The Programmable
Temperature Vaporization (PTV) option adds ballistic heating capability
to the Heated Split/Splitless injector in order
to accommodate large volume injections and thermal desorption applications.
In the PTV mode, the insulation is removed from the Split/Splitless injector
so that the column oven fan can cool the injector down between analyses.
A small amount of
adsorbent material, like Tenax, is packed inside the PTV injector sleeve.
The initial column oven temperature, which maintains the injector cool-down
temperature, should be set slightly higher than the boiling point of the
solvent. As a large volume of sample is injected, the solvent vaporizes
and passes through the adsorbent material and out the split vent. The
split vent and carrier gas are under PeakSimple control. The carrier gas
can be turned OFF during the PTV ballistic heating, in order to preheat
the adsorbed analytes prior to desorbing onto the column.
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