From: Monona Rossol <actsnyc**At_Symbol_Here**cs.com>
Subject: Re: [DCHAS-L] Devarda's Alloy
Date: Thu, 11 Jul 2013 19:31:25 -0400
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: 8D04CA5E4D9E538-136C-C5EC7**At_Symbol_Here**webmail-m210.sysops.aol.com
In-Reply-To <51DF1B7B.7010504**At_Symbol_Here**depauw.edu>


Almost all fine metal powders are potentially explosive in an enclosed container.  If someone shakes them up and there is  a static discharge, they can go up.  We have had bronze alloy pigments flash into flame being poured from one container to another.   I don't think I would be casual about the storage of metal powders.  Granted, the combination of being suspended in air and some kind of source of heat or electricity has to all come together just right.  But the potential is there.
 
Aluminum and magnesium are the most dangerous metals, but almost any metal can all go up with the right conditions. 
Monona Rossol, M.S., M.F.A., Industrial Hygienist
President:  Arts, Crafts & Theater Safety, Inc.
Safety Officer: Local USA829, IATSE
181 Thompson St., #23
New York, NY 10012     212-777-0062
actsnyc**At_Symbol_Here**cs.com   www.artscraftstheatersafety.org

 
-----Original Message-----
From: Dave Roberts <droberts**At_Symbol_Here**DEPAUW.EDU>
To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Sent: Thu, Jul 11, 2013 5:52 pm
Subject: Re: [DCHAS-L] Devarda's Alloy

I have a bottle or two of this stuff as well.  Mine is granular, and looks amazingly similar to my granular tin/aluminum/zinc or copper (it has a color to it - which just means there is some copper in the mix).  I assume it's not much different than any of my granular metals, so I just store it in a cabinet with them.  It is not flammable, and really these things are old enough that they aren't overly reactive.  It surely will not light unless you use a blow torch or something (and even then I'm not sure how easily it goes).  You probably have a 250g bottle or so (maybe more, I don't know).

I store it with my metals - which is away from any acids.  It will react with nitric acid (I tried once - just to see), just as copper does.  In fact one of the things I have done with it is to use in in a lab to determine the percent copper in the metal (by reacting with nitric acid and then quantitating the "blueness" of the solution with a spec of some sort).

Good luck

Dave





On 07/11/2013 02:20 PM, Ben Ruekberg wrote:
Here is my best guess.  I believe that Decarda's alloy is composed of (mostly) aluminum, copper and zinc.  Aluminum is apt to be the most reactive (and definitely should be kept away from caustics like sodium or potassium hydroxide and should probably be kept away from acids and oxidizers as well).  I would suggest that the question is one of particle size.  If you are talking about an ingot, you are probably pretty safe.  If you are talking about a fine powder, it is apt to be pyrophoric.  My suggestion, again a guess, would be to store it more or less as you would pure aluminum of the same particle size and away from acids because of the zinc.  At least until someone more authoritative comes along.
Thank you,
 
Ben Ruekberg
 
From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of Emily Coombs
Sent: Thursday, July 11, 2013 1:03 PM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: [DCHAS-L] Devarda's Alloy
 
We recently acquired some Dacarda's Alloy and are being faced with whether or not it needs to be stored in a flammables cabinet. We have not yet received an MSDS from the Manufacturer, and even just the NFPA ratings seem to vary incredibly. (Yes we are absolutely looking at the rest of the MSDS, but this provides a quick overview of how differently it is being presented in the different sources.)
From Sigma Aldrich (available from their site, but I am unable to attach here):
NFPA Rating
Health hazard: 0
Fire: 3
Reactivity Hazard: 3
From ScienceLab MSDS
http://www.sciencelab.com/msds.php?msdsId=9923683
Health: 3
Flammability: 1
Reactivity: 1
Specific hazard

From SIRI (not a source I would normally use, but is specifically listing the brand we have)
http://siri.org/msds/mf/baker/baker/files/d0776.htm
Health Rating: 0 - None
Flammability Rating: 1 - Slight
Reactivity Rating: 1 - Slight
Contact Rating: 0 - None

Can anyone shed any light on this particular materials' storage? It has caused some controversy here, and we would appreciate another perspective. Thank you!
 
Emily Coombs
Chemical Laboratory Manager
Simmons College
(617) 521-2725

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