Frontier EGA/PY-3030D, Руководство по эксплуатации

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Ver.1.36
5-5
5.3 DOUBLE-SHOT ANALYSIS
This is a two-step analysis in which volatiles are analyzed using thermal desorption technique, and the
residual polymeric fraction is then pyrolyzed. A typical instrument configuration for the Py-GC/MS is
shown in Fig. 5.1. The sample is the supplied polystyrene solution. The analytical conditions for
thermal desorption and flash pyrolysis are determined using the EGA thermogram shown in Fig. 5.6 .
STEP1 Install the separation column (contained in the package)
STEP2 Set the analytical conditions for the pyrolyzer and GC (see Fig. 5.8)
(1) Set the interface
temperature (ITF TEMP) to “Auto” mode.
(2)
Set the furnace temperature in “Double-Shot Analysis” screen.
STEP3 Loading sample
(1) Place 5 µL of the sample in an Eco cup LF and evaporate the solvent
(2) Attach a Double-Shot stick (Eco stick DF) to the sample cup and fix it to the sampler (Fig.
5.7A). Pull the slider of the sampler to the up position and attach the sampler to the
pyrolyzer (Fig. 5.7B). Loosen the air purge nut located on the side of the sampler and
leave it open for 2 min. Tighten the air purge nut before proceeding.
STEP4 Click the
“START” button when the temperatures and pressures are stabilized.
When the
“Ready for injection” dialog box is displayed, push the sampler slider all the way
down. This positions the sample cup in the furnace. Click the
“Start” button (Fig. 5.7C). The
thermal desorption program will start. Pull the sampler slider to the up position. When the TD
GC analysis finishes, the
“Prepare for pyrolysis step” dialog box is displayed. Click “Yes”
button to start the GC analysis.
Fig. 5.7 Sample introduction procedure for Double-Shot analysis
A) Attach sample cup to
the sampler with the
slider pushed down
B) Pull the sampler slider up
and attach the sampler to
pyrolyzer
C) Push the sampler slider down
to position the sample cup tin
the furnace.
Air purge nut