Technical Notes Anal. Chem. 1995, 67,3075-3078
Interaction of GaslPhase Organic Molecules with Aluminum and Electropolished Stainless Steel Tubing James J. F. McAndrew,* Dmity Znamemsky, David DeBord, and Ronald lnman Air Liquide, 5230 South East Avenue, Counttyside, Illinois 60525
The interaction of gas-phase species with metal surfaces is an important problem. In gas analysis, it atrects the delivery of atmospheric samples to analytical equipment through metal tubing and the storage of samples and calibration standards in cylinders and other containers. In this paper we describe a techniquefor injecting a pulse of gas with a parts-per-million (by volume) level of the molecule of interest into a stream of pure gas flowing through a sample of metal tubing. On the basis of the deformation of the pulse due to the tubing, the interactions between the tubing surface and the gas-phase molecule can be investigated. In the case of toluene interacting with electropolished stainless steel, for example, the degree of interaction is much less when the moisture concentration in the gas is 3 ppm than when it is
