• Refining Palladium concentrates.

[FrugalRefiner]

Unfortunately, 9kuuby9 was unjustly banned many years ago.

Dave

 

[Yggdrasil]

hllow 9kuuby9, hope i`ts great, this process can be used to recover capactors pownder, where there are impurities such as cooper, silver, etc dissolved in nitric ? and congratiulation for ecxellent work.

The member is banned, so he will not see this.
Edit, Dave beat me to it.

 

[Pd_chemist]

The carbon, burn. It gives PdO plus silicates from the ash. Reduce that with formic acid, then digest in aqua regia.
Filter out the residues, rinsing til colorless and add them to the PdCl2, Pd acetate, etc. and reduce with ammonium formate at pH of 3.5. You will have pure Pd metal

Thank you for your reply.

I'm currently burning/ashing the Pd/C 10% wet at 450°C. It works great in my homemade electric furnace. I'm performing the ashing in a steel container (1cm high). Off course the steel itself also gets oxidized fast at this temperature resulting in black flakes. So the PdO will also be contaminated at the moment with this iron salt. Does iron reduces as easily as palladium with formic acid? If yes, removal of the iron by a magnet should do the trick to remove traces.

You mention to rinse the residue after dissolution with aqua regia till colorless filtrate. Should it be rinsed with aqua regia or just water?

How critical is the pH for the reduction with ammonium formate? Why not use also here formic acid?

I'm also thinking of making a stirred crucible. But first have to see which material would be suited to connect the stirring shaft to the motor ifo heat transfer.

 

[Lou]

Get a silica or alumina dish, or even better, pyroceram from Corning. Iron oxide is not easily reduced away and do not use a magnet--this is too high of a grade to risk doing that to. You would tare the dish and burn this until the mass loss is constant and there is no gain (Pd-->PdO)
You would rinse the digested cake with water not aqua regia.

The pH of 3.5-6 region works best. The ammonium formate makes a better precipitate, but formic acid can also be used.
You can almost look at palladium and reduce it to metal.

Don't make a stirred crucible.

 

[Pd_chemist]

Pyroceram? If I google it, it seems to be an oven dish? Have to talk to the wife I guess...

 

[snail]

Corning white oven dishes with an item number beginning with a P. Some of the newer products start with an A and are inferior for extreme uses.

 

[FrugalRefiner]

See What will hold up? Pyroceram.

Dave

 

[Pd_chemist]

I'm trying to read more into the topic of Palladium recovery and found this old post: 2% Palladium on Carbon

In my practice the best method to recover Pd was to burn down as much carbon as possible, followed by tempering the remaining "ash" at about 600oC under good aeration.
Under these conditions Pd-metal takes up oxygen to form PdO, which eventually is reduced by carbon, still present in the mixture. Heating to 800oC - 900oC leads to thermal decomposition of PdO to the metal and elemental oxygen. Thus, repeating the tempering/oxidation - thermal decomposition cycle leads, after a last decomposition step under exclusion of oxygen, to Pd-sponge containing only minute amounts of carbon.

I'm performing the ashing procedure at 450°C in my electric furnace till all glowing stops. Do I rally need to go to 600°C?

The carbon, burn. It gives PdO plus silicates from the ash. Reduce that with formic acid, then digest in aqua regia.
Filter out the residues, rinsing til colorless and add them to the PdCl2, Pd acetate, etc. and reduce with ammonium formate at pH of 3.5. You will have pure Pd metal

Which solvent do you suggest to perform the reduction of PdO with formic acid? Methanol?

 

[amirfmpz]

سلام دوستان من تعدادی سنگ حاوی پالادیوم دارم.
اما من از شیمی زیاد بلد نیستم و مواد شیمیایی را آماده کردم و می خواهم پالادیوم را از ابتدا استخراج کنم.
لطفا من را راهنمایی کنید> با تشکر

 

[Yggdrasil]

سلام دوستان من تعدادی سنگ حاوی پالادیوم دارم.
اما من از شیمی زیاد بلد نیستم و مواد شیمیایی را آماده کردم و می خواهم پالادیوم را از ابتدا استخراج کنم.
لطفا من را راهنمایی کنید> با تشکر

Welcome to us.
But post in English please, this is an international forum.

Here is for your studies.
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: Screen Readable Copy of Hoke's Book
2. Then read the safety section of the forum: Safety
3. And then read about "Dealing with waste" in the forum: Dealing with Waste

Suggested reading: The Library

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

 

[amirfmpz]

thank you

 

[amirfmpz]

Hi, I have palladium/silver deposits
How to separate palladium from silver?

 

[Yggdrasil]

Hi, I have palladium/silver deposits
How to separate palladium from silver?

I often reply with "How long is a rope" to this kind of questions.
You do not give us enough information to let us help you.

How do you know that you have Silver and Pd in solution?
What is your starting material?

