Check out Safety Emporium for your N95, N99, and face shield needs.
Date: Wed, 17 Jun 2009 15:08:12 -0400
Reply-To: ILPI <info**At_Symbol_Here**ILPI.COM>
Sender: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
From: ILPI <info**At_Symbol_Here**ILPI.COM>
Subject: Re: Flash column chromatography
In-Reply-To: <F78074E5CA3141BBAA62B4610F31F723**At_Symbol_Here**AdminFin.ADS.umass.edu>
Disclaimer/whatever: my
company is a Chemglass (now Chemglass Life Sciences)
distributor.
There are older chromatography
columns out there made out of standard wall tubing. Flash
chromatography first came into vogue the late 1970's, so it's possible
you may have some thinner wall ones circulating at your organization.
A true flash chromatography column should be constructed out of
medium wall tubing to provide an extra margin of safety.
Chemglass not only makes theirs out of medium wall tubing, they are also
available from the factory with a clear plastic coating by special order
(if anyone wants quotes on these, contact me off
list).
Many columns use a fritted glass disc at
the bottom. The maximum differential pressure rating on those is
15 psi. So 15 or 20 psi should be established as the safe working
limit, yes.
Relatively safe pressure
control on columns can be achieved by making sure that the gas flow
control adapter at the top is not secured **too** tightly. A Keck
clip or such is more than enough to secure the adapter, but can still
provide some pressure relief. It is, of course, more
reliable and desirable to provide a pressure gauge and/or some sort of
relief system teed into the gas supply line so that researchers know
exactly how much pressure they are achieving. The best solution
would be a regulator can be used on the gas/air supply
line.
Your written SOP for chromatography
should include a discussion of the pressurization hazards, "safe"
pressure ranges, and how to mitigate the risks. The SOP should
also explain that proper PPE (lab coats with sleeves, goggles) and
engineering controls (fume hood sashes, blast shields etc.) can also go
a long way in minimizing any injury should an accident
occur.
Rob Toreki
On Jun 17,
2009, at 2:14 PM, Yung Morgan wrote:
Dear DCHAS
group,
I was wondering if
anyone had an idea or can direct me to literature on =93Flash
chromatography=94 whereby air is directed the solvent column to speed up
its elution of the compound wanted. One of our researchers had gotten a
cut from the glass column breaking and cutting him on the
arm.
Again, when asked,
he said: everybody uses this technique! Being an old analytical chemist,
I did not remember this method. However, an organic professor had
informed me that this method is also called =93Flash chromatography=94
and recommended the air pressure to be no more than 20PSIG and to wrap
the column in plastic tapes to protect from breakage! . The lab in
question use air spigots on lab benches which runs more than 20PSI if
fully opened.
Any thoughts or
comments you all have are welcome. Thank you in advance and enjoy your summer.
Yung
Morgan, MsPH
Laboratory Safety
Industrial Hygiene
Services
Environmental Health and Safety
117 Draper
hall
UMASS,Amherst MA 01003
phone (413)
545-2682
Fax (413) 545-2600
email : pmorgan**At_Symbol_Here**ehs.umass.edu