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Panache
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Polaroid Film and Silver recovery
As part of my recent haul of ex-lab gear i have 60 boxes of 20 sheets so thats 1200 polaroid films, out of date and in medium format so the only use i
can see is getting the silver halides out of them. Is there going to be enough to bother with?
Would firing the whole shebang in my furnace at say 850C leave me with only the stainless (from the film frames) and silver or would the silver salts
volatilise largely before they were reduced.
I'm fairly inorganic inept so any theorising would be welcome.
Also i have something funny to report.
If you type UTFSE into the search engine it opens a portal in your screen to another dimension and Tom Cruise is there!!!! Kinda like what happens
when you type google into google, except that Ghandi's brother Billai is there naked dancing with John Travolta Saturday Night Fever Style, weird. But
the vegetarian snacks were awesome.
[Edited on 22-2-2008 by Panache]
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a_bab
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First you have to compute the total amount of silver from these sheets. Usually it averages between 1-3 grams/square meter for color paper; a roll of
film with 24 positions would hold as much as 0.25 grams of pure silver. So I'd say that you'll get under 3 grams of silver/square meter.
The burning of these sheets would give you ashes that are silver rich; that was the preffered method for silver recovery from old films. It was
abbandoned by kodak back in the '60 due to enviromental concerns.
Besides your sheets contain the fixer and the developer so the fumes are to be even more toxic.
If you need silver try to get some spent fixer and reduce it as I do. You'll get at least 3 grams/liter (up to 10 grams).
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woelen
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The amount of silver on film and foto paper is amazingly small. I even think that a_bab is optimistic with his estimates. The cost of recovering
those few grams (at most) from all these ashes and other crap is much more than the cost of simmply buying some very pure silver metal. Silver
granules and bullions can be obtained from eBay for $20 per ounce or something like that.
Quote: | Also i have something funny to report.
If you type into the search engine it opens a portal in your screen to another dimension and Tom Cruise is there!!!! Kinda like what happens when you
type into google, except that Ghandi's brother Billai is there naked dancing with John Travolta Saturday Night Fever Style, weird. But the vegetarian
snacks were awesome. | Should the entire post go to detritus for this reason?
Stop adding unneccessary noise to the forums. I have seen enough of that from you .
[Edited on 22-2-08 by woelen]
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a_bab
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Well, he'd better stop smoking crap I'd say. Or stop the crap all in all.
On the other hand, I wanted to open a topic for silver recovery from spent fixer, but now that this is open let's discuss here the ideas, results,
etc. Generally speaking, silver is not THAT expensive as a metal, but the prices are going higher and in some cases it could be difficult for the
amateur chemist to aquire it besides ruining the mothers jewelries (as I did when I was young and *stupid*).
The prices for a silver troy ounce is rougly 15 US dollars now; it used to be around 7 some years ago and God knows how much would it be in the
future.
As I said, for 3-10 grams of silver in the spent fixer it could get really interesting to get some fxer for the silver recovery. The richest fixer
comes from b&w films, and the best source of it are the hospitals that do X rays films. They could produce literally tens of gallons/month
(meaning kilos of silver/year).
The fixer in nothing but a thiosulfate solution that has silver disolved it it, besides some other chems.
There are several methods for getting the silver out of thiosulfate; the "classical" one is the reduction of silver with the more active metals and
iron wool is the choise for the comercial recovery. Other metals would work aswell like copper, zinc, etc.
The electrolysis is another method; the problem is that it produces toxic and stinky SO2 fumes.
Another method is the chemical reduction with things like HNO3 (a fast method), or H2O2. These all produce foul smels, so they are not good for home.
Personally, so far the Al sheet method is the best as it produces no smells, and it's fairy fast (complete pp of the silver within 3 days). I'll get
back with pics soon.
