Simultaneous Determination of Diethylamine, Triethylamine and Ethyldiamine in Air of Workplace by Ion Chromatography

A method for the simultaneous determination of diethylamine, triethylamine and ethyldiamine in air of workplace by ion chromatography was proposed. The workplace air sample was collected by alkaline silicone tube, and desorbed with 10.0 mL of 0.01 mol·L^-1 sulfuric acid solution by ultrasonic for 20 min. After filtration through a 0.22 μm water phase needle filter, the filtrate was injected into an ion chromatograph. The IonPac CS17 cationic analysis column was used as the stationary phase, and 10 mmol·L^-1 methanesulfonic acid solution was used as the rinsing solvent to separate the 3 targets, with determination by conductivity detector and quantitation by external standard method. As shown by the results, linear relationships between mass concentrations of diethylamine, triethylamine and ethyldiamine and corresponding peak areas were kept in the ranges of 19.1-114.4 mg·L^-1, 15.8-94.6 mg·L^-1 and 2.7-16.3 mg·L^-1, with detection limits (3s) of 0.012, 0.018, 0.017 mg·L^-1, respectively. Test for recovery was made on the blank alkaline silicone tubes according to the standard addition method, giving results in the range of 88.4%-102%, with RSDs (n=6) of the determined values less than 4.0%. The method was used to analyze 5 air samples from a chemical enterprise, in which diethylamine and triethylamine were not detected, and the mass concentration of ethyldiamine was in the range of 0.47-1.78 mg·m^-3.