Static headspace analysis of aliphatic amines in aqueous samples

Static headspace preconcentration was developed for the gas chromatographic analysis of aliphatic amines in aqueous samples. A liquid-gas ratio of 1, an incubation temperature of 80 degrees C (15 min), a pH of 13.7 and a mixt ure of salts (NaCl and K2SO4) at saturation concentration gave a maximal he adspace amine concentration. C-1-C-4 volatile aliphatic amines were separat ed on a specific PoraPLOT Amines capillary column. The detection limit was 0.2 mu g/l for secondary and tertiary amines using a nitrogen-phosphorus de tector. Primary amines were detected at higher concentrations (from 10 mu g /l to 3000 mu g/l). This polar capillary column required the systematic add ition of ammonia to the sample (0.05 M concentration) in order to obtain a good repeatability (RSD=0.6-6.4%). This technique has been applied successf ully for the monitoring of amine concentration at sub-mu g/m(3) level in a compost treatment plant using absorption sampling in a hydrochloric acid so lution. (C) 1999 Elsevier Science B.V. All rights reserved.