Panache, please stay out and smoke your stuff unless you have something to contribute. Somebody from another dimension just hijacked your thread ![:D](./images/smilies/biggrin.gif)
Other methods/ideas are welcome so please contribute.
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Panache
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so i'll toss the film i guess, seems a waste, oh well.
Apologies for being divergent in my posting, i'll keep it on topic from now on (shit i just did it again lol)
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YT2095
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the fact that the film is out of date isn`t that much of a problem either unless it Grossly out of date.
if it`s been stored well it will still work, it just may be a little grainy.
I have out of date film here and it works perfectly well, and you really wouldn`t be able to tell it was out of date ![;)](./images/smilies/wink.gif)
I also keep my used developer stop bath and fixer soln as well as film that didn`t turn out very good, it`s my plan to reclaim the silver from these
also.
but not because I Need the silver, but just to see if I can do it.
you can probably pick up an old polaroid cam from a second hand shop or garage sale for pocket change, I would at least Try to see if any of it works.
the only Real problem I can see is the built in flat-pack battery may not be much good.
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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not_important
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Given that Polaroid is dropping production of their film, you might make more money off it by finding cheap cold storage, tucking the film away there
in gas tight containers, and auctioning it off in awhile.
Quote: | Current film supplies are expected to last another year, but collectors and enthusiasts have already started stocking up on Polaroid memorabilia.
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http://www.dailyrecord.co.uk/comment/columnists/showbiz-tv-c...
Quote: | Conlogue uses Polaroid film when he travels deep into the Peruvian jungle to take X-ray photographs of ancient mummies so he doesn't have to lug
cumbersome developing chemicals. Now he and other enthusiasts who use the film for art or specialized industrial photography are left wondering where
they'll go to stay stocked.
"We're incredibly despondent," said Conlogue, co-director of the Bioanthropology Research Institute at Quinnipiac University in Hamden, Conn., where
researchers frequently visit remote sites to capture X-ray images of mummies. "I don't really feel that there is going to be a replacement for it,
which is a real problem." |
http://ap.google.com/article/ALeqM5iIJWhuHzGbzaZRhKjeuRpCtQv...
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Panache
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The problem is the film is polaroid 667, which is a medium format b&w stock used for polaroid backs on professional cameras such as hassleblad's
etc (or however it's spelt). So that makes me using it for fun and interesting happy snaps kinda expensive as i would first need the camera.
The film is dated to expire 8/05, it was cool stored in the uni basement so maybe i'll just gas bag it, seal it in a box and throw it in the back of
the coolroom for a few years.
My desire to extract the silver from it wasn't based in lack of funds or ability to obtain silver it was just he desire to do it.
Finally..........
Given this thread had now partially become a forum regarding speculating about my sanity, (i won't bother throwing the quotes in), i feel i must
defend myself to some extent.
The entire reason i placed the line about UTFSE in the starting post of this thread was because although i had spent some 60mins using the search
engine to find a suitable answer to this question i had not found one..........So........instead of saying 'yes i did use the search engine first' to
stop people from writing UTFSE several times in reply posts, i made up a little funny story to indicate this to people in another way.
And what happens.....people here stereotype me as being off topic, smoking crap blah blah blah and its all really fucking offensive (not really the
off topic stuff because there has been an element of that in other posts of mine but being told off like a child for it is rather offensive).
Making conclusions about someone and stating them in a public forum because they behave differently to how you would without any supporting evidence
whatsoever is just plain ignorant and bigoted.
In fact evidence of my behaviour contrary to this is there before you, if you bothered to look. Check my posting times, they are all within working
hours here in Australia, because i generally only log on to this forum while distilling (i'm a distiller in a real distillery, and no that doesn't
make me an alcoholic, i'm, a professional person with a degree or two working in an industry i love).
But no you'd rather draw conclusions that are not there, so scientific of you.
So either please apologise or refute with an argument that has a basis is something other than your pre-draw, unsubstantiated, ridiculous ideology
that people contributing to this forum must be smoking something if their expressive style differs markedly from yours', you dogmatic fool.
