questions about using sodium formate to drop palladium

[cosmetal]

Well, here is the result... a bit late, and I haven't tested it for purity yet.

The top is how it came out of the crucible. The bottom i polished up a bit to see what kind of shine it would take on. It was tough to get it to buff up, and definitely took a good bit more effort to melt then gold.

Just curious - Did you use any borax during your melt? If yes, did your pickle your button to remove any leftover melting residue (scale/borax?) before you did your XRF?

James

 

[mls26cwru]

Light elements that does not ignite when exposed to oxygen starts at magnesium until calcium. Includes Aluminum, silicon, phosphorus, sulfur, with chlorine and argon as a gas and then potassium and calcium. Below that is beryllium, boron and carbon. Could there have been any of these metals present during the melt?

I really can't think why any would be and especially in that quantity. The crucible started clean and ended with almost no discoloration.

 

[mls26cwru]

Impossible to know without seeing the actual spectra from the xrf read.

Can you get the bead back, or is the deal done?

I have the bead back and will get some pictures tonight... im thinking about trying to melt the bead under vacuum to see if it helps at all.

 

[mls26cwru]

The Ti and light elements might just be slag from the dish. Without seeing the melted button, it's hard for us to describe. I would probably say the XRF is wrong, as torch melting anything with titanium in it inevitably leads to the titanium exiting the stage as TiO2. Lead probably also would've been long gone.


Usually formate Pd is really only contaminated with Ag or other PGMs.

I have been wondering about it... I can understand why traces could be there, but the 93% contamination didn't make much sense. Unless formate drops something like beryllium or barium, but it doesn't seem to be the case from what I have read.

 

[mls26cwru]

Well, here is the result... a bit late, and I haven't tested it for purity yet.

The top is how it came out of the crucible. The bottom i polished up a bit to see what kind of shine it would take on. It was tough to get it to buff up, and definitely took a good bit more effort to melt then gold.

Just curious - Did you use any borax during your melt? If yes, did your pickle your button to remove any leftover melting residue (scale/borax?) before you did your XRF?

James

Yes. I did not have to pickle it though as it was a very clean melt.

To be thorough though, I used and abrasive to polish one side of the button, but then put the button in isopropanol and ran it through an ultra sonic cleaner... then wipped cleaned with methanol afterwords.

 

[mls26cwru]

Oh, I forgot that there is a photo of the button earlier in the thread.

 

[snoman701]

Impossible to know without seeing the actual spectra from the xrf read.

Can you get the bead back, or is the deal done?

I have the bead back and will get some pictures tonight... im thinking about trying to melt the bead under vacuum to see if it helps at all.

have to re-refine it at this point

but i imagine the color of the solution would have been pretty telling

you could also use dmg on an aliquot once you get it in solution.

 

[Geo]

I'm with Lou. I think the XRF was off. The button looks clean. Maybe operator error. Is there any other source for testing it? You may be chasing something that's not there.

 

[rebetulin]

XRF is definitely NOT "deep penetrating" analytical method (something like 10 micrometers). Try to clean the surface of your button, make the XRF measurement again and enjoy result.

 

[zacchy]

At what temperature should the mother liquor solution from platinum be put to precipitate the palladium from these mother liquor with sodium formate?