Sciencemadness Discussion Board

platinum on kaowool

Jor - 23-4-2010 at 11:42

I have obtained 5g of 5% Pt on 'Triton Kaowool' from BDH.
Apart from some specialist applications I do not really know what to do with this. It can decompose hydrogen peroxide, that's one thing I have read.

Does anyone of you know some nice applications? If not I might just extract the Pt from it.

Together with this I also obtained 100mL 2% HAuCl4.3H2O solution and 60mL 12g/L chloroplatinic acid, quite interesting :P

DJF90 - 23-4-2010 at 12:42

Platinum on kaowool can be used as catalyst for oxidation of SO2 to SO3 and also to catalyse the direct union of the elements hydrogen and iodine (and possible H and Br too) forming HI (and HBr respectively).

Picric-A - 23-4-2010 at 14:12

Pt is a very poor catalyst for SO2-->SO3, it is very easily poisoned by other sulphur compounds in the SO2 and rendered useless untiil re-activation.

It is good, however, for the oxidation of NH3 --> NO --> NO2!

Jor - 23-4-2010 at 14:18

I am not really interested in making the acid oxides NO2 and SO3 although it is interesting that this material might catalyse the formation of these compounds.
I might give the reaction of hydrogen and iodine a try, quite an interesting reaction. And maybe hydrogen and bromine, although this reaction may be somewhat violent I think :o

What would be the most practical way of doing this? Does it only work in the vapour phase, or can I lead a stream of hydrogen over the iodine mixed with some of the catalyst. I know this might be wasteful, but hydrogen is very cheap so that's not a problem.
I migth give this a try sunday.

In any case, it seems like this is a useful catalyst and not worth destroying by extracting 250mg Pt metal from it.

Picric-A - 24-4-2010 at 01:18

It would have to be in vapour phase at around 300deg c. best thing to do is pass H2 through mildly heated I2 in a flask which would give you a mix of H2 and I2, pass this over the cat then condense out remainding I2.

Vogel has a good diagram of the ideal apparatus for this i think.

[Edited on 24-4-2010 by Picric-A]

DJF90 - 24-4-2010 at 06:03

The procedure is in Brauer (Vogel is ORGANIC chemistry) and both use a "similar" apparatus. I suspect you can use your catalyst in most places where Pt/SiO2 is used, and maybe even as a substituent for Pt/C. Seeing as you're going through the trouble to make anhydrous hydrogen halides, best to absorb them in a non-aqeous, non-reactive solvent in which they can be put to further use. Something like GAA would be appropriate for HBr, not sure what's common for HI though.