Metrohm 930 Compact IC Flex Oven/SeS/Deg - Manual (Page 44)

3.13 Metrohm CO
2
Suppressor (MCS)
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36 ￭￭￭￭￭￭￭￭
930 Compact IC Flex Oven/SeS/Deg (2.930.2460)
4 Connect the FEP tubing (6.1805.120) from the bottle with the rinsing
solution with the adapter Dosino Port 4/M6 to the Port 4 of the Dos-
ino.
If you would like to use a separate Dosino for the rinsing solution, you will
need the following additional accessories:
￭ Dosino (2.800.0010)
￭ Dosing unit 50 mL (6.3032.250)
￭ Accessory kit: Flex/Vario: ChS (6.5000.030)
￭ IC equipment: Dosino Regeneration (6.5330.190)
Connect the rinsing solution capillary with the Dosino and the bottle with
the rinsing solution as described in chapter Connecting the regeneration
solution to the Dosino, page 33.
3.13 Metrohm CO
2
Suppressor (MCS)
3.13.1 General information on MCS
NOTE
The Metrohm CO
2
Suppressor (MCS) is used only in conjunction with
conductivity detection with chemical suppression.
The Metrohm CO
2
Suppressor (MCS) removes the CO
2
from the eluent
stream. This lowers the background conductivity, improves detection sen-
sitivity and minimizes the injection peak and carbonate peak.
CO
2
can enter the eluent stream through the sample itself or can develop
due to the suppression reaction in the suppressor. Connecting the MCS
between the suppressor and detector minimizes the CO
2
peak in the chro-
matogram.
The MCS essentially consists of a degassing cell containing a capillary
made from a fluoropolymer membrane. The capillary is permeable to
gases. The degassing cell is connected to the vacuum pump. The eluent is
directed into the degassing cell through the capillary made of a fluoropol-
ymer membrane. At the same time, the vacuum pump generates a vac-
uum and draws in the air from the outside. The pressure and concentra-
tion difference this creates in the degassing cell relative to inside the capil-
lary causes the CO
2
to be diffused out of the eluent stream. The ambient
air is drawn in by a CO
2
adsorption cartridge that filters out the CO
2
.