Trace Impurities in Bulk Gases

Trace level detection of impurities in inorganic gases is crucial for the bulk gas and semiconductor industries. Analysis of impurities in hydrogen is traditionally performed in conjunction with a palladium diffusion tube to eliminate the bulk hydrogen peak. This analysis, performed on a Valco Trace Gas Analyzer (TGA) equipped with the PDD, eliminates the palladium tube and highlights the sensitivity and stability (fast recovery from the bulk peaks) of the PDD.

chromatogram of trace impurities in bulk gases
Run conditions
Sample 250 µl of 2 ppm permanent gas blend in bulk hydrogen
Detector mode Helium photoionization
Discharge gas Helium
Dopant gas None
Detector temp 100°C
Column Heartcut Molesieve 5Å, 10' x 1/8"
Analysis Molesieve 5Å, 10' x 1/8"
Column temp 100°C