Anion Standards (19) (SI-90 4E)

Anion standards were analyzed using IC SI-90 4E (a column for anions analysis). For general-purpose, it is recommended to use 1.8mM Na₂CO₃ + 1.7mM NaHCO₃ as the eluent. This eluent is best suited to the separation of typical 7 anions:

F^–,Cl^–,NO₂^–, Br^–,NO₃^–,PO₄^3-,SO₄^2-.

Using the flow rate of 1.5 mL/min, seven anions can be analyzed within ten minutes.
Use the column temperature of 25°C.

How to prepare the eluent

(1) Put 19.08g of reagent grade Na₂CO₃
and 14.28g of reagent grade NaHCO₃ into a 1 liter messflask.

(2) Dilute with purified water to make up a 1-liter solution.

(3) Dissolve the solution using an ultrasonic vibrator.
When the solution volume decrease after the vibration,
add pure water to make up the exact 1-liter solution.
This is the concentrated solution and can be stored
for half a year in a refrigerator with a stopper.

(4) When making the eluent, take 10ml of the concentrated
solution and dilute with purified water to make up a 1-liter solution.
Pass the eluent through a 0.45micron membrane filter before use.

 Column : Shodex IC SI-90 4E (4.0mmID*250mm)
 Eluent : 1.8mM Na2CO3+ 1.7mM NaHCO3 aq.
 Flow rate : 1.0mL/min or 1.5mL/min
 Detector : Shodex CD-5 and Suppressor module
 Column temp. : Room temp. (25°)