Stock Pot Processing

[aga]

Having discarded any notion that i've got any kind of a clue at all, Processing the Stock Pot has begun , religiously following Hoke's instructions.

Firstly, the Zinc. All that is available is zinc ingots (kilos) and a very small quantity of zinc powder (a few 10s of grammes).

The ingots were drilled to produce twists/chips and this appears to work, as the solution eventually 'throws down' a precipitate and goes dark green, not light green or clear. The whole reaction was left overnight instead of 4 hours. This was tested on 1 litre of the stock pot contents rather than the whole 4 litres, just in case.

On filtering, the filtrate is a pale green, leaving a dark powdery substance in the filter paper. Filtering is not finished yet, as it goes through the filter paper quite slowly. I could rig up a Büchner vac filter, but am reluctant to try to save time in case i just screw it all up again.

A big worry is whether too much Zinc was added, or too little.

The sheer volume of what looks very much like Copper in the precipitate is also troubling.

Hopefully this all sounds 'normal' to experienced refiners.

If not, Please suggest what's already gone wrong.

Edit: corrected typo(s)
Edit: more typos

 

[Topher_osAUrus]

Thats the issue that I have with zinc, it throws down copper.
Which is cause for basically rerecovering what pm's are there.

I like doing the copper stockpot #1 then decanting it to waste pot#1, which is loaded with lots of iron. Leaving the sludge on the bottom of stockpot 1, and adding new waste solutions to it, to cement out on the copper. That way I dont have to remove lots of copper feom the precious metals again, yes there are traces, but not nearly the amount that you will deal with when using zinc to throw down.

And, lazersteve mentioned that if you use zinc on waste stream that has SO2 in it still feom gold precipitating, you could inadvertently create hydrogen sulfide gas and murder yourself... So, that doesn't sound fun to me

Zinc is nice and quick though. ...compared to the copper stockpot which can take days to cement, longer if no agitation is applied.

 

[Justincase]

I Have just emptied the sludge for my stock pot into a 10L beaker.
It is the acumination from about two years work.
I take a much more stately pace as to management.
It is a 60L drum with copper as a back fall, but most of the silver is deposited as chloride.
I fill it to the top and leave it at least a week before half emptying to make space for more liquor.
Then there are all the little bits of junk and left over's that where too small or dirty to work into my main stream of processing that I add each week.
You have to expect a lot of other metallic compounds as well basically any by product that has a low solubility in water.
Of a 10L beaker about one third looks like a nice gray sediment, it is on its fourth wash trying to remove the soluble compounds.
I will not put that in the tumbler until the wash water is looking fairly clean or all the metallic compounds will cement when the iron is added. This takes quite a while as you can only fill with clean water, agitate and let settle by it's self.
The Chloride's will still have enough base metals which will convert back to metals as it is.
But I do not see base metals as that much of a problem, we need collector metals in any case.
The noble metal content will be above coin silver which is still profitable to digest in acid.
I do not have a problem until I have finished A.R. digestion of the residual detritus left over from my initial nitric wash.
The last few times I have detected Rhodium but not having the ability to process my self and the amount being below a level of commercial interest I just put that back into my stock pot and save it an other two years.
May be by then I will know what to do with it.
A great place to store wealth, very few thief's would look at a drum of sludge and see value.

 

[Topher_osAUrus]

Justin, do you put your nitric digestion in that stock pot as well?

I have 2 stock pots, #1 for AR and #2 for nitric digestions of goldfilled, inquarts, silver (after cementing a couple days, it goes from my 3.5gal bucket to my 5 gallon "stock pot"#2).. Currently I have two of the #2 stockpots, as I kind of want to try to remove the copper by electrolytic means and reuse the nitric.

I just wondered when you said the majority of your silver is in chloride form. I have another 3.5gal bucket for storing my silver chloride from AR digestions.

I like the idea of just one main stockpot though, to keep it simple.
I just took hoke as bible truth, when she said to keep unused nitric from the stockpot... But, I would like to know more of your methodology.

 

[Justincase]

I did use to run a smaller stock pot just for my gold wash and spent liquor.
But I made the mistake of adding a solution with a little silver nitrate which mucked that up.
So as they both needed the same processing I have just been running the one stock pot for any thing that may have a little value. If My turnover improves I may return to a separate stock pot for my Ag liquor.
We do not have any sources of naturally occurring rich preciouses metal ore in Devon.
some Tin ,copper and tungsten mines that have a very low yield in comparison to some of the ore you have in the states.
So I look at my stock pot as the closest analogy of natural ore I have to look at.
Very interesting.
My first few runs where a lot of work for not a lot of metal which is why I leave it longer and let the quantity's build up.
If you have enough copper in your stock pot any acid will be used up if it gets that far.

