Product Manual for IonPac CS16
Page 31 of 65
5.8.
10,000:1 Ratio Sodium to Ammonium at 40 °C
A. CS16
5-mm
The following chromatograms show a ratio of 10,000:1 of sodium to ammonium on the CS16 5-mm using an isocratic eluent.
In cases where the sodium peak does not return to the baseline (see chromatogram A), it is recommended that a CTC-1 trap
column (P/N 040192) be placed between the CELL OUT and the suppressor REGEN IN ports (see chromatogram B).
Alternatively, the suppressor can be used in the External Water mode.
Column:
IonPac CS16 5-mm Analytical Column (no guard)
Sample Volume:
25 µL Loop
Eluent:
30 mM Methanesulfonic acid (MSA)
Eluent Flow Rate:
1.0 mL/min
Temperature: 40
°C
SRS Suppressor:
Cation Self-Regenerating Suppressor 300 (4-mm) in
AutoSuppression Recycle Mode
or MMS Suppressor:
Cation MicroMembrane Suppressor, CMMS 300 (4-mm)
MMS Regenerant:
TBAOH
MMS Mode:
Displacement Chemical Regeneration (DCR)
Expected Background Conductivity:
< 2 µS
Storage Solution:
Eluent
Figure 15a
0
2
4
6
8
10
0.20
0.22
0.24
0.26
0.28
0.30
0.32
1
2
0.20
µS
0.32
8
0
Minutes
2
4
6
10
A
Analytes:
mg/L (ppm)
1. Sodium
100.00
2. Ammonium 0.01
0
2
4
6
8
10
0.20
0.22
0.24
0.26
0.28
0.30
0.32
1
2
0.20
µS
0.32
8
0
Minutes
2
4
6
10
B
Analytes:
mg/L (ppm)
1. Sodium
100.00
2. Ammonium
0.01
Trace-level Quantification of Ammonium in Brine (10,000:1 ratio)
The conditions for the 6-Cation Fast Run, see
Section 5.6, “6-Cation Fast Run (Li
+
, Na
+
, NH
4
+
, K
+
,
Mg
2+
, Ca
2+
) at 40 °C,” can also be used for this
application, although the separation between sodium
and ammonium is not as good.
0
2
4
6
8
0.33
0.34
0.35
0.36
0.37
0.38
0.39
0.40
0.41
0.42
1
2
0.33
µS
0.42
8
0
Minutes
2
4
6
Analytes:
mg/L (ppm)
1. Sodium
100.00
2. Ammonium
0.01
Figure 16
Trace-level Quantification of Ammonium in Brine (10,000:1 ratio) Using the 6-Cation Fast Run
Document No. 031747-05
© 2010 Dionex Corporation
December 2010
