Metrohm 820 IC Separation Center - Manual (Page 45)

2.9 Separating columns and suppressor module
819 IC Detector / 820 IC Separation Center
37
2.9.3 Selection of the sample loop
Selection of the sample loop depends on the separating column used.
Normally, the following sample loops are used:
Anion columns 100 µ L
Cation columns 10 µ L
Columns for suppressor technique 20 µ L
Depending on the instrument version, the following sample loops are
installed in the 820 IC Separation Center:
Version Valve Sample loop Volume
2.820.0X10 A 6.1825.210 (PEEK) 20 µ L
2.820.0X20 A 6.1825.220 (PEEK) 100 µ L
B 6.1825.210 (PEEK) 20 µ L
2.820.0X30 A 6.1825.210 (PEEK) 20 µ L
If desired, the built-in sample loop can be replaced by one of the sam-
ple loops available as an option (see Section 6.3.1).
2.9.4 General information on suppressor module
The Metrohm Suppressor Module MSM for chemical suppression
installed in the 2.820.0X30 IC Separation Center comprises a total of 3
suppressor units which are in turn used for suppression, regenerated
with sulfuric acid and rinsed with water. To record every new chroma-
togram under comparable conditions, work is normally carried out with
freshly regenerated suppressor. Switching is either automatic together
with the valve switching or manual.
The suppressor units must never be regenerated with H
2
SO
4
in the
same flow direction used for the eluent. You should thus always install
the inlet and outlet capillaries as described in Section 2.9.7 according
to the scheme shown in Fig. 23.
For operation of the suppressor module, a two-channel peristaltic
pump is needed which conveys the regeneration solution (normally
50 mmol/L H
2
SO
4
) and the rinsing solution (normally dist. H
2
O) to the
suppressor units. We advise working with a flow rate of 0.5 mL/min.
The 2.833.0010 IC Liquid Handling Pump Unit is available from
Metrohm as an option. Two lengths of pump tubing (6.1826.050) are
enclosed with this pump (flow rate 0.5 mL/min). Startup and operation
of the 833 Pump Unit is described in the Instructions for Use enclosed
with the pump.
The three inlets and outlets numbered 1...3 on the suppressor module
each have 2 permanently mounted PTFE capillaries, which must be
connected as described in Section 2.9.7 (see Fig. 23 und Fig. 24).