Thermo Scientific EA IsoLink IRMS System, Руководство по эксплуатации

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6
Using EA IsoLink IRMS System for CNSOH
Measuring Sulfur Isotopes
Thermo Scientific EA IsoLink IRMS System for CNSOH Operating Manual 109
A slow stream of sulfur dioxide (SO
2
) through the system causes adsorption at the tubing wall.
Sulfur Measurement Kits
To perform a sulfur measurement your Elemental Analyzer needs to be modified. The required
hardware is available in a kit. This kit contains amongst some helpful chemicals and spare parts:
• a dedicated reactor
• a dedicated separation column for S analysis
• a special tubing to minimize water adsorption
Preparing the System for a Sulfur Measurement

To prepare the system for a sulfur measurement
1. Ensure proper ventilation by connecting the exhaust to an outlet.
2. Ensure heating of the pressure regulator for SO
2
.
3. Install the SO
2
GC column.
4. Installing the Self-Adhesive Heating Foil when using a ConFlo III.
a. Remove the backing paper from the self-adhesive heating foil.
b. Paste the heating foil in the middle of the manometer’s rear side (of Ref 2).
Note It is important that enough reduced copper (Cu) is present in the combustion tube.
If this is not assured, sulfur trioxide (SO
3
) will only be reduced partially and isotope fractionation will
occur.
Light isotopes (
32
SO
3
) are reduced more easily than heavy isotopes (
34
SO
3
). Therefore, sulfur
dioxide (SO
2
) gas is depleted in
34
S compared to the original sample, and the
δ
value becomes more
negative.
Table 22. Parts of Sulfur Measurement Kit for ConFlo (P/N 115 7100)
Quantity Description Part Number
1 Attachment for exhaust tube 112 1390
1 Self-adhesive heating foil for ConFlo 114 1180
1 Power supply for self-adhesive heating foil for ConFlo 204 8580
WARNING When working with sulfur dioxide (SO
2
), good ventilation is essential. Otherwise, the
gas can be hazardous to your health.
WARNING TOXIC SUBSTANCES HAZARD: To ensure operational safety, a CO, SO
2
and H
2
detector with an alarm must be installed. The exhaust tube should be installed on top of the ConFlo
interface to remove the toxic sulfur dioxide (SO
2
) from inside of ConFlo out of your working area.
See Figure 5 on page 8 .
Note SO
2
is liquid at higher pressures. Therefore, the manometer should be heated to avoid
condensation of SO
2
. The temperature must be between 60 °C and 70 °C. It may vary with
ventilation.