axehandle - 30-12-2003 at 19:20
I'm trying to set up a small sulfuric acid
production system, but am unable to
find any company willing to sell V2O5
to an individual (only to other companies).
Does any catalyst whiz know if I could
substitute dicobalt trioxide
for the V2O5? The former I can buy very
cheaply from a ceramics supplier, the latter
they have discontinued selling. Bastards.
I'd hate to have to buy that $200 piece
of platinum/rhodium wire I got a quote for
after finally managing to find a company
willing to sell noble metals to individuals.
Also, a metal oxide would be 10^5 times
as easy to layer on top of ceramic
substrates than it would be to weave an
extremely fine gauze by hand.... and no,
obtaining a used car cat is impossible here.
Mumbles - 31-12-2003 at 09:19
Hmmmmm, I think someone needs to look a little harder. And I think someone needs a new ceramic supplier. A nice quick googling, I found at least 10
different ceramic suppliers, in multiple countries, that sold it. They also sold it at quite a reasonable price. Cheaper than most of the Co2O3 I
saw. Its not even that hard to find the metal wires you speak of. It will be expensive though.
As for the actual question about Co2O3 as a catalyst for Sulfuric production. There is a possibility, but I have serious doubts about it. Someone
else can probably provide some resource for why, but I just don't know exactly. My best guess would that it wouldn't lower the activation
energy enough, for the extra oxygen to bond. It just doesn't seem like it would work.
KABOOOM(pyrojustforfun) - 31-12-2003 at 13:42
what cheaper than Fe<sub>2</sub>O<sub>3</sub>? best T is 620°C (
) with a yield of 75% (from an industrial inorganic chemistry book)
Organikum - 31-12-2003 at 14:00
You get an brandnew replacement catalytic converter for about 60Dollar in the US and for about 100Eu in Europe.
And I hope you know that neither vanadiumpentoxide nor manganesedioxide or this cobaltoxide you spoke of can be used successfully "as is" in
catalytic processes. You need the nitrate or sulfate for example or the carbonate to precipitate the oxide in an active form on the surface where it
has to get reduced by passing hydrogen over the heated catalyst and reoxidized by passing air over it. (there are different ways possible - this is a
general description of an activation process which works basically always).
My personal advice would be to use Fe2O3 (precipitated from the sulfate for example - most easy) as KABOOM told and to do a really good precipitation
and activation job on this catalyst.
[Edited on 31-12-2003 by Organikum]
axehandle - 1-1-2004 at 18:42
"You need the nitrate or sulfate for example or the carbonate to precipitate the oxide in an active form on the surface where it has to get
reduced by passing hydrogen over the heated catalyst and reoxidized by passing air over it. (there are different ways possible - this is a general
description of an activation process which works basically always)."
Is this really necessary with Fe2O3? The
result would be no different from a very finely divided powder stuck on ceramic pellets, I would think. Or am I missing something here? I'm not
trying to take a PhD in chemistry, I'm just trying to make some sulfuric acid.... I don't even not what
"diatomeous earth" is (sp?).
A google search on "catalyst activation" +
Fe2O3 gave only some PDF docs on a level far above my understanding.
I think I'll stick with plain old
platinum/rhodium gauze.