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Cameron Gren, University of North Alabama
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Last seen: 7 months 2 weeks ago
Joined: 05/11/2010 - 8:30pm

apparatus for sealing air-sensitive material into an ampoule

I work with air-sensitive organometallic compounds When I was in graduate school, we used to send off samples for x-ray crystallography in ampules that we would seal using a little apparatus. It was essntially a screw cap with a hole and an o-ring that you would put around the ampoule. That would then screw onto (I think) a threaded glass adapter with a ground-glass joint on the other end that you would put a gas inlet onto. All of this could be done in the glove box, then brought out and put on the Schlenk line. I seem to remember pulling a slight vacuum before sealing it. I'm guessing this was so the gas inside wouldn't expand and blow the seal out when flame sealing the ampoule.

I have tried to find an apparatus like this to order either intact or piece-by-piece (I have plenty of gas inlets), but I just can't seem to find the glass piece and the screw-down o-ring closure!!! Can anyone help me, please?

Kyle Grice, DePaul University
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Last seen: 2 hours 53 min ago
Joined: 07/22/2010 - 5:29pm

Hi Cameron,

 

Here's what I've been using for sealing NMR tubes:

https://www.wilmad-labglass.com/ProductList.aspx?t=446

You can also get ampules glass-blown onto 14/20 joints an use that.

A simpler approach would be to use thick rubber tubing between a closable 180 joint and the ampule. Set it up in the glovebox, bring out and then flame seal on the line.

Kyle 

Adam R. Johnson, Harvey Mudd College
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Last seen: 3 hours 25 min ago
Joined: 11/17/2007 - 10:55am

the valve you're looking for is a Cajon fitting from Swagelok. A quick search of their website did not turn anything up but you are looking for o-ring fittings. One side of this is correct. The glass piece is usually a ground glass stopcock terminating in 1/4" OD glass.

I actually stumbled on this page becasue I am trying (with little success) to seal my air sensitive samples in ampules using this exact fitting. I literally just got back from Lowe's with a small hand torch for finer control. wish me luck.

Adam R. Johnson, Harvey Mudd College
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Joined: 11/17/2007 - 10:55am