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would this work? (are we wanting to get rid of calcium carbonate?)

updated sun 15 sep 02

 

Philip Poburka on sat 14 sep 02


Would Vinegar not dissolve it...and...?

Just a thought...

Phil
el vee

----- Original Message -----
From: "Ron Collins"
To:
Sent: Saturday, September 14, 2002 8:16 AM
Subject: would this work?


I know that I maybe should give up, but am not yet.
If I take the contaminated kaolin that melts at cone six, I
don't know exactly where, and contains, we think, large
amounts of calcium carbonate.
If I make little cones, and put them in firings at
different temps, and am able to determine the melting cone
temperature. I know that cone temps take more into
consideration, but let's forget about all that for the
moment.
THEN, take regular epk, and start adding increments of
calcium carb until I get the correct proportion that will
melt at the same temp as the above contaminated cone, will I
then have a sort of analysis of the percentage, which that
then could be put in a computer program and find out how
much silica to add to fully combine the calcium carb with
silica so that no extra lime/quicklime, calcium oxide,
calcia, whatever you want to call it, would be left over?
and then from that, with computer, know how much other
materials,etc to add to make a workable midrange cone 2-3
body that was in balance concerning the calcium carb.
I know it is not precise, but that might give us a rough
percentage of the whiting in the clay. Does that make any
sense?
Khaimraj Seepersad has helped me to understand the
problem thus far, and has given me some hope that there can
be a solution. So in the night, I thought of this....does
it make any sense ? Melinda Collins, Antigua Guatemala

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Gavin Stairs on sat 14 sep 02


At 05:50 PM 14/09/2002 -0700, Philip Poburka wrote:
>I have never worked with Hydrochloric Acid...but I am told
>one may wish to be especially careful...as stories I have
>heard, tell of getting it on one's hand or arm, and not
>feeling anything in particular.
>
>Later...one has an area of 'mush' as may have some
>tenderness...which shall need to be excised, leaving a
>cavity as may take prolongued convelescance to 'heal'...or
>more or less 'heal'.

I think your stories probably refer to some other, stronger acid. Nitric
usually stings, and it does have strong reactions with skin, including
brown staining and burning. Strong sulfuric acid will burn by removing
water and by corrosion, and can cause deep burns. Others, like
hydrofluoric acid and potassium permanganate, etc., have various peculiar
effects. What you are describing sounds like hydrofluoric acid. By
contrast, hydrochloric acid is relatively benign. It is usually classed as
a weak acid, but it is the strongest of the weak acids in ordinary use.

It should be treated with respect, especially in concentrated forms, but
not with paranoia. Just take care to wear protective gear, including face
mask and gloves, when handling the concentrated acid, dilute by adding acid
to water and not the other way around, keep it out of your eyes and don't
drink it. If you get splashed, wash it off with plenty of cold water, and
if a burning sensation persists, wash with a solution of baking soda or
some other weak base. If you spill acid on concrete or any other floor and
are worried about the finish, rinse with the same weak base solution. If
you spill concentrated acid, sprinkle with baking soda and flood with
water. The soda will fizz strongly and emit carbon dioxide. The residue
is a salt solution (NaCl). Do not add soda to any container full of strong
acid for fear of spattering. If you don't have any baking soda, soda ash
will do, but it has a risk of alkali burning (from pillar to post).

Gavin