Zinc cementation on CCs Leachate.

[Hurc]

Hi
I am trying to extract precious metals from Catalytic cimverters. I leached the Converter with HCl H2O2 mixture.
1-) Filter the leachate and add ammonium chloride and got Platinium salt.
2-) Then I cememt the remaining filtered solition with zinc.
3-) I got some fine powder of metals. I was expecting it to be Zn, Pd and Rhodium.
4-) Than I filtered the metal powder and use HCl (20% diluted with tap water) to remove the base metals from this metal powder. I got green solution as seen in attached pic of graduated cylinder.
5-) About 90% of metal powder was dissolved in HCl. Than after washing the remaining powder with hot water two times. I use 50% dilited HNO3 to further remove any remaining base metals. HNO3 colour change to orange as can be seen in attached pic in flat bottom flask.
6-) HNO3 dissoved 90% powder. Very small amount of powder remained. Which I filtered as can be seen in attached pic of filter paper.
7-) I thaught HNO3 dissolved Pd as well. So I further process HNO3 and increase its PH to 12 with KOH. I was expecting brown precipitate of Palladium oxide but I got light greenish colour precipitate as seen in attached pic of 500ml beaker.
I further process this green precipitate by filtering, washing and adding formic acid. I was expecting that Formic acid will metalise the Pd but all precipitate dossolved in Formic acid.

My question is
1-) Which metal turn my HCl solition green.
2-) Where is Palladium? Am I right that HNO3 dissolve my Pd while HNO3 was diluted. Or HCl dissolve my Pd?
3-) Should I expect rhodium on Filter paper?

 

[eaglekeeper]

I may have missed it, but did you do any stannous testing through out that process?

What information do you have that indicates that Pd/Rh is even present?... It would be extremely difficult to put Rh into solution without proper equipment.

I have bought and processed lots of converters and I have yet to find one that test positive for Pd. All the one's I've processed so far were Pt only.

 

[Sancho_n_Pedro]

I may have missed it, but did you do any stannous testing through out that process?

What information do you have that indicates that Pd/Rh is even present?... It would be extremely difficult to put Rh into solution without proper equipment.

I have bought and processed lots of converters and I have yet to find one that test positive for Pd. All the one's I've processed so far were Pt only.

Just out of curiosity, how much Pt would you get out of one Cat converter, or would it depend on the model?

 

[Hurc]

Just out of curiosity, how much Pt would you get out of one Cat converter, or would it depend on the model?

It depends on models. Experienced people know which model has most pgms. I heard catalytic converters of petrol based cars have much precious metals while people usually not intrested in diesel based cars catalytic converter ( I heard it from peoples who sell CCs). I still have pt in salt form so i can not tell you how much I got.

 

[Hurc]

I may have missed it, but did you do any stannous testing through out that process?

What information do you have that indicates that Pd/Rh is even present?... It would be extremely difficult to put Rh into solution without proper equipment.

I have bought and processed lots of converters and I have yet to find one that test positive for Pd. All the one's I've processed so far were Pt only.

 

[Hurc]

It needs experience to know which models of CCs have which metals. Its my first time to process so I am not confirmed that which metals I have in my solution. I did not use stannous for testing. I am not confident with this test as I never did that.

 

[eaglekeeper]

Just out of curiosity, how much Pt would you get out of one Cat converter, or would it depend on the model?

It does depend on the model and how long it's used. The Cat's degrade over time and start sluffing off some of the PMG's..... how much is the question. It would be hard to give you a good yield number because my numbers vary so much. The Cat's I buy are beyond they're useable life so I usually pay no more than 1 gram of Pt price, most of the time I make a little profit, but not much.

Catalytic converter theft is through the roof right now and if the person you buy from gets caught....be ready for a possible knock at your door. Make sure the people you buy from are trustworthy.

 

[Sancho_n_Pedro]

ok guys, seems like its a bit of a risk, and no defined list of ones to acquire. I have 2 that came from my mechanic who removed them, one was past its best and the owner wanted it replaced, the other one was put on the wrong car, so he removed it, replaced it with the right one, but then the supplier would not take the original one back as it was technically "used". He couldn't remember what model car it came from either, so was stuck with trying to sell it on to anyone. My mechanic has closed his garage now, so I got these as he I helped him clear all his junk from the garage prior to him closing the place.
There might be no point doing anything with them but still as a learning exercise I might just see what comes from them both.

 

[eaglekeeper]

My 2 cents...... Some may disagree, but I don't recommend crushing/grinding Cat's into a powder (unless you're smelting). The PMG's are only on the surfaces and it is much easier to handle one piece rather than a powder. The powder makes filtering a pain in the butt. Plus there is a constant risk of accidently breathing in the dust...not good for you.

There's many ways to reduce the metals, but I find cementing on Zinc is the most easiest/cost effective. I get those Zinc electrical conduit fittings from the hardware store. Make sure they are the Zinc and not the steel one's. The jam nuts/screws on those Zinc one's can sometimes be steel.

I am usually disappointed with the yields on used OEM Cat's and the "universal" Cat's suck even more.

PGM's solutions are very toxic in case you didn't know..... please do some research.

 

[Liquidau]

I processed 10 CCs last year. For sure don’t crush them up, the dust is unhealthy, it makes them harder to handle, and it makes filtering later really difficult.
Gasoline vehicles use Pd rich CCs, while diesels have more Pt. All have Rh but very little of it by weight. They contain NO GOLD.

Follow Sreetips on YouTube. Use mostly HCl and a bit of H2O2 or bleach. Cover and stir daily, adding a bit of bleach. The deeper the red colour the better. Filter.
Drop all PGMs with zinc. Filter and wash. Then redissolve in AR to concentrate them. Denox . Now drop Pd with DMG (or chlorine gas from a bubbler) or Pt with ammonium chloride.

I got 5g of Pd, although I probably lost some in extraction and processing. Hard to make a profit unless you have known high yield CCs and know what you’re doing.