ACTSNYC@cs.com on tue 1 feb 00
In a message dated 1/31/00 3:28:14 PM Eastern Standard Time,
eiblodge@freenet.edmonton.ab.ca writes:
>
>
> help!!!!!!!!!
>
>
>
> ELKE BLODGETT email: eiblodge@freenet.edmonton.ab.ca
> 12 Grantham Place
> St. Albert, AB T8N 0W8
> 780 (458-3445);
>
> "Environmentalists make terrible neighbours but great ancestors."
> (David Brower, Sierra Club)
>
> ---------- Forwarded message ----------
> Date: Mon, 31 Jan 2000 14:43:56 EST
> From: Reid Harvey
> To: CLAYART@LSV.UKY.EDU
> Subject: making silver nitrate
> Resent-Subject: making silver nitrate
>
> ----------------------------Original message----------------------------
> Can anyone tell me the affects to the body of skin contact with salts of
> silver nitrate? While boiling silver ingots in nitric acid, I find it
> difficult to eliminate occasional contact with the salt. It seems that
> contact with skin (and just about anything else) ends up a bit like a
> photo emulsion, turning black, not wearing off the skin for a week or
> so. It appears important to keep everything very clean, knowing what is
> making contact with the salts, and gloves need to be taken off
> carefully, then washed.
> Reid Harvey
>
The black is the silver oxidizing under the skin. It has to grow out with
the new skin. But if you splash it in your eyes, its a different story.
Your cornea doesn't shed skin cells. People have been blinded or needed a
corneal transplant to see again after contact with silver nitrate.
The nitric acid also is a hazard as you well know. And there is no
respirator cartridge approved for it. The nitric acid and nitrogen oxides
created in this process can seriously and permanently damage your lungs. To
say nothing of eating your face.
And you are probably exposed to small amounts of silver in this process.
Silver is not very toxic in this form and it kind of travels around the body
looking for a good place to hang out. It often chooses the whites of the eye
or some other place to render you highly unattractive. I know of two
jewelers with this form of argyria.
I personally think there must be a better way to do this. And you should get
busy and try to find it.
Monona Rossol
ACTS
181 Thompson St., # 23
NYC NY 10012-2586 212/777-0062
ACTSNYC@cs.com
ACTSNYC@cs.com on wed 2 feb 00
In a message dated 2/1/00 2:23:09 PM Eastern Standard Time,
eiblodge@freenet.edmonton.ab.ca writes:
> ---------- Forwarded message ----------
> Date: Tue, 1 Feb 2000 14:17:37 EST
> From: ferenc jakab
> Reply-To: Ceramic Arts Discussion List
> To: CLAYART@LSV.UKY.EDU
> Subject: Re: making silver nitrate
> Resent-Subject: Re: making silver nitrate
>
> ----------------------------Original message----------------------------
> My father was a professional photographer for nearly 70 years. He did a 10
> year apprenticeship back when they had to make their own glass plates and
> mix their own chemicals. He did not suffer any problems until near the end
> of his life when his skin, particularly on his hands and arms became very
> sensitive to any chemicals he handled (rashes and sores), particularly old
> fixative which contains a lot of silver nitrate. Individuals vary greatly
in
> their sensitivity. I do not know what problems Medical science knows of.
> Feri
Old fixative contains silver all right, be not in the nitrate form. It is
washed out of the print by the acetic acid fix and is probably in a silver
acetate form. It is also unlikely that he was allergic to the silver
acetate. But small amounts of the washed out developer can be very
sensitizing as can the preservative which is a sulfite such as sodium
metabisulfite or sodium sulfite.
Skin and respiratory allergies are common in photographers. Your grand dad
was fortunate that it took so long for him to develop allergies.
Monona Rossol
ACTS
181 Thompson St., # 23
NYC NY 10012-2586 212/777-0062
ACTSNYC@cs.com
>
>
ferenc jakab on thu 3 feb 00
Monona,
Thank you for your reply and explanation. Thinking about it I should have
realised that the nitrate was removed during developing, which is why silver
is available in the fixer. I used to put copper coins into it and they would
become coated with silver. Once when someone tried to pass this off as a two
shilling piece in payment of the milk bill,the milk man became very irate
with my father and I received quite a hiding. Yes it was my father not my
Grand father. Additionally he finally realised why his fixer went off so
fast. I was a naughty boy at times.
