气相色谱测定空气中抽余油方法研究

Gas Chromatographic Determination of Raffinatc in Air by Charcoal Tube Collection and Thermal Desorption

建立了用活性炭管采集,热解吸,气相色谱测定车间空气中抽余油浓度的方法。方法检出限为5.3×10^(-1)g/L;变异系数为3.6％～6. 9％,合并变异系数为5.6％;三种浓度水平的解吸效率平均为98.7％,变异系数为4.2％。采用内装100mg活性炭的采样管,在500mg/m^3正己烷、空气湿度57％～92％时,以0.3L/min的速度采样,穿透容量为14.2mg。采已知量的抽余油活性炭管,在室温下放置10天,结果无显著差异。

Raffinate in workplace air was collected by charcoal tube and desorbed by thermal and then determined by GC. This method was found to have a limit of de-rection of 5- 3 × 10-1 g/ L and a coefficient variation of 5.6%. This method is to draw a Known volume of air through an absorption tube packed with activated charcoal (20 - 10 mesh) with the help of a 100ml glass syringe. The absorption tube is made of glass of 7cm × 1-0mm i. d. The samples collected on charcoal were then desorbed by heating the tube to 300 C and flushed with nitrogen at a flow rate of 50 ~ 60ml/min to remove the absorbed compounds. After sampled charcoal tubes containing Known amounts of Raffinate were stored at room temperature for 10 days no significant different results were showed.