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MagicJigPipe
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I often wonder if it would be worth it to buy as much silver as I can now, and sell it later. As far as reclaiming silver from old polaroids... I
think the pictures are worth more than the silver they contain. So, I would sell the pictures and buy silver with the money, that way I would have
more silver.
Panache, I think some people were just being "playful" and were only joking. I mean, when I read your post I had to call my girlfriend to come look
at it and see if it made sense to her. Needless to say, we were both baffled and left wondering, "what the hell is this gibberish". We didn't think
you were "smoking" anything. We just figured we missed something or you were just strange.
Just calm down and let's continue this discussion, eh?
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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Panache
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well now that i re-read my original post i realise i missed a very important word, namely 'UTFSE', so where you see that now in the post is were it
was missing from previously. And i realise that I'm not insane it's just i had annotated 'UTFSE' with the pointy bracket things which means whatever
contained within those brackets disappears, such that the expression 'google' had also disappeared.
My joke actually makes sense now and everyone should go back and read it cos its funny shit eh.
And i'm very calm, always.
[Edited on 22-2-2008 by Panache]
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microcosmicus
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When I just now used the search engine I didn't come across any dimensional portals
but I did come across found a whole bunch of websites which sell the stuff:
http://www.bhphotovideo.com/c/product/42758-USA/Polaroid_636...
http://search.ebay.com/polaroid-667_W0QQcrlpZ991006253Q5f940...
http://www.adorama.com/PD667S.html
According to their description, the use of this film is
Quote: |
667 Film is designed for use in electrophoresis, photomicrography, photomacrography, oscillography, computed tomography, ultrasonography, and nuclear
medicine. 667 is also used in preparation of real estate ads and for instant documentation in law enforcement, insurance, building construction, and
architectural design.
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which would make sense given the provenance of your film. Given that the usual price is
around a dollar a sheet, so if you could find a buyer, at the going market rates you could
purchase more of any precious metal than you could reclaim from the emulsion. Given that
the stuff is going out of production as not_important pointed out and that there are bound to
be a lot of people out there who still have and use the equipment for which this film was
designed, it looks like you should be able to sell it.
Also, does your haul of lab gear happen to include any oscilloscopes or other machines as mentioned
in the description of the film? If so, you might be able to put the film to its original use.
As for the remarks about the remarks at the end, I was worried that you were incinerating
the film by smoking it in your pipe and that the toxic fumes were causing brain damage ![;)](./images/smilies/wink.gif)
[Edited on 22-2-2008 by microcosmicus]
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Panache
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thanks micro,
that info was useful. Most of the large equipment from the uni i ran out of time to remove as i only had a 4 day window and the stuff had to come down
three flights of stairs, across two buildings, then wait for pause in the demo guys throwing stuff out from the 4th floor window, across a carpark
and onto the truck.
I still wake up at night thinking about stuff i had to decide to leave behind. It felt like Vietnam all over again and i could only carry one bloodied
mate.
There was an awesome biological sample chest freezer that was brand new, about 8 foot long by 2-2.5 wide and stood about waist height. It simply
weighed to much i couldn't for the life of me get it out.
I still dream about it.
Anyway if i can find a buyer for the film i'll probably blow the money on food and wine.
As for the rant, apologies, just call me over-sensitive, i had been up for several days smoking opiates but injecting meth-amphetamine to counter the
depressive effects on my central nervous system, so maybe i over-reacted. Hey it's 2008, when did that happen?
I did open one twin pack (ie 20 sheets) trying to fit it into my 600 series polaroid so i'll try and re-cycle the silver from that for an excercise
just to prove my inorganic incompetence. I'll post here with photo's.
Sry for being off topic a little during the post
8)
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YT2095
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2005 isn`t all that badly out of date, I think you`ll find it will still work for the most part ![;)](./images/smilies/wink.gif)
and assuming you don`t have Massive amounts of Radon in your basement.
