Agilent Technologies 6890 Series Service Manual page 466

520 Gases
Gas requirements
Gases for packed columns
The carrier gas you use depends upon the type of detector and the
performance requirements. Table 520-1 lists gas recommendations for
packed column use. In general, makeup gases are not required with packed
columns.
Table 520-1
Detector
Electron Capture
Flame Ionization
Flame
Photometric
Nitrogen-
Phosphorus
Thermal
Conductivity
Note A: Slightly greater sensitivity than helium. Incompatible with some compounds.
Note B: For analysis of hydrogen or helium. Greatly reduces sensitivity for other compounds.
Jun 2001
Gas Recommendations for Packed Columns
Carrier Gas Comments
Nitrogen Maximum sensitivity
Argon/ Maximum dynamic range
Methane
Nitrogen Maximum sensitivity
Helium Acceptable alternative
Hydrogen
Helium
Nitrogen
Argon
Helium Optimum performance
Nitrogen Acceptable alternative
Helium General use
Hydrogen Maximum sensitivity (Note A)
Nitrogen Hydrogen detection (Note B)
Argon Maximum hydrogen sensitivity
(Note B)
Site Preparation
Agilent 6890 Gas Chromatograph Service Manual
Detector anode purge
or reference gas
Nitrogen
Argon/Methane
Hydrogen and
air for detector
Hydrogen and air for
detector
Hydrogen and
air for detector
Reference must be same as
carrier
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