When In Doubt, Cement It Out _cementation_

[J.Najam]

Hello again,

I did want to start a new thread but, we have here a perfect example as the name of this thread states it. I received these videos from a person who has made quite a mess and has been desperately trying to recover the PMs from this bucket. There are two buckets, the one containing the blue sediment is precipitate that resulted after having some of the solution decanted from the brown solution into this bucket and then the iron was added. Although it has now converted to crystal form because it had been left over for a year by now. The original bucket however (now brown sludge), contains the following :

Metals:
Mercury
Tin
Iron
Copper
Lead
Pd
Pt
Silver
Gold

Chemicals :
Nitric
HCL
H2SO4
NaOH
SMB

The starting material was electronics such as a couple of Ram boards, phone boards and (nokia and china). The availability of mercury came as a mercury nitrate waste and the platinum solution was a different experiment, (unable to precipitate) too ended up in here.

As far as I understand, this can be called a waste bucket, but with the presence of Sn, Hg, Pt and NaOH, I really couldn't suggest him any advice about treating this material.

So now, this case is over to you fine experienced refiners to help me help the guy clear his mess up.

Thanks for your time on this one.

 

[Yggdrasil]

Hello again,

I did want to start a new thread but, we have here a perfect example as the name of this thread states it. I received these videos from a person who has made quite a mess and has been desperately trying to recover the PMs from this bucket. There are two buckets, the one containing the blue sediment is precipitate that resulted after having some of the solution decanted from the brown solution into this bucket and then the iron was added. Although it has now converted to crystal form because it had been left over for a year by now. The original bucket however (now brown sludge), contains the following :

Metals:
Mercury
Tin
Iron
Copper
Lead
Pd
Pt
Silver
Gold

Chemicals :
Nitric
HCL
H2SO4
NaOH
SMB

The starting material was electronics such as a couple of Ram boards, phone boards and (nokia and china). The availability of mercury came as a mercury nitrate waste and the platinum solution was a different experiment, (unable to precipitate) too ended up in here.

As far as I understand, this can be called a waste bucket, but with the presence of Sn, Hg, Pt and NaOH, I really couldn't suggest him any advice about treating this material.

So now, this case is over to you fine experienced refiners to help me help the guy clear his mess up.

Thanks for your time on this one.

Where did the Mercury Come from?
Did he add it intentionally?

 

[J.Najam]

Where did the Mercury Come from?
Did he add it intentionally?

He's basically a placer gold prospector so he formed an amalgam of gold with mercury then treated the same with nitric for parting

 

[Yggdrasil]

He's basically a placer gold prospector so he formed an amalgam of gold with mercury then treated the same with nitric for parting

If it wasn't for the Mercury I'd dry it and roast it then to HCl.

 

[adam mizer]

Mercury should have been retorted out before anything.

 

[J.Najam]

If it wasn't for the Mercury I'd dry it and roast it then to HCl.

Yeah I know, I would've recommended smelting had it not been for the PGMs (given their melting temps) and mercury given the amount of acids he's used up as well (about 100's of USDs by now). These were his good time savings that were consumed in the process.

But what really should be the solution here?

P.S He added iron to the solution, how come we don't see nay mercury precipitate?

 

[Yggdrasil]

Yeah I know, I would've recommended smelting had it not been for the PGMs (given their melting temps) and mercury given the amount of acids he's used up as well (about 100's of USDs by now). These were his good time savings that were consumed in the process.

But what really should be the solution here?

P.S He added iron to the solution, how come we don't see nay mercury precipitate?

There are many metals in there so you may not see it.
Cementing is the solution here, let it cement out on Copper or Zinc.
When nothing more comes out you can dry the powder and prepare it for a retort.

I'd get/build a retort and run the powder through it.
Then you will be sure there are no more Mercury.

Then dissolve what can be dissolved in HCl, roast it and run the rest in Nitric.
You should now have only Pt and Gold left in the powders.
Drop the Silver as Chloride and drop the Pd with DMG if its not too much.
Gold Pt powders can be separated the usual way.

 

[J.Najam]

Cementing is the solution here, let it cement out on Copper or Zinc.

Got it, will ask him the same.