I for one would certainly give it a go with a least one picked at random, and see what sort of result I got.
as for silver I get mine from a jewelers and for Free, I just go in an ask if they have any scrap silver they don`t need as I want it for Photography,
most places are often happy to give you a good few ounces of broken silver stuff and split links and the likes.
one place even gave me a 1mm thick by 12x15cm plate of sterling silver!
it`s worth asking, the worst they can say is No
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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Panache
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Overnight i thought before i fired the crap out of my 20 sheets of opened film in the furnance i might as well try to be more elegant and extract them
with strong ammonia solution. My CRC tells me many silver salts are soluble in ammonia and a small pinch of AgCl dissolved readily in 5mL of 10% so i
have cut the sheets into strips and they are extracting happily in a soxhlet presently (after moving them from the lab bench to the fume cupboard lol)
So a quick question, i diluted my ammonia down to 10% for the extraction but what typically will the concentration of ammonia condensing on my
condenser (internally coiled) that drips down and does the extracting?
I'll let the baby run all day today and asses tomorrow. I am right to cover this stuff from UV/vis light correct?
Third question, given that UV light oxidises many silver salts back to the metal, but this i imagine would only occur negligibly because the silver
metal formed would readily absorb/reflect further UV/vis light, would a solution, well stirred, of say AgCl in aqueous NH3 ppt silver metal when
exposed to UV over time, would the reaction go to completion because of the ppt of the silver metal would continually drive the reaction to the right?
Shall i just try?
Finally does anyone have any oldy worldy recipes for silver wasser, apparently it's a colloidal silver alcoholic solution/suspension, not unlike gold
wasser is that gold leaf in water. I'm thinking it would make for an interesting new alcoholic beverage.
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a_bab
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The furnance is the only reliable method for silver extraction from films, as it used to be the commercial one. Unless you'd like to scrape off the
gelatin from the strips...
Also, since these filmes were used, a part of the silver (likely most of it) went into the fixer, so no more 0.25 grams/filmstrip.
As about the "silver wasser", you may get this out of it: http://images.google.com/images?&q=argyria
Check the wiki for argyria, there are quite some interesting stories about it. Not that you've got enough silver in your filmstrips/polaroids/whatever
to get the disease due to the exposure... But colloidal silver for drinking is a different story.
And BTW, there is colloidal gold aswell. It's red, and it's used for ceramics (pottery) to get the gold color.
[Edited on 27-2-2008 by a_bab]
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Panache
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well the ammonia/soxhlet extraction sucked, burn the remainder will I.
In relation to silverwasser, i was not not intentioning an ionic silver solution rather a suspension of the metal. I have been able so far to grow
kind of a dendritic web like maze within a bottle (which would in theory then be rinsed and filled with your 'silver booze', which itself would be
silver free, except so far replacing the booze destroys the beautiful fine geometry). But i'm sure this shit that's been done somewhere by someone.
I'll post the photo's of the polaroid mess as soon as i find the cable for the camera (moving sucks)
btw those blue people were creepy. /shudder
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quicksilver
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In regards to the cost of materials and growth in their price and availability, it seems that such a thing as pulling expensive materials from
inexpensive sources is a damn good idea.
A company I worked for a time back had an account with Spectrum Chemical and they has "specials". I had a chance to buy up some silver nitrate (at a
fairly low cost at the time) and did so.... Jesus Harold Christ, that stuff went through the roof in terms of cost. A single bottle of 500grs is
selling for about $400!!!! I have well over a couple thousand dollars worth of silver nitrate. I would be damn interested in continuing this agenda.
- My point here is that it seems one can speculate on chemicals in a manner similar to speculating on the Commodity Market. If such a thing can happen
within that example; could it not happen with others (& virtually all the time?).
