David,

I would scrub the vessels with a brush (preferably copper) to remove excess
fluoride coatings, remove dust with a vacuum cleaner (or dump it out), then
run them as blanks with reagent only, heating them for at least 12 hours.
Monitor your residual gas yield at LN2 temperatures after the heating
period. For good vessels there should be little or no residual pressure.
Repeat the blank run (not the scrub-out) if this is not the case. Some
vessels may take a number of runs like this before the residual pressure
approaches background values. Then run some in-house mineral standard.

Greetings,

Torsten.


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Torsten W. Vennemann
Institute for Geochemistry
University of Tuebingen
Wilhelmstr. 56
72074 Tuebingen
Germany

Tel: (0)7071 29 74992
Fax: (0)7071 29 6870
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