Simon,
I don't recall having problems with the combustion in itself, neither
did I notice any unusual memory effect.
My experience is that you have to combust very low amounts of native
sulfur, because you get saturated signals on the mass spec very quickly.
If you want to calibrate your measurement against BaSO4 or Ag2S
materials for instance, you have to weight ~5 to 10 times less native S
in mass (a few tens of micrograms), and you also might have homogeneity
concerns at this level.
There should be one way around those two points, that would be to
'dilute' your native sulfur in a S-free combustion-helper powder. Of
course this requires to achieve a very homogeneous mix. I didn't
actually tried it myself.
Hope this helps
Nicolas Patris


Simon Poulson wrote:
>
> Has anybody here had any experience with trying to analyse d34S of
> native sulfur by elemental analysis-continuous flow isotope analysis?
> Someone has asked me about the possibility of running these analyses.
> I seem to recall that native S doesn't combust very easily, so I'm a
> bit concerned about the possibility that I'd get incomplete
> combustion and that the S would vaporize and then condense into the
> pipework further along the system.
>
> Cheers,
> Simon
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> Simon Poulson
> Dept. of Geological Sciences MS-172
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