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GCDetectors
DELCD -DryElectrolyticConductivityDetector
The DELCD is useful for low-level detection of chlorinated and brominated solvents in environmental
samplesandother traceanalyses. In thepictureabove, aDELCD ismountednext toFIDandPIDdetectors
on anSRI GC. The three chromatograms below are from a similar SRI GC.
The Dry Electrolytic Conductivity Detector possesses sensitivity much like the ECD, except it is more
selective to halogens and blind to oxygen. The SRI DELCD differs from the traditional wet ELCD in that
it does not use a solvent electrolyte or nickel reaction tube, and the reaction products are detected in
the gaseous phase. In the high sensitivity mode (no hydrogen, using dry tank air), the DELCD can detect
down to the lowpicogram range. In thismode, theDELCD is about 100 timesmore sensitive than the FID/
DELCD. However, the high sensitivity DELCD is susceptible to contamination from high concentrations of
chlorinated hydrocarbons and hydrocarbon solvents.
A 50ppb Japanese VOC
standard was placed into
a VOA vial with water, then
allowed to equilibrate at room
temperature for 45 minutes
before 1mL of the headspace
was injected. The FID
chromatogram shows all the
components and the solvent.
The DELCD does not respond
to the solvent, and the PID
doesnotdetect the1,1,1-TCA.
• Nonradioactivealternative toECD!
• HighSensitivity—Detectsdown to10ppb
• Selective toChlorinatedandBrominatedmolecules
• Best usedwithHeadspaceor Purge&Trap injectors
• CanbeCombinedwithFID, NPD, or TIDdetectors
DELCD FID
PID
FID
DELCD
PID
8690-1026
DELCDdetector
