Light bulb test for O2 in a glove box...
Like a patient etherised upon a table
I am refurbishing a glove box whose oxygen sensor is FUBAR'ed. I
remembered that a light bulb, with a hole filed into it, can be used as an
ersatz O2 sensor. Trouble is, I cannot find any specific info regarding
that technique on the web, or using my cursory lit searching techniques
(SciFinder, WebOfScience). Does anyone know how to do this test or where
I can find some info on it?
Thanks.
Michael Stewart
email to: stew...@omni.cc.purdue.edu
Uncle Al
>
> Hi all,
>
> I am refurbishing a glove box whose oxygen sensor is FUBAR'ed. I
> remembered that a light bulb, with a hole filed into it, can be used as an
> ersatz O2 sensor. Trouble is, I cannot find any specific info regarding
> that technique on the web, or using my cursory lit searching techniques
> (SciFinder, WebOfScience). Does anyone know how to do this test or where
> I can find some info on it?
You take a 100 watt lightbulb and break its envelope without
damaging the filament. You lighty screw it into a socket in the
glovebox. If it stays lit for a few days you have a clean
atmosphere. (If you are under helium the high thermal
conductivity of the gas will substantially reduce filament temp).
A faster check is to cut a piece of sodium. If it stays mirror
shiny you are in business.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!
Dr. Artem Evdokimov
> shiny you are in business.
Or use an organozinc compound - if it fumes or lights up then you either
have oxygen or water vapor.
A.
--
|Dr. Artem Evdokimov Protein Engineering |
| NCI-Frederick Tel. (301)846-5401 |
| FAX (301)846-7148 |
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Bill Walker
That would be a pretty fast and definite check, wouldn't it? :)
Bill
Uncle Al
Have you ever worked with it? The stuff evaporates like water.
You'd never get rid of it except by grunging the box.
Jeff Harlan
will pop when it melts, then screw it in to a socket in the box. A light
bulb will burn for many days if the atmosphere is good. However, the
presence of organic solvent vapors will cause the filament to burn out
really quickly, even if there is very little O2. Since I use organic
solvents in my box I typically use use trimethyl aluminum or diethyl zinc
(as suggested by others), when the atmosphere is good, these materials
produce almost no smoke.
Jeff Harlan
Department of Chemistry and Geochemistry
Colorado School of Mines
"Like a patient etherised upon a table" <stew...@omni.cc.purdue.edu> wrote
in message news:9kmtln$1sk$1...@mozo.cc.purdue.edu...
Hiroshi Ogura
>shiny you are in business.
There is yet another method. This one is colorimetric. In the glove
box, you shake Cp2TiCl2 (bis(cyclopentadienyl)titanium dichloride, $24
per 10 g from Aldrich) with zinc dust and acetonitrile to form
[Cp2Ti(3+)(NCCH3)2]+, which is deep blue. You leave the solution in
an open vial in the box. If the glove box is O2-free, the color
remains blue. If there is a trace of O2 in the box, this complex
oxidizes to [Cp2Ti(4+)(NCCH3)2]2+, which is yellow. For details, see
Burgmayer, S. J. N. _J. Chem. Ed._ 1998, 75, 460.
As you can see, there are all sorts of methods. Choose one with which
you'd feel comfortable.
--
Hiroshi Ogura | One man, he drinks up his whiskey;
Dept. Chem., Univ. Ariz. | Another, he drinks up his wine.
Tucson, AZ 85721 | And they'll drink till their eyes are red with hate
hir...@u.arizona.edu | For those of a different kind. -- Richard Thompson
Like a patient etherised upon a table
>>shiny you are in business.
>
>There is yet another method. This one is colorimetric. In the glove
>box, you shake Cp2TiCl2 (bis(cyclopentadienyl)titanium dichloride, $24
>per 10 g from Aldrich) with zinc dust and acetonitrile to form
>[Cp2Ti(3+)(NCCH3)2]+, which is deep blue. You leave the solution in
>an open vial in the box. If the glove box is O2-free, the color
>remains blue. If there is a trace of O2 in the box, this complex
>oxidizes to [Cp2Ti(4+)(NCCH3)2]2+, which is yellow. For details, see
>Burgmayer, S. J. N. _J. Chem. Ed._ 1998, 75, 460.
>
>As you can see, there are all sorts of methods. Choose one with which
>you'd feel comfortable.
Thank you for all of your help. I will look into the colorimetric test as
it appears to be best candidate. I know of the organometallic tests like
diethylzinc and methylaluminum, but this is supposed to be a materials box
so the contamination might become an issue. The light bulb burned for
about 3 hours before going out, so I imagine that solvents or O2 are
present. Some glove boxes I have seen (not this one) are worse than
superfund sites.
m
|Dr. Michael P. Stewart |<yo...@purdue.edu>|<omni.cc.purdue.edu/~stewarmp>|
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