 

[Topher_osAUrus]

I understand, and appreciate, that train of thought.

Do you reuse your copper powder thats displaced after treating with iron? I have just been saving mine up, but I think thats the route I am going to end up taking from here on out. Just to keep my expense on copper at a minimal level. The copper that has cemented out has all looked very clean, except for one stock pot batch that looked dark and terrible. So it went into a separate container.

My end goal with waste treatment is to become efficient to the point of it being self sustaining, with my only expense being NaOH and the HCl to adjust the pH. ...of course I will still have to source the iron, but, to call that an expense would be a gross exaggeration, since that is something that is free and very abundant (my father owns a fabrication/machine shop, father in law is a scrapper)

Edit to add:

I agree completely though, processing the slimes on a small and individual basis is kind of counter intuitive to the stock pot process as a whole. Afterall, if you are just processing a gallon of waste, and then redissolving those powders and going through the process, you in turn create that much waste again (or darn close, after washes, etc...) so, saving up the sludge for awhile and treating the barren liquid batch by batch is probably the best way to go about it.

But, I wouldn't mind being corrected on that. I'd like to know how others go about it as well.

Thanks Justin, aga, and anyone else who adds to this further

 

[Justincase]

I understand, and appreciate, that train of thought.

Do you reuse your copper powder thats displaced after treating with iron? I have just been saving mine up, but I think thats the route I am going to end up taking from here on out. Just to keep my expense on copper at a minimal level. The copper that has cemented out has all looked very clean, except for one stock pot batch that looked dark and terrible. So it went into a separate container.

My end goal with waste treatment is to become efficient to the point of it being self sustaining, with my only expense being NaOH and the HCl to adjust the pH. ...of course I will still have to source the iron, but, to call that an expense would be a gross exaggeration, since that is something that is free and very abundant (my father owns a fabrication/machine shop, father in law is a scrapper)

My aim is not to have any noble metals in my liquor by the time it gets to the sacrificial iron.
I have saved all the deposits, It looks very interesting with black powder as well as lots of nice copper outcroppings.
I am saving all my old oil so when I have the space for a large oil fired furnace I can melt it all in a big crucible to see what kind of alloy I get for as little cost as possible.
I am hoping that eventually I may have enough to send on to a copper refiner who will pay for the nickel as well. The only fly in the ointment of that plan is the shear volume of alloy you would need to make it happen.
May be a good retirement egg?
I buy copper for about £3 a kilo, I can not see a way to produce it from impure waste for less.

 

[aga]

Thanks Justin, aga, and anyone else who adds to this further

I have not even recovered 0.0001g gold yet, so anything i could add would be worthless.

As per the OP, is this looking 'normal' so far, or has it all gone wrong again ?

 

[aga]

Thanks Justin, aga, and anyone else who adds to this further

I have not even recovered 0.0001g gold yet, so anything i could add would be worthless.

As per the OP, is this looking 'normal' so far, or has it all gone wrong again ?

Edit: or do i just have to run the whole process and find out for myself ?
Maybe that's the best route on the first try - maybe can understand better why people do it different after trying the 'standard' way.

Edit: missed quote tag

 

[UncleBenBen]

Aga, this is one of those areas where Hoke's information kind of conflicts with processing escrap. She used zinc because she was processing mainly high PM materials with low base metal content.

With escrap it's just the opposite for the most part. By going to zinc in your case you dropped darn near every metal in the solution. That's why the two step stock pot is recommended. According to the reactivity series of metals copper will reduce the PM's leaving iron and most others in solution. After the PM's have cemented the solution can go to the next pot, leaving the values behind in the first. Then iron will cement the copper and most other metals so that the solution can go on to further waste treatment.

I think for what you have so far I would save the powders under water after rinsing well to remove as much acid as is practical and use those powders down the road to cement your newer stock pot later. That way the PM's that are already mixed can be recovered without trying to reprocess the powders now.

 

[aga]

Oh dear.

So i screwed it up again, already. Too much Copper in there.

May as well follow the Path (seeing as that's where i am already at with this batch) and find out where it leads.

The idea was to See all aspects of the process, but never thought it would wind up such a catastrophe !

Part of the idea was to see a tiny blob of Gold ... seems light years away now.

Thanks for the pointers El Diablo.

