David, and whom it may concern,
the phosphorus pentoxide from FLUKA I use is declared as "Sicapent", it
is Fluka-Nr. 79610 (approximately 20 US$ each 500 g). I always omit the
fine grainsizes and try to fill the water trap with coarse material to
keep the gas flow unhindered. An additional advantage concerning the
"storage bottle": you will easily notice any "deterioration" of your
P2O5 storage by the blue colour when moisture has been adsorbed ...
To Willi: I am an admirer of the Nafion dryers, too, but - even if I am
used to deal with molecules not visible to my eyes - I am happy to have
an clearly visible indicator whether water can reach the MS via the EA
or not ... Therefore I will stick to the ordinary water trap with
modified "innards". It takes less than 10 mins to clean and repack the
trap, and afterwards less than one hour purging time for the EA-MS
system - and is only necessary every 150-250 samples, so best combined
with the ash "vacuum cleaning" procedure ...
The only precaution I take for my personal safety is to wear gloves and
to try not to sniff P2O5 ...
With wishes for your EA-MS always keeping you smiling,
Christian.
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Christian Ostertag-Henning          tel: ++49-9131-852-2660 (office)
Institute of Geology                       ++49-9131-852-6243 (lab)
University of Erlangen-Nürnberg         fax: ++49-9131-852-9294
Schlossgarten 5
D - 91054 Erlangen                  email: [log in to unmask]

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