Butch Welch on fri 23 may 03
Wanda,
Be very careful with the mixture you have made. I will post a link to the
MSDS(material safety data sheet) for both chemicals.
Vanadium pentoxide is a extremely toxic chemical by itself. It is incapable
with acids as you can read on the link.
http://physchem.ox.ac.uk/MSDS/VA/vanadium_pentoxide.html
Lithium Carbonate I take is an acid based on the general synonyms listed for
it, (carbonic acid lithium salt)
http://physchem.ox.ac.uk/MSDS/LI/lithium_carbonate.html
That is why you got a chemical reaction.
I am no chemist, but I would consult with one on how to dispose of solution
you have made. I would definitely not touch it with bare hands, or breathe
it in any way.
Regards, Butch
PS- any time you have a chemical you are uncertain about, do a search on
yahoo, for the chemical name and look for a link to a material safety data
sheet. This is something that should be supplied with each shipment of any
chemical. I am surprised at being able to buy chemical at pottery suppliers
without them. In industry you can not receive any chemical or ship any
chemical with an MSDS attached,
It provides all the safety data you need to handle the product.
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG]On Behalf Of Wanda Holmes
Sent: Friday, May 23, 2003 3:21 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Chemical reaction in my glaze slurry
I have just been testing color response in the following base glaze and
had a very interesting thing happen. When I added 10% vanadium
pentoxide to the base glaze, a chemical reaction was initiated and the
slurry began to 'boil'. What happened? Is it dangerous? I put it
outside just in case and I have not covered it so that the gas being
formed can escape. It's still bubbling.
Wanda
Frit 3110 19
Frit 3289 33
Whiting 9
Lithium carbonate 4
EPK 13
Silica 22
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Wanda Holmes on fri 23 may 03
I have just been testing color response in the following base glaze and
had a very interesting thing happen. When I added 10% vanadium
pentoxide to the base glaze, a chemical reaction was initiated and the
slurry began to 'boil'. What happened? Is it dangerous? I put it
outside just in case and I have not covered it so that the gas being
formed can escape. It's still bubbling.
Wanda
Frit 3110 19
Frit 3289 33
Whiting 9
Lithium carbonate 4
EPK 13
Silica 22
David Hewitt on sun 25 may 03
Wanda,
I wonder if you have ammonium metavanadate (NH4VO3).
I have recently been testing both vanadium pentoxide (V2O5) and vanadium
trioxide (V2O3). I have not experienced any bubbling or gassing with
either of these. I read, however, in Ceramics Glaze Technology by J.R.
Taylor and A.C. Bull that another source of vanadium is ammonium
metavanadate and it says:-
"An alternative source of vanadium is the precipitated salt of ammonium
metavanadate. When used as a mill addition it is the source of much
reactivity in the molten glaze. It dissociates at 210oC."
I know that it says 'in the molten glaze' and you are talking about room
temperature but I do wonder what it does at room temperature when mixed
with just water. Have you tried just mixing some of your material with
just water? Does the gassing that you are getting smell of ammonia?
I would also go back to your supplier and ask him for an analysis of
what he has supplied to you. As I said, from my experience, I would not
expect you to get this bubbling and gassing result from either vanadium
pentoxide or trioxide.
David
In message , Clayart writes
>I have just been testing color response in the following base glaze and
>had a very interesting thing happen. When I added 10% vanadium
>pentoxide to the base glaze, a chemical reaction was initiated and the
>slurry began to 'boil'. What happened? Is it dangerous? I put it
>outside just in case and I have not covered it so that the gas being
>formed can escape. It's still bubbling.
>
>Wanda
>
>Frit 3110 19
>Frit 3289 33
>Whiting 9
>Lithium carbonate 4
>EPK 13
>Silica 22
>
>____________________________________________________________________________
>__
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at
>melpots@pclink.com.
--
David Hewitt
David Hewitt Pottery
7 Fairfield Road, Caerleon, Newport,
South Wales, NP18 3DQ.
Tel:- +44 (0) 1633 420647
Fax:- +44 (0) 870 1617274
Web:- http://www.dhpot.demon.co.uk
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