Certain materials are used more in certain times. In a period of rapid arms production aren't various metals (platinum) used in missile development?
We can see various opportunities all around if we can predict what market will expand. Right now we have a period of arms development and procurement
and possibly a switch to alternative energy formats. If the correct predictions are made, someone will be making a bit of money. ....Happens all the
time. If silver grew that much, what else would grow at such a rate?
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a_bab
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This is an interesting point, that fascinated me aswell.
The price of gold has constantly increased, and frankly I see no possibility for it to drop in the near future. It doubled in the past 3 years I
guess.
The mercury on the other hand, as the need for it decreased due to the tendency to eliminate it (enviromental issues) went down from 60 dollars to 30
dollars as today. There are many other interesting prices; I attached a document with the prices for metals over the last century.
Attachment: Metal Prices in the United States through 1998.pdf (884kB) This file has been downloaded 988 times
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Aqua_Fortis_100%
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Today I extracted my silver , from X rays films, from several hospitals. I'm now washing the Ag powder and will see how much was extracted..
The procedure for extracting silver from these is VERY simple and not require any complicated technique, like burning sheets or such.
Quote: | The furnance is the only reliable method for silver extraction from films, as it used to be the commercial one. Unless you'd like to scrape off the
gelatin from the strips... |
The only chems required to extract silver from X rays and another films are : bleach , NaOH and commom sugar .. not more than this.. The Ag powder
obtained is relatively pure for chem experiments, but if you like, you can reffine it , using a torch and borax (or boric acid), and the result are
small balls of silver metal..
You only need to put the negatives/X rays films in bleach for some minutes.. The gelatine (containing silver powder) on the surface of the film will
dissolve very fast (do it outside.. bad smell) .. Initially, the powder is black, but will turn white, as the hipochlorite oxidise the Ag to AgCl and
a small amount of Ag2O..
4 Ag + 2 ClO- + H2O ---> 2 AgCl + Ag2O + 2 OH-
then, after all gelatine removed from the films, you can wash the plastic base, to remove residual silver compounds, which are removed and added to
bleach leaching solution..
Then you need to decante the solution, at least for one day (some of the ppt are very very fine) ; the white mud resting in the bottom, you can
separate and put in a pan (preferably a disposable pan... I've used enameled pan, which was fine to work) ; then you can add some water , NaOH and
sugar (in aprox. 1:2 vol. ratio (the procedure where I see this use teaspoons to make the method more "otc" possible))...
Then , boil for approx. 30 mins.. The solution quickly turn brown then black , since the silver compounds are reduced to silver..
Then you can neutralise the solution with an inorganic acid (organic acids will form and give a bad smell.. do this outside) and filtrate it with a
commom filter paper.. Most of the silver particles are easily filtrated.. then washed on filter...
Done!
If you wish to reffine the silver, you can melt borax (Na2B4O7.10H2O) and put on a porous refractory ceramic where the silver will be melted (first
the molten borax is put on the ceramic, to fill the pores and avoid the silver getting inside it).. Then Ag powder.. The boric oxide and NaBO2 (Na
meta borate?) are formed and effectively remove copper and another impurities.. The molten silver , then is dripped in a container with water, to form
small granules..
Boric acid can be used instead, or then some mixtures, like borax, Na2CO3 and NaNO3 as flux..
I dont tried reffining it, as I dont have any sort of torch lying around..
A similair procedure can be found in US 3,960,550 ("silver recovery process"), attached, but their procedure for reffining the silver is somewhat
different and dont give a very pure silver, and thus need to be repeated one or more times..
[Edited on 11-4-2008 by Aqua_Fortis_100%]
Attachment: US3960550- silver recovery.pdf (304kB) This file has been downloaded 634 times
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Contrabasso
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Silver recovery from plain fix is low current electrolytic, from bleach-fix it is high current density electrolytic.
To get silver from film and papers fix or Blix them then recover from the blix.
