sodium chlorate - palladium process

[Rotz]

Hello GRF,

I took black powder from my stock pot, saturated with copper. Then with AR I took the gold. When I see dark brown color at stannous. Then add until saturated with ammonium chloride, nothing show up. Then I add sodium chlorate, greenish yellow salt show up. photo is below. Stannous give negative.

Normally palladium salt looks red but this is yellow. Then I researched the forum. At past, HaroldV had been expressed with photo. it is yellow with sodium chlorate. Then He told if you apply with ammonia step it will be red. Must I apply ammonia step or can I roast directly.

 

[Martijn]

Pd expected solution? Gloves? :!: :!:

Hi Rotz, what was saturated with copper? The solution or the black powder?
If you have a lot of copper in your pregnant solution the copper can give a false positive with stannous.
Dilute the drop you test to see the color better.
Martijn.

 

[Rotz]

Hello Marjtin,

I just took a photo so had not gloves. I put copper to my stock pot. Then I took a lot of black powder deep. Dissolve it with hcl and peroxide. When I check stannous I saw purple. Then I precipitate the gold with copperas. Then I saw brown with stannous. It is a like caramel color. Then I added ammonium chloride. Nothing happen and stannous show still same color. I add a lot of when the solution about 40 C. Nothing show up. Stannous still same. So I add sodium chlorate for Cl supplier. Then this material show up. Stannous been negative. I couldnt tell well explained sorry about that. Sometimes I think you know this step and I dont tell all of detail. It is because of my excited. So I tried to see the stannous test again I dissolve a little bit this yellowish sediment in hcl. It didnt give positive result. It is looks like palladium salt but everybody have red I have yellowish. Which process I need to continue. Than you for helping.

 

[Rotz]

By the way I know false positive result. It is not that.

 

[Rotz]

Pd expected solution? Gloves? :!: :!:

Hi Rotz, what was saturated with copper? The solution or the black powder?
If you have a lot of copper in your pregnant solution the copper can give a false positive with stannous.
Dilute the drop you test to see the color better.
Martijn.

I saw this post today. It is quite similar color. Should I apply ammonia and hcl to make red ?

 

[Rotz]

This is the color of stannous before it precipitated.

 

[Martijn]

Sorry, that was all I could contribute. No practical experience with Pd. You need more knowledgeable members to respond here.
good luck

 

[Rotz]

Thank you I hope I can refine

 

[Yggdrasil]

The stannous looks like "false positive" to me.
In my humble not too experienced world I would guess copper or something like that.
You can see the "clear" liquid with the brown precipitate in it.

 

[Rotz]

I don't think false positive. I tried my dust again with the same method. After I precipitate the gold, stannous showed this color again. When this sponges showed up after sodium chlorate, stannous turned negative.

 

[Yggdrasil]

I could not find the link just now, so I hope I'm forgiven.
This picture comes from one of LazerSteves threads.


And this for Rhodium from same thread


I can't see any of these colors in your test..
Do anyone else have an input here?

 

[kurtak]

The method you are using to precipitate Pd from a solution "requires" the solution to be very concentrated

The reason for that is that you are trying to precipitate the Pd as a salt and that salt is actually water soluble

So if the solution has water in it - and depending on how much water is in the solution - you "may" get "some of the salt to precipitate - or it may not precipitate at all

You posted -------

When I see dark brown color at stannous.

And then you also posted --------

Then I saw brown with stannous. It is a like caramel color.

That is NOT the right the right color for a positive Pd stannous test

A positive Pd stannous test should show up as a dark green --- when you first do a Pd test with stannous it will show a orange/red color but will then quickly turn to a dark green (think forest green) there is such a thing as a "false" positive for Pd - but that will show up as a "light" green (think lime green)

So if your stannous test is brown it is likely not Pd

When you do a stannous test - and you THINK it is Pd --- you should ALWAYS follow the stannous test up with a DMG test --- other wise you can end up chasing your tail looking for Pd that just is not there

There are a number of false positive stannous test that you can get which I posted about here

:arrow: Cement

read that post as well as the one right after that one

Kurt

 

[kurtak]

I could not find the link just now, so I hope I'm forgiven.
This picture comes from one of LazerSteves threads.

Au_Pt_Pd_Stannous.jpg
And this for Rhodium from same thread
pt_rh_test.jpg

I can't see any of these colors in your test..
Do anyone else have an input here?

Thanks for posting that Yggdrasil - I have been looking for those pics recently to put in some of my other replies in other threads & was unable to find them 8)

Kurt

 

[Rotz]

Thank you guys, I have a question.

Platinum & palladium salts can turn to type of in AR again? I mean If I change my mind after see platinum or palladium salt then can I turn back to solution then can I choose cementation method. Is this possible?

 

[Lou]

Redissolution is an option on the ammonium-containing salts with great heating and concentrated aqua regia it is possible to oxidize the ammonium (NH4+) cation and even the ammonia ligand (NH3). It is not a recommended practice whatsoever because of the NOx formation, the misting, and the risk for NCl3 production in certain circumstances.

 

[Rotz]

I see. Another question
Platinum salt doesn't dissolve in HCl as I read. When I dissolve in water. Should it make stannous positive ?

Palladium salt can dissolve HCl and water. Dissolved salt in these solutions should have make stannous positive?

Learning something neither too easy nor too hard if you have a lot of question in mind.

 

[Yggdrasil]

Just happy to give back some Kurtak!

 

[Rotz]

Hello

I tried drying the sponges. Then burn. Then melt. But just green residue I have. Then I learn purifying with ammonia. Remain material added ammonia. I saw very blue solution. Then add hcl. This is result.



I will purify with ammonia again. I bought dmg. Tomorrow check with dmg.

This title very nice to learn;
PGM Recover & Refining: Unknown green powder precipitated

Pd purifying in pictures

 

[Rotz]

Hello
To the conclusion, I dissolve the colorful sponge with ammonia again. Then I precipitate wlth dmg. I dont know why but it didnt precipitate as yellow sponge. I roast. Now I am searching pot to melt.

 

[Yggdrasil]

I have not seen a positive stannous test yet, do you have any PMs in solution at all?