Feri.
Elke Blodgett on fri 4 feb 00
> --------------------------Original message----------------------------
> Monona,
> Thank you for your reply and explanation. Thinking about it I should have
> realised that the nitrate was removed during developing, which is why
silver
> is available in the fixer. I used to put copper coins into it and they
would
> become coated with silver. <
This is the basis for silver recovery machines.
> Once when someone tried to pass this off as a two
> shilling piece in payment of the milk bill,the milk man became very irate
> with my father and I received quite a hiding. Yes it was my father not my
> Grand father. Additionally he finally realised why his fixer went off so
> fast. I was a naughty boy at times.
> Feri.
But I made a booboo in part of my answer to you. The silver is not in the
form of a soluble acetate! Bruce Girrell kindly reminded me that the silver
in the paper is in the form of a bromide that is converted to a soluble
compound by the hypo which is sodium thiosulfate. He even provided the
reaction which is:
AgBr + Na2S2O3 --> Na(AgS2O3)2 + NaBr
I have even written out this reaction in an article, but it was years ago and
I was not thinking when I answered!
Thank you Bruce.
Monona Rossol
ACTS
181 Thompson St., # 23
NYC NY 10012-2586 212/777-0062
ACTSNYC@cs.com
ACTSNYC@cs.com on sun 6 feb 00
>
> ---------- Forwarded message ----------
> Date: Fri, 4 Feb 2000 17:41:52 EST
> From: "I.Lewis"
> Reply-To: Ceramic Arts Discussion List
> To: CLAYART@LSV.UKY.EDU
> Subject: Making Silver Nitrate
> Resent-Subject: Making Silver Nitrate
> ----------------------------Original message----------------------------
> I have no doubt that silver can be reclaimed from photographic chemical
> residues ....<
Not only can it be, in the U.S. it must. Here in most U.S. cities and urban
locales, photographers have really only two legal options 1) purchasing one
of the silver recovery units on the market, or 2) having the waste picked up
by a disposal company that will recover the silver or dispose of it as toxic
waste.
> but I doubt very much that the Acid Bath which is used as an intermediate
> step
> ever reacts with either the developed silver or the undeveloped silver
> halides.
> It's purpose is to arrest the reactions by changing the developing
solution
> from
> a basic state to acidic. Sodium thiosulphate is then used to dissolve
> unexposed
> and undeveloped silver halides from the emulsion of the film. <
All I was commenting on the fact that the writer observed that a coin was
coated with silver when it was in the solution. And this demonstrates how
the commercial silver recovery processors work. The systems deposit the
silver on electrodes in much the same way only they speed up the electrolytic
process by adding current.
> Spent
> solutions
> should be returned to a refiner or professional chemical disposal unit for
> reclamation. In large operations the value of the reclaimed silver is
> significant and can be a valuable source of revenue which is all profit for
> processing labs. <
Absolutely a good idea. And how do you think they reclaim the silver?
> Making silver nitrate by reacting metallic silver with nitric acid is a
> dangerous process. Nitrogen dioxide which evolves is a corrosive gas brown
> red gas which causes severe irritation of the mucous membranes. This
reaction
> should be done in a fume cupboard. When handling concentrated acids wear
> appropriate protective clothing including a face mask. Before you start,
learn how to
> cope with an emergency situation. <
Here I completely agree. I think the person doing this is putting themselves
and others at serious risk. Dissolving an ingot of silver in concentrated
nitric acid is the dumbest way I've ever heard for obtaining silver nitrate.
The cost of installing the proper precautions for doing this safely will make
purchasing a bottle of silver nitrate from any chemical supply company look
cheap indeed.
You should be able to buy 250 grams for about $500 plus some special
shipping. The 250 grams is 99.999% pure and will last a LONG time. On the
other hand, the design and installation of proper ventilation, eye wash
fountains, and other safety supplies in the US. will cost between $10,000
and $20,000 in even a small studio with easy access to a suitable place to
exhaust. The cost of doing it without safety precautions could be life
itself.
> Best wshes to all for the New Year.
> Ivor Lewis.
Gung Hay Faut Choy 4698 to you, too!
Monona Rossol
ACTS
181 Thompson St., # 23
NYC NY 10012-2586 212/777-0062
ACTSNYC@cs.com
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