Furnace methods produce too much fume for the small amount of silver recovered.
The simplest method is to get a large bucket full of steel wool and very slowly pour the silver bearing solution through - like days! The available
iron replaces the silver in the solution and a sludgy mass of silver loaded steel wool will develop. Use silver indicator papers and when noticeable
silver shows on the paper, change the cartridge! a commercial cartridge about 4 gallons used to be on the market and weighed about 20 lbs dry later if
fully used to recover silver 22kilos of fine silver was recoverable by the refiner. and payable!!!
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crazyboy
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Quote: | Originally posted by Aqua_Fortis_100%
Today I extracted my silver , from X rays films, from several hospitals. I'm now washing the Ag powder and will see how much was extracted..
The procedure for extracting silver from these is VERY simple and not require any complicated technique, like burning sheets or such.
Quote: | The furnance is the only reliable method for silver extraction from films, as it used to be the commercial one. Unless you'd like to scrape off the
gelatin from the strips... |
The only chems required to extract silver from X rays and another films are : bleach , NaOH and commom sugar .. not more than this.. The Ag powder
obtained is relatively pure for chem experiments, but if you like, you can reffine it , using a torch and borax (or boric acid), and the result are
small balls of silver metal..
You only need to put the negatives/X rays films in bleach for some minutes.. The gelatine (containing silver powder) on the surface of the film will
dissolve very fast (do it outside.. bad smell) .. Initially, the powder is black, but will turn white, as the hipochlorite oxidise the Ag to AgCl and
a small amount of Ag2O..
4 Ag + 2 ClO- + H2O ---> 2 AgCl + Ag2O + 2 OH-
then, after all gelatine removed from the films, you can wash the plastic base, to remove residual silver compounds, which are removed and added to
bleach leaching solution..
Then you need to decante the solution, at least for one day (some of the ppt are very very fine) ; the white mud resting in the bottom, you can
separate and put in a pan (preferably a disposable pan... I've used enameled pan, which was fine to work) ; then you can add some water , NaOH and
sugar (in aprox. 1:2 vol. ratio (the procedure where I see this use teaspoons to make the method more "otc" possible))...
Then , boil for approx. 30 mins.. The solution quickly turn brown then black , since the silver compounds are reduced to silver..
Then you can neutralise the solution with an inorganic acid (organic acids will form and give a bad smell.. do this outside) and filtrate it with a
commom filter paper.. Most of the silver particles are easily filtrated.. then washed on filter...
Done!
If you wish to reffine the silver, you can melt borax (Na2B4O7.10H2O) and put on a porous refractory ceramic where the silver will be melted (first
the molten borax is put on the ceramic, to fill the pores and avoid the silver getting inside it).. Then Ag powder.. The boric oxide and NaBO2 (Na
meta borate?) are formed and effectively remove copper and another impurities.. The molten silver , then is dripped in a container with water, to form
small granules..
Boric acid can be used instead, or then some mixtures, like borax, Na2CO3 and NaNO3 as flux..
I dont tried reffining it, as I dont have any sort of torch lying around..
A similair procedure can be found in US 3,960,550 ("silver recovery process"), attached, but their procedure for reffining the silver is somewhat
different and dont give a very pure silver, and thus need to be repeated one or more times..
[Edited on 11-4-2008 by Aqua_Fortis_100%] |
My friend and I attempted this procedure yesterday and the results were less the spectacular, we had about 25 large X-ray films. They were soaked in
bleach and after a while with scrubbing the color gradually came off leaving us with a clear blue sheet and murky gray solution. We decanted and were
left with a silvery gray powder suspended in water.
I now believe THIS was the silver but we decided to follow your directions and boil with sodium hydroxide and sugar. The mix turned brown but not
black we neutralized and were left with lots of clumps. We filtered and were left with a dirty brown mash with lots of clumps. When heated at very
high heat for long periods of time tiny silver globules formed on the brown organic crap. I now believe that I should have filtered they gray solution
and kept it as it seems much more likely that it is silver.
