Product Manual for IonPac CS16
Page 47 of 65
5.21.
Gradient Elution of Common Cations and Amines at 60 °C
Here a gradient of methanesulfonic acid from 6 mM to 60 mM was done with an Eluent Generator, EG40, on the 3x250 mm
high capacity weak carboxylic acid column at 60 °C. The analytes eluted are the common cations, lithium, sodium,
ammonium, potassium, magnesium and calcium, and are all well separated from the amines. Among the amines separated are
methylamine, dimethylamine and trimethylamine, and the more hydrophilic hydroxylamines ethanolamine, diethanolamine,
and triethanolamine. Besides ethanolamine, other power waters corrosion-prevention additives shown here are 5-amino-1-
pentanol (shown under these conditions partially coeluting with triethanolamine), morpholine and 2-diethylaminoethanol
(last eluting peak). The eluent contained no organic solvent, so the suppressor was used in the eluent recycle mode. The
suppressor was placed outside the chromatographic oven as the temperature exceeded 40 °C.
Column
IonPac CS16 3-mm Analytical Column (no guard)
Eluent
6 mM MSA, gradient from 0 to 13 min to
8 mM MSA, gradient from 13 to 25 min to
55 mM MSA, gradient from 25 to 30 min to
60 mM MSA
Eluent Source:
EG40
Flow Rate:
0.5 mL/min
Inj. Volume:
25 µL
Detection:
Suppressed conductivity
CSRS
®
300 2-mm outside oven
AutoSuppression
®
Recycle Mode
0
5
10
15
20
25
30
0.10
2.50
µS
1
2
3
4
5
6
7
8
9
1 0
1 1
1 2
1 3
1 4
15
Analyte mg/L
1. Lithium
0.05
2. Sodium
0.20
3. Ammonium
0.42
4. Ethanolamine
0.50
5. Methylamine
0.50
6. Diethanolamine
1.00
7. Potassium
0.50
8. Dimethylamine
1.00
9. Triethanolamine
18.00
10. 5-Amino-1-pentanol
2.00
11. Morpholine
2.00
12. Trimethylamine
1.50
13. Magnesium
0.25
14. Calcium
0.50
15. 2-Diethylaminoethanol
2.00
Figure 30
Gradient Elution of Common Cations and Amines at 60 °C
Document No. 031747-05
© 2010 Dionex Corporation
December 2010
