Hydrocarbon Losses on a Regenerated Nation® Dryer

In the gas chromatographic (GC) analysis of hydrocarbons in the ambient atmosphere, a Nafion® dryer was used in the sample preconcentration unit to remove moisture from the sample stream. We found that regenerating the Nafion® dryer by heating before analysis could cause losses and rearrangements of some hydrocarbon compounds in the sample. The degree of the losses and rearrangements was dependent on the length of time and the temperature used to regenerate the dryer, as well as the humidity of the sample. The effect of the regenerated dryer on the sample diminished when the dryer was purged with clean, dry nitrogen for several hours.