法适用于工作场所空气中甲基戊烷的测定。

Objective To establish a solvent desorption-gas chromatography method for determination of methyl pentane in workplace air. Methods Methyl pentane in workplace air was collected with activated carbon tube and desorbed with carbon disulfide, then separated by DB-1 capillary column, detected by flame ionization detector, and quantified by standard curve method. Results Good linearity was obtained in the range of 1.98-6 600.00 mg/L with the correlation coefficient of 0.999 9. The minimum detection limit and the minimum quantification limit were 0.06 and 0.20 mg/L, respectively. The minimum detection concentration and minimum quantification concentration was 0.04 and 0.14 mg/m^(3), respectively(calculated by collecting 1.5 L of air sample). The average desorption efficiency was 97.3%-102.2%. The within-run relative standard deviation(RSD) and the between-run RSD were 0.4%-0.9% and 0.3%-3.0%, respectively. The sampling efficiency was 96.7%-100.0% and the penetration capacity was 8.68 mg. The samples can be stored at room temperature for at least 14 days. Conclusion This method is suitable for methyl pentane detection in workplace air.