# What’s the reason?



## Jmk88 (Jun 16, 2020)

Why do people adopt the sugar and lye method as opposed to what Hoke teaches? 

I have tried this three times and I have never been successful. 

What is the benefit of this over Hokes method? 

Kindest Regards


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## goldenchild (Jun 16, 2020)

Speed and high purity is why I use that method. I am able to remove the silver from copper without having any copper contamination using salt or HCL. Then form elemental silver from the chloride. My silver is consistently 4 nines using the method. What part of the process are you unsuccessful with?


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## Jmk88 (Jun 17, 2020)

The silver never converts. Although someone has pointed out I am not using enough lye.

I am gonna to proceed with Hokes method today using aluminium shavings rather than zinc.

Following her word religiously has worked well for me so not gonna change that!


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## butcher (Jun 17, 2020)

Lye sugar method does not work very well if the silver chloride is not fairly pure...

Converting the silver to metal by displacing the chloride with a metal like iron (dilute H2SO4) or zinc or aluminum (HCl) will work better with dirty silver chloride that has other base metals involved...

I personally I prefer iron and dilute sulfuric acid over the other methods...


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## goldenchild (Jun 17, 2020)

Before you give up on this method... I suspect you may not be creating enough heat. Heat is key using this method. It not only does the actual conversion but mixes things around to touch any chloride that wasn't fully converted to oxide. When you have your nice clean chloride separated from everything else try this. Put the beaker with the water and chloride on a hotplate. Let it warm a bit. Then add your hydroxide. Then the sugar. 

I don't know how much silver you are trying to convert at one time but it may be that if only trying a small amount the hydroxide added to the water might not get everything hot enough. The sugar will get things even hotter but again if there isn't alot of material to convert it will not get enough heat. This is why when processing moderate to large amounts heat is easily generated to complete the process. Here is my video that I've posted a million other times. Is this how you basically go about it?


Note you can clearly see I didn't fully convert the chloride with the hydroxide additions. That's where the heat from the sugar comes in (boiling).
https://www.youtube.com/watch?v=xM-YsiFnJ1I


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## butcher (Jun 17, 2020)

goldenchild,
I enjoyed watching your well-made video with my morning coffee this morning.
Thanks


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## goldenchild (Jun 23, 2020)

butcher said:


> goldenchild,
> I enjoyed watching your well-made video with my morning coffee this morning.
> Thanks


Thanks 8)


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## glorycloud (Jun 23, 2020)

Very nice! I enjoyed the video!


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## nickton (Aug 19, 2020)

I am also currently trying to use the sugar/lye method a la Sreetips' YouTube video on processing Xray films, and am not succeeding yet. 

https://youtu.be/0tn-a0S0FD8.

I'm not sure exactly what's going on or how to describe it but it appears I have trouble washing it properly, and getting separation from the silver and whatever else I don't want, which I imagine to be spent bleach mixed with fixer chemicals (thiosulfate?).

I think the use of hot water is important in the washing process, but I still notice too much grey liquid rinsing out when I do it the way Sreetips did, so I tried slowly evaporating the rinse rather than discarding it (if that makes any sense), and it seems to be working better. The light grey liquid boils down to a dark sludge that must be part silver:





I also boiled some after adding enough lye to make it blackish, and then adding sugar (
too much probably). And here is where there appeared to be little separation to provide for proper rinsing:






Okay. I did do some of this "bass ackwards" so far so it probably doesn't make much sense. The solution in the Crystal Geyser water bottle is actually material I originally processed with lye and sugar, but without HOT water. It would not separate at all and was a solidly brown and blackish solution, that I decided to simply evaporate down to a dry mud and attempt to melt into silver shot with no success, so I added water again to get what is now evident in the plastic jug.

The other beaker contains the bottom sludge from some sugar and lye added material that I boiled for a while. I think this is the closest to the so called "pure" silver I want to ultimately get so far, but I wouldn't be surprised if it did not melt cooperatively into anything, and am sure it needs washing, but I am afraid to to that because I don't want to lose silver in the wash, and am not sure separation will occur. 

