Trace (low ppb) analysis for Bromide for seawater samples

[01310040231]

Hello:

I am being asked to test for bromide at less than 10ug/l in samples with about 0.5% chloride! Does anybody have any suggestions?

Thank you very much.

[iceyuser]

You might have a tough time with this. You probably don't want it to be this complicated but 2D(heart-cutting) techniques can help remove Cl from your final analytical column.

[M Farooq]

Hello:

I am being asked to test for bromide at less than 10ug/l in samples with about 0.5% chloride! Does anybody have any suggestions?

Thank you very much.

A high capacity IC column should be able to separate the overloaded Cl peak and the Br peak e.g. IonPac AS18 and IonPac AS23, but first check the response of 10 ppb Br alone. Try larger injection volumes as long as overloaded Cl does not interfere with Br and a decent signal for Br is visible. Most of the times you will a see fronted Cl overload peak, which means that later eluting peaks will not be drastically distorted if the Cl were tailing. Don't expect the same retention time of Br as under trace Cl conditions. The Br peak may shift earlier or even later under overload conditions.

[DJ]

Do you have a UV detector?

[James_Ball]

Hello:

I am being asked to test for bromide at less than 10ug/l in samples with about 0.5% chloride! Does anybody have any suggestions?

Thank you very much.

A high capacity IC column should be able to separate the overloaded Cl peak and the Br peak e.g. IonPac AS18 and IonPac AS23, but first check the response of 10 ppb Br alone. Try larger injection volumes as long as overloaded Cl does not interfere with Br and a decent signal for Br is visible. Most of the times you will a see fronted Cl overload peak, which means that later eluting peaks will not be drastically distorted if the Cl were tailing. Don't expect the same retention time of Br as under trace Cl conditions. The Br peak may shift earlier or even later under overload conditions.

You may also want to make your standards for Br into a solution of Cl that is near what you will find in your samples, this will help compensate for the overloaded conditions and give more accurate results.

What IC system are you currently using?

[H2Oh]

I second the 2D IC if you have the resources. We regularly run Br in brine samples so it can be done. I'm using Dionex ICs almost exclusively.