Cryogenic Cooling Requirements; Using Carbon Dioxide - Agilent Technologies ALS Handbuch

6850 Series GC Site Preparation

Cryogenic Cooling Requirements

Cryogenic cooling allows you to cool the oven or inlet, including cooling to
setpoints below ambient temperature. A solenoid valve controls the flow of
coolant to the inlet or oven. The oven and inlet can use liquid carbon dioxide
(CO
If your application requires GC oven cryogenic cooling, contact your Agilent
sales representative.

Using carbon dioxide

Pressurized liquid CO
WA R N I N G
personnel from high pressures and low temperatures. CO
toxic to humans; take precautions to prevent hazardous concentrations. Consult
your local supplier for recommended safety precautions and delivery system design.
Liquid CO
should be free of particulate material, oil, and other contaminants. These
contaminants could clog the expansion orifice or affect the proper operation
of the GC.
Do not use copper tubing or thin-wall stainless steel tubing with liquid CO
WA R N I N G
harden at stress points and may explode.
Additional requirements for the liquid CO
• The tank must have an internal dip tube or eductor tube to deliver liquid
• Typical liquid CO
• Use 1/8-inch diameter heavy-wall stainless steel tubing for supply tubing.
98
) as a coolant.
2
is a hazardous material. Take precautions to protect
2
is available in high-pressure tanks containing liquid. The CO
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CO instead of gas (see the figure below).
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tank pressure will be 4830 to 6900 kPa (700 to 1,000 psi)
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at a temperature of 25 °C.
The tubing should be between 1.5 and 15 m (5 and 50 feet) long. (Agilent
part number 7157-0210, 20 ft)
in high concentrations is
2
system include:
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GC, GC/MS, and ALS Site Preparation Guide
2
. Both
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