GC050 Detector Temperature

The detector and its connections from the column exit must be hot enough to avoid sample condensation but cool enough to not degrade the sample or the stationary liquid phase of the column. Peak broadening and loss of peaks due to condensation are a possibility at low detector temperatures.

Temperature control is dependent on the type of detector used. For instance, a thermal conductivity detector (TCD) needs to be controlled at ±0.1ºC or better to obtain good baseline stability and maximum detectivity. Flame ionization detectors (FID) do not need a strict temperature control. A temperature should just be high enough to avoid condensation of sample or water. A reasonable minimum temperature for an FID is 200ºC.

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