This is about where I'm at. I think evaporating down the wash is a good idea, and may help to further neutralize any bleach residue and create better separation between silver halides and diluted bleach or fixer residues. I read somewhere that bleach boiled down turns into harmless salts, but this is admittedly vague. I am wondering whether the slightly whitish material mixed with grey liquids is silver chloride or just bleach. Here is a picture of the material without anything done to it:







I think I managed to successfully convert the silver, but cannot seem to separate it from undesirables yet.


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## goldenchild (Aug 20, 2020)

Here's a tip that you and others can use. One of the most important parts is rinsing the chloride clean after dropping it with salt or HCL. It should be snow white when fully cleaned. Although it helps it's not necessary to use how water for washings. 

The key is very good agitation when rinsing. When doing big batches I'll put the chloride in a 5 gallon bucket. Then hit it with the garden hose using the shower setting. With the relatively high pressure it breaks up all the chloride and lets the water get into all the cracks and crevices. So use a vessel that gives plenty of room for the chloride to move around and a high pressure water source. If you're gonna pour water like sreetips you have to really stir and agitate the chloride after the water is added.


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## geedigity (Aug 20, 2020)

A couple things that can also be considered:
1) I usually do not have to add heat, since plenty of heat is generated with the addition of dry NaOH (I add excess) to the silver chloride and water. Thorough mixing is the key to a complete conversion. I heard that adding to much NaOH can create a soluble silver compound, but it has not seemed to be a problem for me. 
2) I never have had any success with cane sugar;
3) Karo corn syrup or pancake syrup seem to work well;
4) There is a point after rinsing the silver chloride where the silver chloride will not settle quickly. The cloudy rinse water can be poured into a bucket where it can slowly settle and be recovered later;
5) I verify my silver chloride is clean by taking a small sample of the rinsed silver chloride to which I add sodium carbonate. If I see blue tint appear, I rinse again with vigorous stirring to break up any clumps of silver chloride. The blue would seem to indicate that more copper needs to be rinsed out.
6) After converting the silver chloride to silver, when rinsing the silver, there is a point where the silver begins to cloud the rinse water and it will not settle quickly. Pour the cloudy rinse water into another container and let it settle over time. 
7) The downside of the lye/sugar method (and a few other methods) is the volume of relatively dilute copper containing rinse water. Add a little HCL and iron scrap, and the copper cements out pretty completely over the course of a couple days.


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## nickton (Aug 21, 2020)

my computer is messing up. I just lost this post. I am not converting from chloride I don't think, and am processing about 200lbs of X-ray film.


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## nickton (Aug 21, 2020)

The difference between my situation and the usual conversion from silver chloride is that my material comes from bleached X-ray film stock, so cleaning it will not result in that purely white cottage cheese like material. I get a gray substance that doesn't seem to drop down into a separated solid very well when hot water is added. 

However I do notice that evaporation concentrates the material pretty well and I can add hot water to that to get a brownish wash that is separate from the solids. It is rather different from the Sreetips video, which makes it look easier, and the evaporation seems to be a key step for me. 

Unfortunately I jumped the gun with adding lye and sugar, so I am now stuck with most of my first batch locked into a seemingly un cleanable soup. I may however get some settling if I wait longer.

I might try adding HCL , or sulfuric acid to see what happens. Perhaps I can get back to making some silver chloride that way.


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## nickton (Aug 28, 2020)

Good news: Today I checked the lye/sugar mixture and noticed a line at the bottom that separated grayish solids from brownish wash water, so the process appears to be working after all, just a lot slower than I first thought it would. 

I will continue then with hot water washes and then see if I can melt down some silver.


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## nickton (Sep 7, 2020)

Since I'm at it I will post some more results here. I finally got my first silver from processing some but not all of my first batch, and got 11 grams of pretty pure looking material:

My problem now seems to be an insufficiently hot enough flame coming from my propane Venturi set up. It sure sounds good--it just takes too long. I had a cylinder of Mapp gas before that ran out and seemed to take less time to melt down silver.
But I finally got some decent results after using a new smaller crucible. My other ones became very dirty. Must have been a lot of impurities despite extensive washes.

Here are some pictures:


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## Palladium (Sep 7, 2020)

The silver coming off that film should already be pure. No reason to convert.
Collect the powder and at most give it a hcl wash followed by water and melt.


