[Dolphinsiu]

When I do exam past paper, I get stucked with this question.

How could covalent organic bases (molecules) be separated with inorganic cations as shown in (B)? (3 marks)

(B) Order of elution in Chromatography
1. Monethanolamine
2. Diethanolamine
3. Triethanolamine
4. Magnesium
5. Calcium

Do anyone give some hints for me?

[Alpha-Omega]

I sure do. 

Separation of amines andd cations by IC using RFIC....this is a Dionex Application Note Update AU155.


Determination of Cations and Amines inHydrogen Peroxide by Ion ChromatographyUsing a RFIC™ (Reagent-Free) System.

Your matrix may not be H2O2 but it will work....

If you go to www.dionex.com....and type in amines and cations in the search field it will bring you to a number of literaature hits.  You could also type in AU 155 (with/without space).

If you read the note it takes you to the original AN (Application Note).

Here is the link to the AU 155.  it is a pdf....download it.

http://www1.dionex.com/en-us/webdocs/40541_AU155_V30_releasedJC082206.pdf