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sodium carbonate glazing procedure

updated thu 2 sep 10

 

ivor and olive lewis on mon 30 aug 10


The travelling library confirmed my expectations.
Books by Gail Nichols and Ruthanne Tudball are not available in the South
Australian Public Library System.
Do either of these authors propose chemistries for the reactions that take
place when Sodium carbonate is used in the vapour glazing process ? I would
appreciate knowing their explanations if they give any.
Thank you ,
Ivor Lewis,
REDHILL,
South Australia

David Beumee on tue 31 aug 10


Hi Ivor,
Gail Nichols' book "Soda, Clay, and Fire" relies on Ruthanne Tudball's
acknowledgment of sodium hydroxide as an effluent gas of the introduction o=
f
a soda ash solution into a kiln, as well as depending on Ruthanne's argumen=
t
that "any sodium hydroxide emitted from the chimney would convert back to
sodium carbonate in the presence of CO2, and that the environmental effects
from a studio potter's soda kiln would be minimal."
Ruthanne Tudball's book "Soda Glazing" says of the introduction of a soda
ash solution that "sodium carbonate melts at 851 C and breaks down above
1000 C to give sodium oxide and carbon dioxide." Ruthanne's section on the
environment makes comparisons between the amount of CO2 produced by the
combustion of soda ash, sodium bicarb, salt, and natural gas to that of
adult breathing in a 24 hour period. She says "A small amount of sodium
hydroxide (caustic soda) may go up the chimney and either be deposited on
the cooler upper walls of the chimney or be exhausted. Any sodium hydroxide
particles emitted from the kiln will immediately combine with carbon dioxid=
e
in the moist air and drop to the ground in close proximity to the kiln.
Unless a large excess of Na2CO3 is used, these emissions are likely to be
very small indeed."

David Beumee
Lafayette, CO












On Mon, Aug 30, 2010 at 1:09 AM, ivor and olive lewis u
> wrote:

> The travelling library confirmed my expectations.
> Books by Gail Nichols and Ruthanne Tudball are not available in the South
> Australian Public Library System.
> Do either of these authors propose chemistries for the reactions that tak=
e
> place when Sodium carbonate is used in the vapour glazing process ? I wou=
ld
> appreciate knowing their explanations if they give any.
> Thank you ,
> Ivor Lewis,
> REDHILL,
> South Australia
>

ivor and olive lewis on wed 1 sep 10


David,
Thanks for that pr=3DE9cis.=3D20
I will try to construct equations for those potential changes and see =3D
what thermodynamic values evolve to support the notion of spontaneous =3D
and non spontaneous reactions.
Sincerely,
Ivor Lewis,
REDHILL,
South Australia=3D20
----- Original Message -----=3D20
From: David Beumee=3D20
To: ivor and olive lewis=3D20
Cc: Clayart@lsv.ceramics.org=3D20
Sent: Wednesday, September 01, 2010 6:54 AM
Subject: Re: Sodium Carbonate Glazing Procedure


Hi Ivor,
Gail Nichols' book "Soda, Clay, and Fire" relies on Ruthanne =3D
Tudball's acknowledgment of sodium hydroxide as an effluent gas of the =3D
introduction of a soda ash solution into a kiln, as well as depending on =
=3D
Ruthanne's argument that "any sodium hydroxide emitted from the chimney =3D
would convert back to sodium carbonate in the presence of CO2, and that =3D
the environmental effects from a studio potter's soda kiln would be =3D
minimal."
Ruthanne Tudball's book "Soda Glazing" says of the introduction of a =
=3D
soda ash solution that "sodium carbonate melts at 851 C and breaks down =3D
above 1000 C to give sodium oxide and carbon dioxide." Ruthanne's =3D
section on the environment makes comparisons between the amount of CO2 =3D
produced by the combustion of soda ash, sodium bicarb, salt, and natural =
=3D
gas to that of adult breathing in a 24 hour period. She says "A small =3D
amount of sodium hydroxide (caustic soda) may go up the chimney and =3D
either be deposited on the cooler upper walls of the chimney or be =3D
exhausted. Any sodium hydroxide particles emitted from the kiln will =3D
immediately combine with carbon dioxide in the moist air and drop to the =
=3D
ground in close proximity to the kiln. Unless a large excess of Na2CO3 =3D
is used, these emissions are likely to be very small indeed."

David Beumee
Lafayette, CO













On Mon, Aug 30, 2010 at 1:09 AM, ivor and olive lewis =3D
wrote:

The travelling library confirmed my expectations.
Books by Gail Nichols and Ruthanne Tudball are not available in the =3D
South
Australian Public Library System.
Do either of these authors propose chemistries for the reactions =3D
that take
place when Sodium carbonate is used in the vapour glazing process ? =3D
I would
appreciate knowing their explanations if they give any.
Thank you ,
Ivor Lewis,
REDHILL,
South Australia