Iron - Valence State Determination - HELP

[rubyfan]

We had recently considered purchasing an ICP-MS from Varian but we're afraid it won't give us the results we're hoping for... We produce glass capillaries, very similar to injector liners in terms of shape and size. We've already had an independent laboratory perform ICP-MS for us to determine total iron content in the glass. Now, what we'd like to know is the ratio of Fe2+ to Fe3+ in the glass. Does anyone have any suggestions?? We are afraid that sample preparation will change the oxidation state (i.e. putting the glass into an acid bath may oxidize more of the iron). Any thoughts?? We are really needing to know a rough estimate of the amount of Fe2+ to Fe3+ in our glass samples. Thanks to anyone who can help!!

-Aaron

[oscarBAL]

Hello rubyfan;
As far as I remember ICP it self convert all the Iron ions to elemental iron into the Plasm; ohter option it could be Ray-X.
Good technic, cheaper, but not so fast as ICP/MS could be voltammetry; but ofcourse you will have the same sample traetment problem.

Oscar.

[speciation]

you can try to use some base to solve it. Like KOH, or some other base, check with some sample preparation book, it should be a very basic method.