Carbonate and Other Anions (1) (I-524A)

Standard anions (F^-, Cl^-, NO₂^-, Br^-, NO₃^-, HPO₄^2- and SO₄^2-) as well as carbonate were analyzed using IC I-524A. When an alkaline eluent is used, peaks of divalent cations (Mg²⁺, Ca²⁺) may interfere. In such instances, the sample must be pretreated using an Na⁺ type cation exchanger and the divalent cations in the sample replaced with Na⁺.
In case that the pH of the eluent is higher than 7.0, 10% methanol should be added to maintain the durability of the packing material.

(Preparation of eluent)
1) Put 0.207g of reagent grade p-hydroxybenzoic acid and 100mL of methanol into a messflask and dissolve.
2) Add pure water to make up a 900mL solution.
3) Add 7.9mL of 0.2M reagent grade diethylethanolamine.
4) Add purified water to make up a 1 liter solution.
5) Pass through a 0.2micron membrane filter before use.

(Remark): 0.2M diethylethanolamine should be kept in a refrigerator.


Sample :
1. F^-
2. HCO₃^-
3. Cl^-
4. NO₂^-
5. Br^-
6. NO₃^-
7. HPO₄^2-
8. SO₄^2-
AsO₄^3-
I^-
CrO₄^2-
S₂O₃^2-
WO₄^2-
MoO₄^2-
SCN^-

Column       : Shodex IC I-524A (4.6mmID*100mm)
Eluent       : 1.5mM p-Hydroxybenzoic acid(pH7.8 adjusted with N,N-Diethylethanolamine) + 10% CH3OH
Flow rate    : 1.2mL/min
Detector     : Non-suppressed coductivity
Column temp. : 40deg-C