A couple of questions though :
1, He'll need to hydrate it a little to create room for cementation right? If yes, which liquid should he use : HCl or nitric?

2, Should both the buckets be combined into one before the process given he's used Iron in the 2nd bucket already?

I'd get/build a retort and run the powder through it.
Then you will be sure there are no more Mercury.

Ill have to learn this technique myself first before teaching him how to do it

 

[Yggdrasil]

Got it, will ask him the same.

A couple of questions though :
1, He'll need to hydrate it a little to create room for cementation right? If yes, which liquid should he use : HCl or nitric?

2, Should both the buckets be combined into one before the process given he's used Iron in the 2nd bucket already?


Ill have to learn this technique myself first before teaching him how to do it

How large are the buckets?

 

[J.Najam]

How large are the buckets?

I have shared the videos earlier, I think they're probably the 15 litre ones

 

[Yggdrasil]

I have shared the videos earlier, I think they're probably the 15 litre ones

Is there Mercury in both?
The one cemented on Iron, test the liquid for PMs and if barren, divert the liquid to the waste stream.
The one not cemented on Iron, same test the liquid, if barren the same.
When the one containing Mercury has been retorted clean, join it and roast again.
Now process as normal, HCl first, roast the solids, Nitric filter out the Solids test the Liquid and so on.

 

[J.Najam]

divert the liquid to the waste stream.

One bucket now has crystals and the other is a sludge... would a water rehydration be a good choice to check for PMs testing?

 

[Yggdrasil]

One bucket now has crystals and the other is a sludge... would a water rehydration be a good choice to check for PMs testing?

Stannous need a acidic Silver free solution so use HCl.

 

[J.Najam]

Stannous need a acidic Silver free solution so use HCl.

Got it, will have some HCl added - stannous check - then proceed with cementation as required. Dry - roast - chemicals? correct?

 

[J.Najam]

When the one containing Mercury has been retorted

Please correct me if Im wrong, if we have all the dry powders in the retort, would the heat just evaporate the mercury that later forms as a solid-liquid mercury distillate?

 

[Charles Drummond]

Please correct me if Im wrong, if we have all the dry powders in the retort, would the heat just evaporate the mercury that later forms as a solid-liquid mercury distillate?

The gold amalgam will give off mercury vapor. If you use Nitric acid dilute, will remove the mercury. Adding copper will let you pull the mercury out, then add zinc to get the copper out and lime stone to get a safe combination to put down the drain.

 

[Yggdrasil]

The gold amalgam will give off mercury vapor. If you use Nitric acid dilute, will remove the mercury. Adding copper will let you pull the mercury out, then add zinc to get the copper out and lime stone to get a safe combination to put down the drain.

Read the thread dealing with waste!
This is not sufficient.

 

[Yggdrasil]

The gold amalgam will give off mercury vapor. If you use Nitric acid dilute, will remove the mercury. Adding copper will let you pull the mercury out, then add zinc to get the copper out and lime stone to get a safe combination to put down the drain.

Welcome to us by the way.
Here are the links needed to read and study including dealing with waste.

We ask our new members to do 3 things.
1. Read C.M. Hokes book on refining jewelers scrap, it gives an easy introduction to the most important chemistry regarding refining.
It is free here on the forum: https://goldrefiningforum.com/phpBB3/viewtopic.php?f=54&t=19798
2. Then read the safety section of the forum: https://goldrefiningforum.com/forums/safety.47/
3. And then read about "Dealing with waste" in the forum: https://goldrefiningforum.com/threads/dealing-with-waste.10539/

Suggested reading:
https://goldrefiningforum.com/forums/the-library.101/
https://goldrefiningforum.com/threads/when-in-doubt-cement-it-out.30236/
https://goldrefiningforum.com/threa...le-read-this-before-you-post-about-ore.33333/


Forum rules is here.
https://goldrefiningforum.com/threads/gold-refining-forum-rules.31182/

 

[Fettigconstruction1@gmail]

Will cementation work in a thiosulphate solution with the use of copper for gold and silver precipitation?

 

[FrugalRefiner]

Well, first, that looks like a lot of copper. If you're cementing with copper, it shouldn't look like that.

An amalgam bead? Is there mercury in the mix?

I'm not sure what you're doing.

Dave