Sciencemadness Discussion Board

Is Pt on carbon a can of worms I shouldn't open?

SWIM - 13-5-2022 at 21:21

I have only a hazy memory of buying this material. I was on some stuff that paid havoc with my attention span at the time.

Melphalan at about twice the LD50 ( so LD50 + LD50 does not equal LD 100:D, but it ruins your mind for months.)

Anyway, what I have is platinum 5% on carbon. lots of it.
The bottle is still sealed, but I did open the foil package the sealed bottle was sealed in. It was an Aldrich product. Pretty sure it was a real steal or or wouldn't have bought it. It also looks pretty old.

About all I know about using this stuff is that it can be used for many reductions at fairly low pressure, and that it tends to catch fire and ignite things. And the bottle has a warning to "store under nitrogen!"

I do have Schlenk flasks, and am planning to get a nitrogen tank anyway for other uses.
Please understand that I'm not asking what I can do with it. I know it has many interesting uses and that I will probably have as good a time researching them as I will doing them.

What I'm asking is if The hazards aren't worth the risk given that there are so many other reduction schemes out there nowadays.

Yes, I will be researching proper practices for this stuff. (unlike the embarrassing LAH practices I recently admitted to)

But is it likely that I'd be better off trading it for some other reducing agents If I find somebody who really needs this specifically? And maybe even has a Parr bottle and shaker, which I don't. I do have some ace thread vessels that should be good for moderate pressures.

I am also somewhat attracted by the idea of doing reductions old-school style so there is that too.

It's 100 grams so I figure it'll last a damn long time if I do keep it.

So, basically, is messing with this dumber, or even just more pointless, than it sounds?
(Given the availability of modern alternatives)

[Edited on 14-5-2022 by SWIM]

[Edited on 14-5-2022 by SWIM]

Texium - 14-5-2022 at 07:29

Well, I haven’t personally used it (though I also own a couple small jars of it), but my understanding is that the only time the material becomes dangerously pyrophoric is when you’re trying to filter it post-reaction. The catalyst at that point is saturated with hydrogen, and wetted with flammable solvent, and if you pull air through that, you’re asking for trouble. I don’t know this from personal experience, but one of my professors described this happening to him a few times.

While fact checking myself, I came across a paper that goes into detail on safely filtering palladium on carbon. I couldn’t find any specific info about platinum on carbon from a cursory search, but they’re very similar so it should still apply.

Attachment: acs.oprd.1c00190.pdf (420kB)
This file has been downloaded 185 times

SWIM - 14-5-2022 at 09:13

Thanks!

Fantasma4500 - 15-5-2022 at 02:55

this could.. potentially be used to make alcohols into aldehydes? one can construct a device where a redhot glowing copper wire is put into ethanol vapors and air is pumped into it and then pump the formed acetaldehyde further about
silver works more effectively and barely needs to be heated- i'd assume platinum on carbon is the same deal
and ... could this maybe work by simply bubbling air onto the platinized carbon in suspension? otherwise putting some of it in a glass tube so ethanol passes over it along with air should work

Texium - 15-5-2022 at 07:45

Bubbling air into the catalyst suspension might work. I’m going to see if I can find a paper on that. Passing the hot vapors and air over the catalyst is more likely to just start a fire.

Fantasma4500 - 16-5-2022 at 02:34

especially methanol oxidation is prone to ignition- i believe one could just manipulate the airflow to regulate reaction speed