Russel,
< /b>
& nbsp; The use o f a metal spatula was likely the factor causing the fire. LAH tend s to react with metallic apparatus to undergo a metal-ion induced decomposi tion. As the Al-H bond is much weaker than that of say the B-H bond i n sodium borohydride, LAH is much more reactive and readily gives up its proton. Metal hydride bonding characteristi c and thus reactivity vary from element to element as they behave as an all oy. Teflon or Teflon coated materials are a much better option for ha ndling reactives. I’m shocked the supplier was unaware of this.
< /b>
Best Regards,< /span>
& nbsp; & nbsp; Jim
< /b>
James A. Boehlert Jr.< /span>
Progr
am Manager - Chemical Safety
~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~
Princ eton University
Dept. of Environmental Health & Safety
262 A lexander Street
Princ eton, NJ 08540
~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~
609-2 58-7882 (voice)
609-2 58-1804 (fax)
< /p>
Lab Safety Training is requ
ired for all Princeton University researchers that work in a lab. Ple
ase register for training at
www.princeton.edu/training.
< /b>
From: DCHAS-L
Discussion List [mailto:DCHAS-L**At_Symbol_Here**LIST.UVM.EDU]
On Behalf Of Russell Vernon
Sent: Wednesday, June 29, 2011 8:13 PM
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Subject: [DCHAS-L] FW: Lithium Aluminum Hydride & friction as an
ignition source
Dear Chemical Safety Experts,< /span>
One of the labs on our campus had a fire when the researcher scraped lithium aluminum hydride (LiAlH4) ou t of the glass jar in which it was packaged. The LiAlH4 was old and the researcher was using a dry metal spatula. A quick review o f the manufacturer’s Material Safety Data Sheet informed the user of moisture sensitivity but there is no indication of friction causing a fire.
The supervising faculty member reported p ersonal knowledge that friction can cause ignition of LiAlH4.
The manufacturer (Sigma-Aldrich) of this material was contacted and responded:
From: Gregory Stachowiak [mailto:Gregory.Stachowiak**At_Symbol_Here**sial.com]
On Behalf Of Sigma-Aldrich Technical Service
Sent: Friday, June 24, 2011 8:17 AM
To: Russell Vernon
Cc: Chantalle Carver
Subject: RE: 199877 -- Lithium Aluminum Hydride
Hello again R ussell,
We do not have any data on-hand suggesting that friction alone c ould cause ignition, however, all of our handling of this chemical is perfo rmed inside a glove bag under a completely inert atmosphere (argon specifically). This inert atmosphere, combined with the idea that we don't "spread the product out over a large, flat, combustible surface" is likely why we have never had any issues with fires startin g during the packaging process.
As shown by those links, however, such an ignition does appear t o be possible. All we can recommend is handling this product under ar gon in a glove box or a glove bag to minimize the oxygen and moisture contact and therefore minimize the chances of a fire.
Unfortunately, because we have not had issues with this problem, we do not have a specific written procedure for weighing it, no.
Best regards,
Gregory Stachowiak
SIGMA-ALDRICH
Gregory Stachowiak
/
Scientist, Technical Service Associate
Technical Services
6000 N Teutonia Avenue / Milwaukee WI
53209
/ USA
P: (800) 231-8327, x5326 / G
regory.Stachowiak**At_Symbol_Here**sial.com
sigma-aldrich.com
http://cameochemicals.noaa.gov/chemical/989
http://www.chemicalbook.com/ChemicalPr oductProperty_EN_CB7318252.htm
http://www.erowid.org/chemicals/dmt/dmt_synthesis1 .shtml scroll do wn to step 3:
http://web.princeton.edu/sites/ehs/labs afetymanual/cheminfo/lah.htm
So it appears likely that friction alone in the presence of air may be able to ignite lithium aluminum hydride.
You may want to evaluate your own use and
written procedures to prevent this from happening in your world.
Sincerely,
-Russ
Russell Vernon, Ph. D.
Director
Environmental Health & amp; Safety
University of Californ ia, Riverside
900 University Ave
Riverside, CA 92521
russell.vernon**At_Symbol_Here**ucr.edu
Direct (951) 827-5119
Admin (951) 827-5528
Fax (951) 827-5122
http://www.ucop.edu/riskmgt/uctrips/
Previous post | Top of Page | Next post