Also what was the sugar for!??!!?
[Edited on 11-5-2008 by crazyboy]
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12AX7
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The silver comes out as halide or oxide and needs to be reduced to get metal.
Tim
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crazyboy
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Well in his procedure he said the particles came off as a white sludge mine came of as a grayish muck so something is different.
It is possible that it is not silver but a silver oxide or something but if this is the case how would I reduce it to silver?
I don't doubt you as your metallurgy pager is quite impressive it's just when I followed his instructions the results weren't the same. I think I will
repeat this but I will melt the gray sludge in a crucible I just made.
I will take pictures and notes so if all goes well I can post a complete write-up and if not maybe someone can point out what I did wrong.
[Edited on 11-5-2008 by crazyboy]
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woelen
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The grey material is impure silver chloride, the impurity being silver oxide.
I probably would have filtered the grey material and then have heated this with a solution of NaOH and glucose. The sugar is needed for reduction of
the silver chloride/oxide to metallic silver. Normal sugar is not that good a reductor. A better reductor is glucose.
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Panache
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I had dark, crumbly revolting cake of several past attempts at recovering silver (including using iron, zinc, copper, ammonia, bisulphite), as trials
didn't turn they went into the same 5l beaker (including filter paper, teflon wool etc). Eventually i poured the contents of the beaker into a baking
dish and dried it off.
As one can imagine, it was without enthusiasm or suspense i broke off a piece of my crazy cake, ground it up, and mixed it through a freshly prepared
thiosulphate solution (200g/L).
The solution stirred on a magnetic stirrer at RT for 1hr and was gravity filtered through fluted filter paper.
Glucose syrup (150g) (from the baking aisle at the supermarket so actual glucose content not known but was very thick!!), sodium hydroxide (50g) and
water (500mL) were added to a beaker in that order. The sodium hydroxide got 'stuck onto the glucose syrup and caramilsed the sugar in localised
area's before i could adequately disperse it through the water. I tossed that and repeated the combination this time dissolving the hydroxide in
water firstly then the glucose syrup. The resultant solution was a semi bright yellow colour. Into this warmish mix was poured the thiosulphate/crap
cake. The solution immediately went brown then grey with ppt and after 5 mins of stirring agglomerated silver crap had accumulated at the bottom of
the beaker. The solution was again gravity filtered through fluted filter paper, the silver crap washed thrice with D-h2o and low and behold it
appeared to be powdered silver.
I placed this apparent silver powder without weighing it (about 2-5g??) into a 50 mL conical and added a few pipettes of ~35% nitric acid. The powder
reacted shortly thereafter and brown plumes of gas came off the vigorous reaction. Upon completion the solution was bright yellow with a small
suspension of a bright yellow ppt.
The ppt was filtered out and treated with ~20ml of the thiosulphate solution. the ppt dissolved and further treatment with the gluicose/NaOH produced
more fine grey powder.
The remaining yellow solution was evaporated to dryness, during which the colour changed from yellow to green to light green to bright green. Finally
silver nitrate crystallised out from the boiling green solution. I knew it was silver nitrate as i recognised the crystal structure and distinctive
mauve hue apparent still despite the green.
The remainder of the cake was thus extracted and the silver nitrate washed thrice thoroughly in 99.5% ethanol, this served as sufficient to clean the
crystals up nicely.
Ok now i need something to do with this 1.1kg of silver nitrate, i was thinking of making up a mirror solution in the bathtub and jumping into it!!
Or maybe i will smear silver nitrate solution's randomly on handrails about the place for the next 5 years. Given how many times i have stained my own
hands it seems Ok for other people to have the same fun.
So FTW use glucose!!!! and as a bonus your lab will smell like a caramel factory for a short while.
Thanks to crazyboy for the reference.
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