I don't think simply suggesting that a CSP sign off is a good way to go.
Many (most?) CSPs are not conversant with chemical reactions. I would
specify a CSP or a CIH with appropriate chemistry background, or perhaps a
Lab Safety person with appropriate chemistry background.

Peter Zavon
Penfield, NY

PZAVON**At_Symbol_Here**Rochester.rr.com

-----Original Message-----
From: ACS Division of Chemical Health and Safety
[mailto:DCHAS-L**At_Symbol_Here**PRINCETON.EDU] On Behalf Of Harrison, Paul
Sent: Sunday, October 14, 2018 5:14 PM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] sodium hydride solution

Certainly true. I would go so far as to say that if the researcher does not
understand this simple acid-base reaction that we would expect a student in
level 2 organic chemistry to understand, then they should not undertake the
process. The issue of scale also seems to have not even been considered:
this reaction will be exothermic and could run away if the scale is not
contemplated with relation to cooling the mixture.

My read of this is that the researcher is not a chemist. If so, then I
cannot emphasize enough that they should consult a chemist who has used
sodium hydride before, in advance of even buying it, and WELL before they
decide to clean up a spill with water! Believe it or not, many chemists
actually have training and expertise in handling dangerously reactive
substances such as hydrides, metals, alkyllithiums and so forth! As I like
to say, we don`t bite (very hard) and most chemists would (should) be
willing to assist a non-expert in performing this process safely.

I am wondering if a certified safety professional should have to sign off on
these substances, much like an engineer signs off that a bridge won`t
collapse.... In the current situation, I wouldn't drive across that bridge
until I had looked at it very carefully from all angles.

Paul
________________________________________
From: ACS Division of Chemical Health and Safety [DCHAS-L**At_Symbol_Here**PRINCETON.EDU] on
behalf of davivid [davivid**At_Symbol_Here**WELL.COM]
Sent: October 11, 2018 12:17 PM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] sodium hydride solution

Ellen

I don't know what reading is being referred to here, but I think there
may have been some miscommunication. Sodium hydride will certainly react
with 2-propanol. In fact, it is a good base to use to generate solutions
of alkoxide. The sodium hydride is insoluble, reacting at it's surface
to deprotonate the alcohol and generate the alkoxide.

See for example...
https://www.masterorganicchemistry.com/2014/10/24/the-williamson-ether-synth
esis/

Sodium hydride is usually supplied as a dispersion of the solid in
mineral oil to avoid reaction with atmospheric moisture. See the
following for usage...

https://onlinelibrary.wiley.com/doi/10.1002/9780471264194.fos09197.pub4

https://pubs.acs.org/doi/abs/10.1021/op200114t?src=recsys&journalCode=oprdfk

I hope this helps

Dave Lane
Principal
Clavis Technology Development

On 10/10/18 12:39 PM, Ellen M. Sweet wrote:
> Hi everyone,
> I have a researcher who is proposing to make a solution of 2-propanol and
sodium hydride.
>>From what I'm reading the NaH will not react with the propanol, but that
this needs to be done slowly and under nitrogen.
>
> Any suggestions on what this setup would like and how to add the NaH?
> Thanks in advance.
>
> Ellen
>
> Ellen Sweet
> Laboratory Ventilation Specialist
> Department of Environmental Health and Safety, Cornell University
> American Chemical Society, Division of Chemical Health and Safety
> 315-730-8896
>
>
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