# palladium hydride ?



## samuel-a (Jun 2, 2014)

All,

I have what i suspect is Pd powder which contains significant amounts of H.
The powder is dry and includes a small carbon contamination (a rough estimate would be 0.5-3% W:W).

Heating the powder causes violant eruptions which shoots powder and sparkes all over the place.
I'm trying to treat the material and bring it to simple Pd powder but avoiding chemically leaching the Pd or thermaly "decompose" it.

Any ideas?


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## Lou (Jun 2, 2014)

Pd really likes hydrogen and always does this. In short, if you don't have a tube furnace, vacuum pump, and Ar or CO2, you're up the creek on this one.


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## samuel-a (Jun 2, 2014)

Dear Lou,

I had feeling you will say that.
I really wished to avoid dissolving 3lb of Pd, only to cement back with Fe or Zn.


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## artart47 (Jun 2, 2014)

Hi !
I don't know what kind of temp it must be heated to, but the idea that popped into my head was like a coffee pot sitting on a large dish withan inverted beaker over the top also sitting on the dish. if the dish is heated and the PdH starts poppin ,any powder that gets blown out would fall on the dish and be recovered. 
have to gard against hydrogen explosion.
Hope that helped!
artart47


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## solar_plasma (Jun 3, 2014)

Wouldn't the hydrogen be removed, if you used the Pd in a hydrogenation process? I just read about it, but maybe you can find something that will work for you...


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## solar_plasma (Jun 3, 2014)

As a matter of fact, palladium is not forming any hydrides, but the hydrogen atoms are stored in octamer or -tetrahedron holes. My thought was to use the H-containing powder for a hydrogenation like in the production of margarine. Since this is only something I read here and there a little about, I have no clue, if this could work for an elimination of hydrogen from your powders. This should be easy to answer for the chemists.


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## Lou (Jun 3, 2014)

Sam,

Why don't you dissolve it in 6 M HCl w/ peroxide, boil, filter, concentrate and dissolve in ammonia, then actually refine it.

The yellow powder reduces nicely in pH 6 sodium formate at about 80*C.

Alternatively, 

You could oxidize all the carbon (and any hydrogen) away and turn it to PdO in air at 550C, then heat that at about 750-800 *C under high quality carbon dioxide.


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## samuel-a (Jun 3, 2014)

Lou,

These 3lb came in as part of a larger lot (though seperated) which i actually do burn to eliminate carbon.
The problem with these spcific 3lb is that it react with heat very badly. However, refining it is really not worth my while. I only do the pre-treatment to reduce volume and eliminate nasty chemicals.
As for the actuall refining... Metalor.


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## Lou (Jun 3, 2014)

Ah.

So you're just trying to make it safe to ship?

Heat it under a vacuum at 200*C and that'll help.


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