GAS-CHROMATOGRAPHIC ANALYSIS OF ALKANOLAMINE SOLUTIONS USING CAPILLARY AND PACKED-COLUMNS

The detailed analysis of amine solutions used in natural gas treatment is usually based on gas chromatographic (GC) methods which utilize columns packed with Tenax GC or TA, a porous polymer based on 2,6-diphenyl-p-phenylene oxide. This technique has the advantages of the ability to separate the various compounds in solution, minimum sample preparation and short analysis times. Advances in chromatography have shown the general superiority of capillary columns for the analysis of complex solutions. Unfortunately, Tenax is available only in packed columns. This paper presents the results of GC analyses of fresh and partially degraded alkanolamine solutions in which the Tenax column was replaced with a polyethylene glycol-based fused-silica, wide-bore capillary column (15 m x 0.53 mm I.D., 1.0-mum film thickness). It was found that the capillary column provides better peak shape, requires significantly less sample size, maintains higher sensitivity and offers a faster and more efficient separation than the Tenax packed columns.