Multiple Headspace Extractions; Concentrated Headspace Extractions - Agilent Technologies 7697A Advanced Operation Manual

2
How the 7697A Headspace Sampler Works

Multiple headspace extractions

Concentrated headspace extractions

24
from it according to the method parameters. See
and Figure 9. After any sample loop equilibration, the HS six
port valve switches to the inject position, the HS injects the
sample, and the HS sends a Start command to the GC. At
the same time, the HS vents residual pressure from the vial
(optional). After the inject time elapses, the six port valve
returns to its original position. The sample vial is removed
from the probe and returned to the carousel or tray.
In this mode, the HS performs multiple extractions and
injections using one vial puncture. See
Figure 9. After the vial equilibrates, the HS checks system
readiness. If the system is ready, or if the readiness
sequence action is continue, the HS punctures the vial. The
HS pressurizes the vial and extracts the sample from it
according to the method parameters. The sample loop vent
closes. The vial remains on the probe. After any sample loop
equilibration, the HS six port valve switches to the inject
position, the HS injects the sample, and the HS sends a
Start command to the GC. At the same time, the HS vents
residual pressure from the vial (optional). After the inject
time elapses, the six port valve returns to its original
position. The vial remains on the probe. When the GC Cycle
time elapses, the HS again checks the readiness of the
system. If the system is ready, or if the readiness sequence
action is continue, the HS performs the next pressurization,
extraction, injection, and start run. The process repeats until
all extractions and injections have been performed.
After the final extraction and injection, the sample vial is
removed from the probe and returned to the carousel or
tray.
Use this mode to concentrate sample in the GC. Typically
this mode requires a sample concentrating trap of some
kind. (The trap could be an optional external device or an
inlet such as the Agilent Multimode inlet.) See
Figure 9.
After the vial equilibrates, the HS checks system readiness.
If the system is ready, or if the readiness sequence action is
continue, the HS punctures the vial. The HS pressurizes the
vial and extracts the sample from it according to the method
parameters. The vial remains on the probe. After any sample
Figure 8
Figure 8 and
Figure 8 and
Advanced Operation