Stable Isotope Geochemistry


Options: Use Forum View

Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
"Haraldur R. Karlsson" <[log in to unmask]>
Reply To:
Stable Isotope Geochemistry <[log in to unmask]>
Tue, 21 Oct 1997 17:22:48 -0500
text/plain (49 lines)
>Dear Peter and others interested,
>As others have already mentioned, I believe, it is usually preferable to
>have the bottom cut of the Kel-F finger to be of a different shape than the
>standard V- or square-shape of the cutting tool. A spherical end is reputed
>to produce less stresses within the kel-F tube.
>If Peter would give is optimal cooling mixture for BrF5 distillation, I am
>sure that several of us will be interested. I guess it is so simple to use
>LN that you do not think of a lower temperature coolant.
>As for thawing, I have been warming the Kel-F tube slowly with a heat gun.
>In partice, we place the heat gun about 2 feet below the tube and blow warm
>air arond the length of the tube. This should be less stressing than the
>water bath... but still must introduce temperature gradients (and
>stresses?) into the tube. My experience is for a period of 4 years without
>noticeable deterioration, but Peter's adventure is well noted! Anybody else
>experienced with the warm air cooling that could give feedback?
>Dr. Georges Beaudoin
>Département de géologie et de génie géologique
>Université Laval
>Québec, Québec
>G1K 7P4
>tel.: 1-418-656-3141
>fax.: 1-418-656-7339

Dear all,

We use dry ice for BrF5 purification just like I learned in Clayton's lab.
There is no need to use a heat gun or water beaker to thaw the BrF5 because
it usually has warmed up enough when we are finished loading our samples.

Best wishes,


Dr. Haraldur R. Karlsson
Associate Professor of Geosciences
Deptartment of Geosciences
Texas Tech University
Box 41053
Lubbock, TX 79409, USA

(806)-742-3130 voice
(806)-742-0100 fax