Edit: typo

 

[UncleBenBen]

:lol: :lol: :twisted:

Thanks for the pointers El Diablo.

Still funny!! I'll say it again, aga. Don't over think it. Collect up a nice pile of scrap, fingers, pins, whatever. Then follow the appropriate process as laid out. You will likely be surprised when it clicks and you see how easy it "can" be. Get through one run beginning to end.

Then apply your chemistry knowledge. (Of which I hope to learn a bit!)

 

[Topher_osAUrus]

Aga, you are doing fine. And are light years beyond were I was as a beginner.

Ben nailed it though, escrap isn't/wasn't Hoke's forte, but she wasn't in that era, so I don't hold it against her.

Zinc would be a good option for someone in a hurry, with cheap nitric, and very little base metals in the waste stream.. ..she had a disdain for silver (which I can understand why at times, but silver is beautiful in its own right.. If its not in chloride form :twisted: )

Justin, that is my plan too, to save up my little bits of pgm's and AgCl from AR runs and keep it for my rainy day/retirement fund. I believe I will follow the same path as Harold and use a good flux for silver chloride conversion and have it be the collector metal for the more precious ones. Then separate out the metals and run the silver through the cell. Afterwords running the cell slimes and pgm's to purity.

 

[nickvc]

Topher the one problem with using the silver cell with your PGM accumulations is that the palladium will go into solution in the silver nitrate which can plate out with the silver or will need cementing out, my advice is to keep the silver separate and collect any PGMs and gold in a separate stockpot. If you do that you can dissolve all the values precipitate the gold and cement out the PGM as blacks, you can further separate the Pd by then using nitric and cementing that out leaving any other PGMs behind as powder. Refining PGMs is inherently dangerous so in my opinion avoid that, any PGM in solution is risky so limit your exposure to as little as possible.

 

[g_axelsson]

Aga, I think you have started in the wrong end of the refining cycle. The stock pot is usually, and especially when Hoke's methods are considered, meant for accumulated values from refining.

What you have is a mess and I think you should look at those methods to recover the small amounts of values you have.

My first recovery of my stock pot was after I had refined over 50 grams of gold and I recovered about one gram from the stock pot. I never had more than half a liter of liquid in my stock pot. Coming from my refining it was never a lot of base metals in the liquids I put into it and I used copper to continuously cement any values in the stock pot.

When recovering and refining gold from electronic scrap you start by eliminate the base metals, then when you have a concentrate of gold or other precious metals you dissolve it and precipitate the gold. What you are left with is a weak pgm solution which sometimes contains both traces of dissolved gold and fine particles of metallic gold.

Since I'm running a lot of small scale experiments the 50 grams I had refined was from around 50 recoveries, so about 20 mg per lot went into the stock pot after I collected my gold.

My recommendation is don't follow Hoke and cement out values with zinc, your mess is full of base metals and then you will be back on square one, less the plastics but with a lot more waste.

Göran

 

[Justincase]

Topher the one problem with using the silver cell with your PGM accumulations is that the palladium will go into solution in the silver nitrate which can plate out with the silver or will need cementing out, my advice is to keep the silver separate and collect any PGMs and gold in a separate stockpot. If you do that you can dissolve all the values precipitate the gold and cement out the PGM as blacks, you can further separate the Pd by then using nitric and cementing that out leaving any other PGMs behind as powder. Refining PGMs is inherently dangerous so in my opinion avoid that, any PGM in solution is risky so limit your exposure to as little as possible.

Is not the silver cell where you tap off the Pt and Pd from your system in any case.
All my runs have a mix of Ag,Au,Pt,Pd,Rh in one combination or the other.
Just about all the PGM's find there way to my silver cell on the first go around the round about.
If anything there level has been greatly reduced from the system by the time any liquor gets to the stock pot in comparison to the first inquartation.
I Have found that if you let your spent gold liquor settle well first and are carefully with decanting you can recover all but forensic traces of Au from the A.R. digestions,I thought most of the extra value will have piggy backed into the silver chloride in all the junk and flux as undigested particles after my best effort to separate has failed to be 100% effective .
I will be running my slop in the weeks to come so I will see what kind of alloy the system produces.But I am expecting may be 10g Au to over a kilo of Ag and much less PGM as most have already been taped off in the cell slime and electrolyte,I do maintain my cell to prevent plating unwanted elements in any case
.

