Thermo Scientific EA IsoLink IRMS System, Operating Manual, Page: 32 / 186

1
Getting Familiar with your EA IsoLink IRMS System for CNSOH
Instrument Basics
4 EA IsoLink IRMS System for CNSOH Operating Manual Thermo Scientific
• Adsorption filters — They can be made of glass or Plexiglas® according to the analytical
configuration.
• Reactors — The H and O configurations require the use of a special cylindrical ceramic reactor
filled with special catalyst.
There are two different sizes available:
−
reactor of 18 mm OD
−
reactor of 25 mm OD (Macro Reactor)

To set the temperature
The following procedure is recommended for heating up the furnace of the combustion reactor when
operating with chromium oxide (Cr
2
O
3
) at 1020°C:
1. Increase the temperature from room temperature to 400°C and check the background signals on
the Mass Spectrometer. Check the system for leaks.
2. Increase the temperature from room 400°C to 900°C in steps of 100°C and hold at 900°C for at
least 15 min. This avoids melting the copper within the reactor, which will cause poor
performance.
3. Increase it to the operating temperature of 1020°C..
• Protective Cap
Figure 1. Protective Cap
Note The EA IsoLink IRMS System for CNSOH comes standardized for a 18 mm OD
reactor. For 25 mm reactor tubes the MAS Plus and the top of the EA must be modified.
See the section
“Upgrading EA for 25 mm OD Macro Reactor” on page 133 .
WARNING Immediate temperature increase to 1020 °C can cause copper melting. Cooling down
in steps can avoid reactor breaking. Alternatively, you can use the HeatUp and CoolDown script in
Isodat. Right-click on the Flash IRMS visualization window in Isodat and choose the appropriate
context menu item. See
page 82 .
IMPORTANT Before the EA IsoLink IRMS System for CNSOH is shipped, the pneumatic circuit is
protected by a cap mounted on the coupling union located on the base of the left furnace
compartment as shown in
Figure 1 on page 4 . This is to avoid humidity in the chromatographic
column. The cap must be removed prior to the reactor installation.
Protection Cap
Coupling Union