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## nickton (Sep 16, 2020)

Hmm. Maybe I'll try that then. So no need for the painstaking rinses with hot water? Just pour some Hcl onto the black and grey stuff?

It seems I should at least do the initial rinses.


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## rickbb (Sep 16, 2020)

If your source is just old x-ray film you already have 99.7% pure silver, or better. 

The bleach dissolves the gelatin that holds the silver grains to the plastic film and lets silver settle in the bottom of the bucket.

After it settles, siphon off the liquid, then rinse with water, let settle, siphon, repeat this many times. Repeat until the "mud" is very black and the rinse water is mostly clear and the mud will rinse and settle quickly. 

When rinsed well, filter, let dry and melt. No need for any conversion as you already have metallic silver to start with. 

I've never washed silver from x-ray film with HCL. And as stated you would only need to do that if you had metal contaminates from something else.


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## nickton (Sep 18, 2020)

Okay then. I wil try that with the next batch for sure.

Thanks.


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## ION 47 (Sep 20, 2020)

Hello! I also work with X-ray films. I used several methods: the method of bleaching-fixing and electrolysis, the method of bleaching in ferric chloride solution with washing with hyposulfite and electrolysis. these two methods do not allow to remove from the film some of the silver sulphide that is present in the emulsion. Because of this, I had a 10% loss. I tried the chlorine bleach method, but the large amount of water required to rinse the film stopped me. I process about 1,000 pounds of film a day. Now I am choosing filtering equipment for silver chloride, and I also want to use a chlorine generator, so as not to buy hypochlorite, but to prepare it myself from salt by electrolysis. I think that if I can solve these two problems, then the chlorine bleach method will be profitable for my volumes.


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## rickbb (Sep 21, 2020)

The most efficient and cost effective process of recovery of silver from old rare earth x-ray film has been well know for over a half century. Several old patents on variations of the method from the 1920's and 30's exist, so almost a 100 years old.

Using the tried and true process of 20% to 30% sodium hydroxide with about 5% sodium hypochlorite, (by weight), heated to about 180o F, (just under boiling), with gentle agitation you should get about 1ozt silver per 10 pounds of rare earth x-ray film.

Occasional replenishment of the bleach is required as the destruction of the emulsion converts the bleach into plain sodium hydroxide over time. Still works without the bleach, just a bit slower.

Large scale, commercial silver recovery companies use this method. Or used to when people still used that old film. Everyone has gone digital nowadays, so you getting 1,000 pounds per day is quite a feat.


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## ION 47 (Sep 24, 2020)

rickbb said:


> The most efficient and cost effective process of recovery of silver from old rare earth x-ray film has been well know for over a half century. Several old patents on variations of the method from the 1920's and 30's exist, so almost a 100 years old.
> 
> Using the tried and true process of 20% to 30% sodium hydroxide with about 5% sodium hypochlorite, (by weight), heated to about 180o F, (just under boiling), with gentle agitation you should get about 1ozt silver per 10 pounds of rare earth x-ray film.
> 
> ...



Yes, almost the whole world has switched to digital X-ray diagnostics. In Russia, 70% of X-rays are still working on "wet" film. I collect about 20 tons of film per year from a region of about 5 million people. These are mainly medical films, and some diagnostics of metal welding. My equipment allows you to process 1000 pounds (even more, 800 kilograms) in 24 hours, I get 2 kilograms of silver per day .. But for the last few years I have not included this process every day.


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## nickton (Oct 2, 2020)

Great information. I will surely try the tried and true method with some of my 300 lbs of Xrays I got for free on Craigslist. It certainly sounds like a lot less hypochlorite is used up that way. I've consumed 5 gallons of bleach for maybe 20 lbs. of material (at most). 

It also doesn't surprise me that other countries still rely more heavily on older technology. My Xrays came from a contractor who remodeled a Veterinary clinic in Marin county, California. i'm sure they'll go digital now, and I don't expect to come across any more again. It was nice to learn the process too. A lot easier than gold refining IMHO.


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## rickbb (Oct 7, 2020)

You can also sell the film as is, last batch I sold, (couple of years ago), went for $1 a pound.


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