 

[amirfmpz]

I often reply with "How long is a rope" to this kind of questions.
You do not give us enough information to let us help you.

How do you know that you have Silver and Pd in solution?
What is your starting material?

I first ground 20 grams of palladium ore completely
Then I dissolved the material in dilute sulfuric acid and then washed
I redissolved the material in dilute hydrochloric acid and washed again
And then I completely dissolved the ingredients in nitric acid
And a mistake!!!!! I deposited all the materials with aluminum
Now I don't know how to separate palladium from silver>>!
If I dissolve the precipitate in concentrated hydrochloric acid, will the palladium be separated from the silver????

 

[Yggdrasil]

I first ground 20 grams of palladium ore completely
Then I dissolved the material in dilute sulfuric acid and then washed
I redissolved the material in dilute hydrochloric acid and washed again
And then I completely dissolved the ingredients in nitric acid
And a mistake!!!!! I deposited all the materials with aluminum
Now I don't know how to separate palladium from silver>>!
If I dissolve the precipitate in concentrated hydrochloric acid, will the palladium be separated from the silver????

HCl do not dissolve Silver nor Palladium.
How do you know the ore contains precious metals?
How did you test the leach liquor for values?

 

[amirfmpz]

HCl do not dissolve Silver nor Palladium.
How do you know the ore contains precious metals?
How did you test the leach liquor for values?

I live in a place where there are copper, gold, etc. mines. I always dissolved this stone in acid, and before I added urea to the acidic solution, the solution's stannous chloride test was positive. But when I applied urea, the stannous chloride test was negative. And I asked an expert, and he said that you have palladium in the solution, not gold.

 

[Yggdrasil]

I live in a place where there are copper, gold, etc. mines. I always dissolved this stone in acid, and before I added urea to the acidic solution, the solution's stannous chloride test was positive. But when I applied urea, the stannous chloride test was negative. And I asked an expert, and he said that you have palladium in the solution, not gold.

That is no proof of anything.
What did you use for dissolving the "Stone"?
AR?
How did you use the AR?
Do you know how pregnant Pd looks like in a Stannous test?

Please describe your process in more detail.
If you have pictures it would be nice.

 

[amirfmpz]

First, I put the stone on the fire for 3 hours so that I could crush it more easily. Then I turned the stone into powder and put the stone powder on the heat for 1 hour so that if there was any sulfur, it would disappear. Then I poured the powder into the mortar. And I added dilute hydrochloric acid to the powder and put it on low heat and then emptied the solution and washed the powder several times. I also did this with dilute sulfuric acid and washed it again. I added ingredients and put it on heat and dissolved the powder in AR./ Here, when I took the stannous chloride test, it was positive, but when I added it to the urea solution and took the test, it was negative./ And I had many questions, why did this happen?!! 》And when I asked the person who was this expert, he told me that you have palladium in the solution, not gold, and that palladium shows itself with nitric acid.

That is no proof of anything.
What did you use for dissolving the "Stone"?
AR?
How did you use the AR?
Do you know how pregnant Pd looks like in a Stannous test?

Please describe your process in more detail.
If you have pictures it would be nice.

That is no proof of anything.
What did you use for dissolving the "Stone"?
AR?
How did you use the AR?
you know how pregnant Pd looks like in a Stannous test?

Please describe your process in more detail.
If you have pictures it would be nice.

 

[Yggdrasil]

First, I put the stone on the fire for 3 hours so that I could crush it more easily. Then I turned the stone into powder and put the stone powder on the heat for 1 hour so that if there was any sulfur, it would disappear. Then I poured the powder into the mortar. And I added dilute hydrochloric acid to the powder and put it on low heat and then emptied the solution and washed the powder several times. I also did this with dilute sulfuric acid and washed it again. I added ingredients and put it on heat and dissolved the powder in AR./ Here, when I took the stannous chloride test, it was positive, but when I added it to the urea solution and took the test, it was negative./ And I had many questions, why did this happen?!! 》And when I asked the person who was this expert, he told me that you have palladium in the solution, not gold, and that palladium shows itself with nitric acid.

How did the Stannuous look?
How did you make the AR?

 

[Yggdrasil]

First, I put the stone on the fire for 3 hours so that I could crush it more easily. Then I turned the stone into powder and put the stone powder on the heat for 1 hour so that if there was any sulfur, it would disappear. Then I poured the powder into the mortar. And I added dilute hydrochloric acid to the powder and put it on low heat and then emptied the solution and washed the powder several times. I also did this with dilute sulfuric acid and washed it again. I added ingredients and put it on heat and dissolved the powder in AR./ Here, when I took the stannous chloride test, it was positive, but when I added it to the urea solution and took the test, it was negative./ And I had many questions, why did this happen?!! 》And when I asked the person who was this expert, he told me that you have palladium in the solution, not gold, and that palladium shows itself with nitric acid.

Do you have access to DMG?