制革车间空气中羧酸类化合物的顶空气相色谱测定法

Determination of carboxylic acids in the air of leather workshop by Headspace Gas Chromatography

探讨用顶空气相色谱法同时测定工作场所空气中，甲酸、乙酸、丙酸和丙烯酸4种羧酸类化合物的适宜条件。流量为300mL／min采集空气试样4．5L，经硫酸溶液解吸后，在顶空平衡时间为60min，平衡温度为50％条件下用气相色谱FID检测器，以FFAP毛细管柱分离测定。甲酸、乙酸、丙酸和丙烯酸的加标回收率分别为95．3％、96．8％、105％和94．6％；方法最低检出浓度分别为0．4mg／m^3、7．7mg／m^3、3．4mg／m^2和6．6mg／m^3；相对标准偏差（RSD）为5．84％～8．98％。结果表明，该方法有较高的灵敏度和理想的准确度，并能达到规定的检出限，适用于制革车间空气中羧酸类化合物的测定。

in this paper, we explored the suitable conditions for the simultaneous determination of 4 kinds of carboxylie acids, such as formic acid, acetic acid, propionic acid and acrylic acid in the air of workplace by headspace gas chromatographic method. The optimized parameters are as follow： at air flow of 300 mL/min, 4.5 L of air was sampled and desorbed by sulfuric acid solution, and then was tested by gas chromatography with FID detector and FFAP capillary column after having been kept in the headspace for the equilibrium time of 60 min at the equilibrium temperature of 50℃. For formic acid, acetic acid, propionic acid and acrylic acid, spike recovery rate are 95.3% , 96. 8% , 105% and 94.6% respectively, the minimum detectable concentrations are 0. 4 mg/m3 , 7.7 mg/ m3, 3.4 mg/m3 and 6.6 mg/m3, and the relative standard deviations （ RSD% ） range from 5.84% to 8.98%. Results show that the method has high sensitivity and good accuracy, and can meet the requirement on relevant detection limits and therefore is suitable for determination of carboxylic acid compounds in air of leather workshop.