顶空气相色谱法测定水中的乙醛和丙醛

Determination of Acetaldehyde and Propionaldehyde in Water by Headspace Gas Chromatography

摘要: 乙醛和丙醛是工业上常用的重要化工原料，广泛应用于合成药物、塑料、染料、纤维等方面。在我国地表水、地下水和工业废水中常能检出乙醛和丙醛等醛类化合物。顶空是用于气相色谱样品制备最重要的技术之一。采用顶空毛细管气相色谱法，建立了水中乙醛和丙醛的分析方法。实验结果表明：适宜的顶空平衡温度为30℃，平衡时间为20 min。该方法操作简单，线性关系好(R² > 0.99)，准确度好，精密度高。乙醛和丙醛的平均回收率分别为95.63%~106.11%和87.33%~110.10%。相对标准偏差分别为1.28%~5.52%和1.94%~5.49%。

Abstract: Acetaldehyde and propionaldehyde are important chemical raw materials commonly used in industry, and are widely used in the fields of synthetic drugs, plastics, dyes, fibers, etc. Aldehydes such as acetaldehyde and propionaldehyde can often be detected in surface water, underground water, and industrial wastewater in China. Headspace is one of the most important techniques for gas chromatography sample preparation. A simple and fast method based on headspace capillary gas chromatography is proposed for acetaldehyde and propionaldehyde in water. The results show that the optimum headspace equilibrium temperature is 30˚C and the equilibrium time is 20 min. The method is simple to operate with good linearity in the considered concentration ranges (R² > 0.99). Average recoveries of acetaldehyde and propionaldehyde for spiked standards (n = 7) are 95.63% - 106.11% and 87.33% - 110.10%. Average relative standard deviations (RSD) of acetaldehyde and propionaldehyde are 1.28% - 5.52% and 1.94% - 5.49%, which showed good accuracy and high precision for the proposed analytical method.