From: Allen Niemi <anniemi**At_Symbol_Here**MTU.EDU>
Subject: Re: [DCHAS-L] Pyrophorics
Date: Fri, 25 Sep 2015 08:36:40 -0400
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: CAN0bzO7kvth5aK8Rc5aXfFXsuU53yG5Ef2FO4M31M-xYhSh0Vg**At_Symbol_Here**
In-Reply-To <012201d0f705$aa33c100$fe9b4300$**At_Symbol_Here**>

My guess is that this has not been well studied or published in general and, unless you are interested only in gases and liquids (vs mists or droplets), the limiting oxygen concentration can vary widely depending on particle/droplet size and particle shape (and temperature, of course). This is based primarily on my own experience with pyrophoric metal powders as well as some Bureau of Mines literature on combustible dusts I remember reading decades ago. Surface energy and reactivity is related to surface radius of curvature. For a beaker of liquid or very large droplets and gases, surface curvature has no real meaning.


On Thu, Sep 24, 2015 at 4:14 PM, NEAL LANGERMAN <neal**At_Symbol_Here**> wrote:

Does anyone have any citations for the low limiting oxygen concentration of pyrophoric compounds. I am specifically looking for the oxygen percentage at which compounds such as t-BuLi become non-ignitable. For example, that value is 5% for hydrogen. I have found a reference for silane, but, as is typical for silane, there are a myriad of confounding issues.

I have searched both SciFinder and Science Direct and have not found helpful data.




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