 

[Topher_osAUrus]

Topher the one problem with using the silver cell with your PGM accumulations is that the palladium will go into solution in the silver nitrate which can plate out with the silver or will need cementing out, my advice is to keep the silver separate and collect any PGMs and gold in a separate stockpot. If you do that you can dissolve all the values precipitate the gold and cement out the PGM as blacks, you can further separate the Pd by then using nitric and cementing that out leaving any other PGMs behind as powder. Refining PGMs is inherently dangerous so in my opinion avoid that, any PGM in solution is risky so limit your exposure to as little as possible.

I will most certainly follow that advice and keep my silver out of my stockpot then, and keep the agcl in its own bucket until it warrants refining. I only thought it may be good to do the way I mentioned, as its AgCl from AR runs, so it has gold in with it. But, I will keep them as separate as possilble. Thank you for the advice nick

 

[Topher_osAUrus]

Is not the silver cell where you tap off the Pt and Pd from your system in any case.
All my runs have a mix of Ag,Au,Pt,Pd,Rh in one combination or the other.
Just about all the PGM's find there way to my silver cell on the first go around the round about.
If anything there level has been greatly reduced from the system by the time any liquor gets to the stock pot in comparison to the first inquartation.
I Have found that if you let your spent gold liquor settle well first and are carefully with decanting you can recover all but forensic traces of Au from the A.R. digestions,I thought most of the extra value will have piggy backed into the silver chloride in all the junk and flux as undigested particles after my best effort to separate has failed to be 100% effective .
I will be running my slop in the weeks to come so I will see what kind of alloy the system produces.But I am expecting may be 10g Au to over a kilo of Ag and much less PGM as most have already been taped off in the cell slime and electrolyte,I do maintain my cell to prevent plating unwanted elements in any case
.

I see where nick is coming from, and your points as well. The Pd is a problem with the cell as its soluble in the electroyte and will codeposit with the silver crystal if it gets to a high enough % or gram per liter. So you would be forced to remake electrolyte, also separating the silver and palladium from the old one. -which is more work and a pain, as silver chloride is being created again.

My AgCl from AR digestions is basically in two "forms" -powder/cottage cheese curds, and crusts from goldfilled runs.... I may have a bit of a problem in the fact that, also there are Rhodium foils in the mix too, and according to Lou, Rh is not miscible in silver unless there is ample gold to put it in the matrix and hold it in the alloy so it doesn't phase out.

I cant wait to see/hear your results on doing your sludge run.
Is the majority of the material you run jewelry, escrap, ore, or...?

Have you ran your silver cell slimes at all? What were your results if so? A couple books I have report the numbers from refineries that run silver cells and the anodic sludge "impurities" they capture and refine... And I have read Harolds statement that he recovered roughly 1ozt of gold per 1000ozt silver ran through the cell.

I am sure it will be different per every individual, especially with the variety of scrap everyone is processing. Regardless, it's interesting to know and hear other's results.

 

[Justincase]

90% of my stock is scrap jewellery and one or two teeth a month.
I did do some electronics and other lot's last year,But on the hole I prowl the Auctions and have walk in clients.
Pt and RH are mostly in small quantity's as plating and setting's,the Pt mostly form the teeth and the odd bit of high quality white gold.
My primary turnover is the Au and then I have a nice chap who takes my Ag or that would not be profitable to do.
The Cell slime has just been building up,I some times run it through a sulfuric wash to reduce down the amount of Ag that has accumulated in the black over time.There is about half a 1000ml beaker unprocessed as is.
The Pd I remove from my cell once I have recovered the silver Nitrate by crystallization.the residue liquor is treated with DMG before cementing out the reaming silver to put back in the cell.
You either have to alter your processes each week or convince your stock to fit in with your established system.

 

[Topher_osAUrus]

The Cell slime has just been building up,I some times run it through a sulfuric wash to reduce down the amount of Ag that has accumulated in the black over time.There is about half a 1000ml beaker unprocessed as is.
The Pd I remove from my cell once I have recovered the silver Nitrate by crystallization.the residue liquor is treated with DMG before cementing out the reaming silver to put back in the cell.
You either have to alter your processes each week or convince your stock to fit in with your established system.

8) thats alot of cell slime...
What do you do with your sulfuric that has Ag in solution/ Silver Sulphate? I have read about a couple ways of reducing it down to metallic silver, but have yet to try it on my silver sulfide I have...maybe one day when silver skyrockets or I accumulate enough of it.

I like that idea of crystalizing out the silver nitrate and dealing with the pd that way. I was just going to convert to AgCl then cement or scavenge with dmg. But, your process sounds much better.
Thanks for that