Pd Pt Rh mix industrial cat refining tips ?

[Mdctr]

Since NH4Cl melts at 338C that is not

What would be the intention of such melting and addition ? I don´t understand.
Molten sodium chlorate is insanely dangerous oxidant. And ammonium chloride rather sublime than melt.

 

[Mdctr]

Quicker precipitation

 

[Yggdrasil]

Quicker precipitation

It can not be done, if you pour molten Sodium Chlorate at 300+ C into a liquid at say 50C you will have a steam explosion throwing seering hot intense oxidiser all around you.

How do you come up with such Ideas?

Are you sure you don’t mean dissolved and not molten?

 

[Allthatscrap]

To your solution, add a concentrated solution of ammonium chloride. Amounts and volumes are relative. Add the concentrated solution to the pregnant solution in amounts that are relative to the starting amount of pregnant solution. The ammonium chloride does two important things. First it drops Pt as a yellow salt. This is what you are looking for. Add until no more yellow salt is produced. Second, the ammonium binds with the palladium chloride. This allows the Pd salt to be converted to a solid by adding chlorine gas. The Pd salt will precipitate as a red to dull-red salt. None of this effects the rhodium to any great degree, which remains in the solution. I recover the Rh and can clean it somewhat but have never tried to refine Rh. Be aware that finely divided Rh powder will dissolve in concentrated HCl without an oxidizer. Palladium is difficult to cement from acidic solutions. It tends to dissolve in dilute HCl. To successfully cement all Pd from an acidic solution, the PH must be adjusted up. From my own observations, the less reactive a metal is, the harder it is to drop as an oxide. You can dilute gold solution until the solution has no color but still test positive for gold. All of the less reactive metals exhibit the same behavior. In an electrowinning cell, the solution entering the cell has very little dissolved metal initially.

Hey there geo,
Is this that's so you are still in this forum?


I've appreciated your previous post, slot, I just wanted to see if I could pick your brain a bit aboutPd and it's yellow salt ammonium chloride and which way from there one might choose to go fourth with. Is rendering the red salt a complete action?

 

[Yggdrasil]

Hey there geo,
Is this that's so you are still in this forum?


I've appreciated your previous post, slot, I just wanted to see if I could pick your brain a bit aboutPd and it's yellow salt ammonium chloride and which way from there one might choose to go fourth with. Is rendering the red salt a complete action?

I think you should hurry slowly.
Dealing with Gold and Silver is hard enough until you master it.
Dealing with Platinum Group Metals are waay harder and a lot more toxic.
Get confident with Gold and Silver first.

 

[Geo]

I agree with Yggdrasil. Master one thing at a time. The knowledge you gain from studying one element at a time will help you with the next.

The yellow salt of Pd is obtained by a different method. Ammonium hydroxide is added to palladium chloride solution until the solution has been neutralized. Then an excess of ammonia is added to the pink/flesh colored Pd salt until the salt goes clear of color. Then small additions of HCl will precipitate the yellow salt of diammine-palladium (II)chloride.