Metrohm 850 Professional IC MSM-HC MCS Prep 3 - Manual (Page 117)

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
5 Operation and maintenance
850 Professional IC Anion – MSM-HC – MCS – Prep 3
￭￭￭￭￭￭￭￭ 107
5.13.3 Maintenance
5.13.3.1 Regenerating the MSM-HC
If the suppressor units are loaded for a longer period with certain heavy
metals (e.g. iron) or organic impurities, these can no longer be completely
removed with the regeneration solution (100 mmol/L H
2
SO
4
) normally
used. The capacity of the suppressor units is consequently affected, which
can result in reduced phosphate sensitivity in less serious cases and a sig-
nificant rise in the baseline in more serious cases. If such capacity prob-
lems occur at one or more positions, the suppressor units must be regen-
erated:
Regenerating the MSM-HC
1 Disconnecting the MSM-HC from the IC system
￭ Disconnect the MSM-HC from the separation column and MCS or
the detector.
2 Regenerating the MSM-HC
Caution
The pump tubings made of PVC must not be used for rinsing with
solutions containing organic solvents. In this case, other pump
tubings must be used for rinsing.
Note
The high pressure pump can be used for regeneration. For this,
remove the guard column and separation column and connect the
capillary directly to the MSM-HC (regenerate in opposite direction).
￭ Rinse the 3 suppressor units with the following solutions for
about 15 minutes each:
– Contamination with heavy metals:
1 mol/L H
2
SO
4
+ 0.1 mol/L oxalic acid
– Contamination with organic cationic complexing
agents:
0.1 mol/L H
2
SO
4
/ 0.1 mol/L oxalic acid / acetone 5%
– Severe contamination with organic substances:
0.2 mol/L H
2
SO
4
/ acetone ≥ 20%