Aluminum usage for Pd nitrate

[kjavanb123]

All,

Up until today I have been using zinc powder to precipitate palladium black from nitrate solution.

It was rather expensive and time consuming, since we produce large volumes of Pd nitrate solution as result of our smelting process, yesterday I tried aluminum to replace zinc and it worked great.


My source for aluminium was heatsink we removed from the boards during depopulation.

You then add one or two of them to nitrate solution, and add some ml of hcl to this, until fizzing starts, then you just add few more pieces to solution and let it dissolve.

As they dissolve in produced aqua regia, aluminum goes in and palladium comes out.

Return in half and hour, all aluminum pieces are gone and solution color changed to grayish, collect the Pd black.

Hope that helps someone.

Kj

 

[Geo]

Yes, it works about as good as zinc. My problem is, I can only get it pure to a certain point by cementing and and you really can't get it any purer. I tried to refine the salts and got in over my head. It didn't end the way I had hoped it would. I still have the black powders from the batch. It's not very pure though. I know that as soon as I try to melt it, copper will turn the dish black. I really hate that because all my dishes is nice and clean. I haven't melted anything that dirty in awhile. I guess it's time to dirty one of them up. Prices are up now.

 

[kjavanb123]

Geo,

Pd produced using aluminum as I tested today come up a lot cleaner, than when I used zinc powder.

You can always refine the Pd black by dissolving in nitric, precipitate using DMG, then convert the yellow powder using formic acid method.

Regards
Kj

 

[Elektrikis]

For paladium nitrate. Ad sodium bicarbonate. Boil liqud ad formic acid. Paladium drop black.

 

[kjavanb123]

For paladium nitrate. Ad sodium bicarbonate. Boil liqud ad formic acid. Paladium drop black.

Can you elaborate on that please?

 

[Lino1406]

If palladium is the only constituent, I think the following are better choices: 1)To have some HCl inside - agreed. Then de-nox with sulphamic acid or ammonium sulphamate. Then - Al. Or 2) De-nox and precipitate with NaOH + CH2O as PdO/Pd. I found no evidence of explosive formation although de-noxing is probably not complete (unlike the case for silver)

 

[Geo]

I suppose it is subjective to how much of other metals is in the solution. Zinc and aluminum cement copper, along with a long list of other metals. After you cement with copper, the amount of copper left would be hard to remove by cementing with any other metal.

Here is a notion, I don't know how well it would work. Take the palladium nitrate and add a small amount of sulfuric acid. Now you can distill the nitric acid from the solution. Would the palladium convert to palladium(II) sulfate? Can't it be plated out onto a palladium target?

 

[kjavanb123]

Mine has only palladium as final product of smelting is silver alloyed with palladium and gold.

So no other base metals present in the solun

I think sulfuric acid treatment may work, habe not tried it yet.

 

[Nadeem]

For paladium nitrate. Ad sodium bicarbonate. Boil liqud ad formic acid. Paladium drop black.

Its for small quntity what abt for 28 litere

 

[Yggdrasil]

Its for small quntity what abt for 28 litere

This can be used for large volumes too.
You just have to have enough head room for foaming, so use many vessels with a couple of litres each.
Similar procedure is described in Hokes book.

 

[beetech]

Hello, it's a pleasure to greet you, I would like to know if you could guide me, I have a solution of palladium in nitric acid, mostly dirty with iron-based metals, what would be the easiest procedure to recover the palladium from the nitric solution, I would have to DENOX the nitric evaporating it by adding HCL, or sulfamic acid, or urea? and then cement with copper or zinc, or reduce with formic and sodium carbonate? I hope you can guide me thank you very much

 

[Yggdrasil]

Hola, es un placer saludarte, me gustaría saber si podrías guiarme, tengo una solución de paladio en ácido nítrico, principalmente sucio con metales a base de hierro, ¿Cuál sería el procedimiento más fácil para recuperar el paladio de la solución nítrica? ¿Tendría que DENOXAR el nítrico que lo evapora agregando HCL, ácido sulfámico o urea? y luego cemento con cobre o zinc, o reducir con carbonato de sodio y fórmico? Espero que puedas guiarme muchas gracias

If you want answers, post in english please.

 

[beetech]

If you want answers, post in english please.

Hello, it's a pleasure to greet you, I would like to know if you could guide me, I have a solution of palladium in nitric acid, mostly dirty with iron-based metals, what would be the easiest procedure to recover the palladium from the nitric solution, I would have to DENOX the nitric evaporating it by adding HCL, or sulfamic acid, or urea? and then cement with copper or zinc, or reduce with formic and sodium carbonate? I hope you can guide me thank you very much

 

[beetech]

What would be the simplest procedure to recover the palladium from the nitric solution, to make a metal bar to sell it to refiners? cement it with copper?

 

[Yggdrasil]

Hello, it's a pleasure to greet you, I would like to know if you could guide me, I have a solution of palladium in nitric acid, mostly dirty with iron-based metals, what would be the easiest procedure to recover the palladium from the nitric solution, I would have to DENOX the nitric evaporating it by adding HCL, or sulfamic acid, or urea? and then cement with copper or zinc, or reduce with formic and sodium carbonate? I hope you can guide me thank you very much

You know that PGM salts are very toxic I hope.
What material do it come from?
Have you tested it with stannous?
That is a start I guess.

 

[beetech]

If the toxic thing I take into account, that's why I don't want to refine it, I just want to get it out of the solution to sell it to the refinery, if the tin test shows dark black

 

[Yggdrasil]

If the toxic thing I take into account, that's why I don't want to refine it, I just want to get it out of the solution to sell it to the refinery, if the tin test shows dark black

The moment you put it into solution it is dangerous.
As metal it is not.
Where did it come from?
For Pd it is supposed to be dark greenish, so if it is black dilute it and try again.

 

[beetech]

nitric palladium solution
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try cementing with copper


filtered liquid after adding copper and did not make more reaction

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brown residue with copper flakes


tin test before starting cementation
View attachment VID-20221227-WA0044.mp4


View attachment tin.mp4

 

[Yggdrasil]

View attachment 53891
nitric palladium solution
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View attachment 53894
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try cementing with copper

View attachment 53892
filtered liquid after adding copper and did not make more reaction

-----------------------------------------------------------
brown residue with copper flakes
View attachment 53893

tin test before starting cementation
View attachment 53895


View attachment 53896

You have still not explained why you expect it to have Pd in it.
What the source material is.
Cementing with copper needs intense stirring or bubbling.

 

[beetech]

the stannous chloride test is not positive? for palladium