顶空-气相色谱法与吹扫捕集-气质联用法测定水中乙醛、丙烯醛、丙烯腈、吡啶的方法比较

为了进一步提高实验室测定水中乙醛、丙烯醛、丙烯腈、吡啶含量的效率和准确度,对顶空-气相色谱法与吹扫捕集-气质联用法测定水中乙醛、丙烯醛、丙烯腈、吡啶的检出限、精密度、回收率等进行了比较。顶空-气相色谱法的精密度范围在1.4%~3.8%之间,回收率范围在93.2%~101.0%之间。吹扫捕集-气质联用法的精密度范围在1.7%~3.2%之间,回收率范围在92.3%~99.8%之间。2种方法的线性良好,吹扫捕集-气质联用法具有较低的检出限。结果表明,这2种方法均能准确地定量水中乙醛、丙烯醛、丙烯腈、吡啶的含量;吹扫捕集-气质联用法的灵敏性更高,适用于低浓度样品的监测;顶空-气相色谱法适用于高浓度或较脏样品的监测。

Comparison of headspace-GC with purge and trap-GC/MS methods in determination of acetaldehyde, acrolein,

In order to further improve the efficiency and accuracy of determination of acetaldehyde, acrolein, acrylonitrile, pyridine in water. The detection limit, precision and recovery of acetaldehyde, acrolein, acrylonitrile and pyridine in water by gas chromatography with purge and trap GC/MS methods are compared. The precision of headspace-gas chromatography is between 1.4%~3.8%, and the recovery rate is between 93.2%~101.0%. The precision of purge and trap-GC/MS is between 1.7%~3.2%, and the recovery rate is between 92.3%~99.8%. The linearity of the two methods is good, and the purge & trap-GC/MS method has a lower detection limit. The result shows that the two methods can accurately determine acetaldehyde, acrolein, acrylonitrile and pyridine in water. The sensitivity of purge and trap-GC/MS method is higher, suitable for the determination of low concentration samples; the headspace-gas chromatography is suitable for the monitoring of high concentration or dirty samples.