Chromatographic methods for measuring impurities in a gas sample

Abstract From the Canadian patent

The present invention provides an improved chromatographic system and an improved chromatographic method for measuring impurities in a gas sample that advantageously allow to extract a peak of impurity masked by the sample background. The method extracts an impurities peak from the sample background and put it in a second sample loop. Then this second sample loop volume is injected into a second separation column. In fact the system takes a "slice" from the sample background and fills the second sample loop with it. Then the "slice", whose width is advantageously substantially equal to the impurities peak width is injected in the second separation column. In a further preferred embodiment …