X-Ray film yield

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eaglewings35

Well-known member
Joined
May 27, 2010
Messages
205
Okay here it is.....
Almost 1year ago I bought 200lbs of green industrial X-Ray film. I began by buying
Some sodium thiosulfate (fixer without a hardener) I would sit for hours next to a 5 gallon bucket with 2:1 fixer and water. I later upgraded to 3 buckets. I would put in 1 piece at a time in each bucket, as it cleared I would add more film. Once the film got to about 6 inches think I would fish the blue plastic film out and move it to a rinse water bucket.
Once the fixer was saturated (took 5 minutes to clear the film) I added 1/2 gallon of HCl to convert it to silver chloride. Once it all settled I drained off the acid and transferred the AGCl to some 1 gallon glass jars. I then added more HCl and some iron nails.
Once it was all converted I siphoned off the acid, poured the grey concrete colored silver into a bucket again. Now I would take 3 boiling pots of water and pour onto the top, and stir thoroughly. Once it settled I would siphon off the water and repeat with more boiling water rinses. It would take about 4 or 5 times but it would get to where it settled quickly. Now I would siphon off the water and then I would add 1 gallon of HCl to eat up any remaining iron. I would let it sit 2 or 3 day stirring often. Then I would siphon off the acid and repeat the boiling water rinses until it settled quickly.
Then I would dry it.
So out of 200lbs of green industrial X-Ray film the yield for me was 204 troy oz.

Thanks for reading
Kerry
 
Certainly Sir.
Ive seen many questions asking what the yields are for different types of film, so I felt that I should share this info with the forum members.
I was personally surprised at the yield. I didnt know it would be any where near that amount.
But the results dont lie !!!
I mailing off 114 troy o tomorrow to a forum member (there are several letters on my laptop that have quit working, and one of them is the last letter of the alphabet)
For information purposes.... 114 troy o weighs 7.85 lbs.
 
If you mentioned melting, I didn't find it. Did you melt it or did you just dry it? If you just dried it, I would question your yield.

Your yield of 1.02 tr oz/pound is higher than any virgin industrial x-ray film I've ever seen. The 100s of assays I ran on this film always came in at about .65 tr oz/pound, if I remember right. I'm not saying you're wrong. Different brands can yield differently. Maybe yours was some sort of special film.
 
goldsilverpro said:
If you mentioned melting, I didn't find it. Did you melt it or did you just dry it? If you just dried it, I would question your yield.

Your yield of 1.02 tr oz/pound is higher than any virgin industrial x-ray film I've ever seen. The 100s of assays I ran on this film always came in at about .65 tr oz/pound, if I remember right. I'm not saying you're wrong. Different brands yield differently. Maybe yours was some sort of special film.
Chris, you are correct. I put the dry weight, not the refined weight.
The man whom im sending this to will do the final process of refining.
My apologies for the mis-statement. In my zeal to finish I totally skipped the "refined weight"
As for the film.... this came from a company (NDT) that uses this film in x-raying pipes being used in the oil
field. It was pretty thick, about 60 pounds would totally saturate my fixer solution.
I will ask the member that is refining it to let me know the final yield after he finishes refining it.
Then I will update this post.
 
Is sodium thiosulfate the only chemical that can be used to remove the silver from the film? Or is there something else that works better? Thanks!

kadriver
 
kadriver said:
Is sodium thiosulfate the only chemical that can be used to remove the silver from the film? Or is there something else that works better? Thanks!

kadriver
If you're asking what chemicals will dissolve the silver halides (AgBr or AgCl) from undeveloped film, the only others I can think of besides the thiosulfate are cyanide or ammonia. Both halides readily dissolve in Na or K cyanide, but the AgCl in more soluble in ammonia than the AgBr. I'm thinking that AgBr is the primary silver halide on film. Hypo, sodium thiosulfate, is the safest, of course.

If you're asking just how to remove the black silver metal from the developed film, there are many things that will attack the gelatin emulsion that is holding the silver on the film, including NaOH, bleach, and steam. To actually dissolve the silver on developed film, nitric acid will work, although I've never used it in production. I've used nitric for literally thousands of film assays. The old pre-EPA standard for dissolving silver, whether as metal or a halide, was NaCN plus an oxidizer. The silver was then plated out and the cyanide re-used. Cyanide is still the #1 best way to process any type of film but, after some guy died in the '70s in a film processing plant in Chicago, and 60 minutes did an segment on it, no one that I know of still uses it.
 
Thanks GSP, I've got some developed film that I want to try and get the silver from for a new video. But I have zero experience. If I can get the silver off of the film as a chloride, then I know what to do after that. Can I soak it in bleach? Thanks again. Kevin.
 
You can use bleach, but it does not affect the silver, it dissolves the protein based emulsion that holds the silver salts to the polyester film. The silver then drops to the bottom where you collect it for further processing/refining.

The process of dissolving the emulsion will convert the bleach into plain lye. Depending on how much film you are recovering you will have to replenish the bleach. I've found that 1 gallon of 5% bleach in 3 gallons of water will strip about 7 lbs. of medical x-ray film before it slows down and needs more bleach.

If you go this route I'd suggest skipping the bleach and just use the lye method as that's what you end up with anyway, and it costs less than bleach.
 
rickbb my question to you is . I use the lye only process. I am getting alot of salts in my filters as my solution cool down. Do I have to much lye in my soultion ? or how to fix this problem .
Thanks
 
dscrapper said:
rickbb my question to you is . I use the lye only process. I am getting alot of salts in my filters as my solution cool down. Do I have to much lye in my soultion ? or how to fix this problem .
Thanks
How much weight of lye are you using per gallon of solution? Are you using lye or caustic soda or sodium hydroxide? They are all the same, chemically, but they vary as to their purity. Lye is the least pure of the 3.
 
goldsilverpro said:
dscrapper said:
rickbb my question to you is . I use the lye only process. I am getting alot of salts in my filters as my solution cool down. Do I have to much lye in my soultion ? or how to fix this problem .
Thanks
How much weight of lye are you using per gallon of solution? Are you using lye or caustic soda or sodium hydroxide? They are all the same, chemically, but they vary as to their purity. Lye is the least pure of the 3.
I use sodium hydroxide about two to three tablespoons in each 2 gal of water heat for 1-2 hours then filter solution . old xray are from the 60's & 70's .
I do reuse the soluion each time
 
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