Dear Paul,

to circumvent these problems (which took us some time to pinpoint, too),
we pack our water trap with half magnesium perchlorate, half (in the
"downstream" direction) with phosphorus pentoxide dessicant with a
moisture indicator (from Fluka). This design has the advantage that you
easily can see how much capacity of your water trap is left , you can
measure the remaining lifetime (in samples) if you get a feeling for the
advance of the blue color towards the outlet - and you will always have
the possibility to change/repack the water trap before letting
substantial amounts of water in your MS system.
Have a nice day,

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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