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121
HeartCutTrapped inaLoop
and InjectedontoaSEcond
Column
Sample is injected (usinga separate
injector) ontoananalytical column. Early
elutingcomponents (front cut)pass
througha trapping loopandaredetected
(atport 3). Thevalve is then switched,
and thecenter (orheartcut)whichwas
retained in the trapping loop is injected
onto the secondcolumn to thedetector
(atport 4). Lateelutingcomponents (end
cut) are trappedon thefirst column. When
thevalve is switchedagain, theendcut
passes through the trapping loop to the
firstdetector,completing theanalysis.
TwoPositionApplications
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LoopSamplingwithTwoColumn
SequenceReversal
This is ideal forfixed-gas-from-CO
2
analysis
whereno“highboilers”arepresent.
Column1 ispackedwithaporouspolymer
andColumn2withmolecular sieve. The
sample loop is loaded inPositionA. When
thevalve is switched, the loopcontentsare
sentontoColumn1. As the inorganicgases
andmethane leaveColumn1andenter
Column2, thevalve is returned toPositionA,
reversing thecolumn sequence. CO
2
now
leavesColumn1,becoming thefirstpeak.
The inorganicsandmethaneare separated
by themolesieveandpass through the
porouspolymer column to thedetector.
10portcolumnswitching
SampleEnrichment (Cleanup)
UsingDualPrecolumns
Sample is injectedbya separate injector
ontooneof twoprecolumns (stripper).
Earlyelutingcomponentsvent atport 6
whilecomponentsof interest are retained
on the stripper. When thevalve is switched,
anew injection ismadeonto the second
stripperwhilecomponents retained
on thefirst stripper arebackflushed
onto theanalytical columnatport 9.
Note:
Thisapplication requiresanauxiliary
pumpatport 4.
10portcolumnswitching
10port sampling/switching
CHROMalyticTECHnologyPtyLtdAUSTRALIANDistributors e-mail:
: 03 97622034
