Refining NASTY waste... Decided to break from wisdom and do a weak AR bath as a recovery step... Thoughts?

[evanJ]

I'm refining some e-waste, and I decided to do a boil in 50/50 nitric & distilled water to start things off.
This left me with a viscous red/brown sludge... The solution definitely has copper, silver, and lead - and not all of the pins are dissolving despite adding a good bit of nitric.

The sludge is too viscous to filter off with my setup (we're talking one drip per 30 seconds, and I have a liter of sludge)

So I decided to do a warm AR bath with everything. My thought is that I will hopefully be able to filter it more easily, then take whatever crashes out with SMB and do another nitric bath for my precipitate + any remaining solids from my original slurry, and then proceed from there with another AR step.

Does that sound like it will work?

I'm honestly regretting this one as I don't expect to get more than a gram or 1.5 max... but I feel like I'm in too deep to stop lol.

Thanks!

 

[Yggdrasil]

I'm refining some e-waste, and I decided to do a boil in 50/50 nitric & distilled water to start things off.
This left me with a viscous red/brown sludge... The solution definitely has copper, silver, and lead - and not all of the pins are dissolving despite adding a good bit of nitric.

The sludge is too viscous to filter off with my setup (we're talking one drip per 30 seconds, and I have a liter of sludge)

So I decided to do a warm AR bath with everything. My thought is that I will hopefully be able to filter it more easily, then take whatever crashes out with SMB and do another nitric bath for my precipitate + any remaining solids from my original slurry, and then proceed from there with another AR step.

Does that sound like it will work?

I'm honestly regretting this one as I don't expect to get more than a gram or 1.5 max... but I feel like I'm in too deep to stop lol.

Thanks!

I'd incinerate/roast it and then try a HCl bath to see if it dissolves anything.
If it is filterable then roast it again and go to Nitric again.
Next time start with Cupric Chloride aka AP.

 

[anarxi]

I'm refining some e-waste, and I decided to do a boil in 50/50 nitric & distilled water to start things off.
This left me with a viscous red/brown sludge... The solution definitely has copper, silver, and lead - and not all of the pins are dissolving despite adding a good bit of nitric.

The sludge is too viscous to filter off with my setup (we're talking one drip per 30 seconds, and I have a liter of sludge)

So I decided to do a warm AR bath with everything. My thought is that I will hopefully be able to filter it more easily, then take whatever crashes out with SMB and do another nitric bath for my precipitate + any remaining solids from my original slurry, and then proceed from there with another AR step.

Does that sound like it will work?

I'm honestly regretting this one as I don't expect to get more than a gram or 1.5 max... but I feel like I'm in too deep to stop lol.

Thanks!

you have tin, aluminum and iron there.
if you boiled your 50/50 solution for a long time, then the water simply boiled away.
and the solution turned into jelly.
Do not forget ,that you need 400 ml nitric acid dissolve 100 grams of material .

 

[anarxi]

if you have silver there, it will precipitate chloride and spoil all the aqua regia.
add sulfuric acid to nitric acid, it will not touch gold, but will dissolve everything else

 

[evanJ]

Thank you for the metal IDs! It really is a gross mess. Never thought I'd shudder at a rainbow.

if you have silver there, it will precipitate chloride and spoil all the aqua regia.
add sulfuric acid to nitric acid, it will not touch gold, but will dissolve everything else

Why would silver spoil the AR? My plan was to filter the AR before adding SMB, and then further refine the precipitate with a nitric bath and possibly another round of AR.

Shouldn't the silver chloride be able to easily filter out?

I don't have sulfuric but I could get some if necessary. Just don't want to invest too much $$$ in this recovery since I'm not expecting a lot of gold.

I also was hoping to spend all of my nitric because I can't store it long term, hence my liberal usage of it

 

[Yggdrasil]

Thank you for the metal IDs! It really is a gross mess. Never thought I'd shudder at a rainbow.


Why would silver spoil the AR? My plan was to filter the AR before adding SMB, and then further refine the precipitate with a nitric bath and possibly another round of AR.

Shouldn't the silver chloride be able to easily filter out?

I don't have sulfuric but I could get some if necessary. Just don't want to invest too much $$$ in this recovery since I'm not expecting a lot of gold.

I also was hoping to spend all of my nitric because I can't store it long term, hence my liberal usage of it

Silver Chloride separates nicely out if your solution is clean.
But yours are not, right?
The moment any Chloride is introduced into Nitric with Silver it drops out.

 

[anarxi]

silver is in dissolved form in your solution.
and aqua regia contains hydrochloric acid, which will convert silver into chloride.

Instead of sulfuric acid, you can use electrolyte for lead batteries.
In general, this is a classic of the genre, the first treatment with nitric and sulfuric acids.
or ammonium nitrate from a garden store and electrlit from a parts store.

 

[evanJ]

OK just confirming! I was intending for the silver to precipitate out so I can filter it out. This would be just to have a cleaner starting point for the refining process, as opposed to the final AR solution.

I do actually have a bottle of ammonium nitrate from my pyrotechnic days - in theory I could also make the sulfuric because I have sulfur and KNO3, but honestly that sounds above my pay grade lol. I'll look into the ammonium nitrate.

Thanks for the responses!

 

[Yggdrasil]

OK just confirming! I was intending for the silver to precipitate out so I can filter it out. This would be just to have a cleaner starting point for the refining process, as opposed to the final AR solution.

I do actually have a bottle of ammonium nitrate from my pyrotechnic days - in theory I could also make the sulfuric because I have sulfur and KNO3, but honestly that sounds above my pay grade lol. I'll look into the ammonium nitrate.

Thanks for the responses!

Depending of the amount and kind of E waste there may be no Silver at all.
And not Ammonium Nitrate but Ammonia which is Ammonia Hydroxide.
I'd just let what ever Silver if any in solution just be there.

 

[evanJ]

Thanks for clarifying!

I did a filtration and got a very weak stannous test. The filtered fluid is a deep dark green.
I split it into two batches and added a small amount of SMB to one, and am letting it settle overnight.

I'll update this post when I'm able to get everything cleaned up... So far, I'm really not a fan of e-waste. I'm producing so much waste compared to my karat scrap run, and will have so much less to show for it.

I agree about discarding any silver - it won't be worth more than a dollar if there's any there at all.