Catalysts:- Wood burns when the catalyst- heat is applied in the
presence of oxygen,resulting in compounds CO2,CO, etc, and more heat.
Can you substitute  this catalyst with another.In other words, why
does wood need heat to complete the chemical reaction of burning? What
if you used something the allowed the same reaction, but did not need
the catalyst -heat? Could you apply this logic (if the former was
possible) to the Haber process of producing Anhydrous Ammonia, where
you could maybe find a catalyst to take the place of "pressure", and
maybe "heat",  so you could make the reaction work under more
favorable, less hostile working environments?.

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Request for Question Clarification by kyrie26-ga on 14 Jun 2003 20:50 PDT

Hi redbaron007-ga,

Are you looking for only an answer that provides a definite "yes" for
a replacement catalyst in these reactions, or are you looking for an
exhaustive explanation regardless of whether the answer is yes or no?
In other words, will you accept as an answer "there is no replacement
because..."?

Thanks,

kyrie26-ga

Hello -

The traditional Haber process, as you noted requires very high
temperatures (400 degrees) and pressures (200 atmospheres) using the
traditional iron catalyst (iron oxide).
A nice description of the tradional Haber process:
http://www.chemguide.co.uk/physical/equilibria/haber.html#top

A supplier of traditional catalysts (with a nice description of the
process):
http://216.239.57.100/search?q=cache:tiPPy_Pb36kJ:www.synetix.com/ammonia/pdfs/216w.pdf+%22ammonia+synthesis%22+catalyst&hl=en&ie=UTF-8

A catalyst billed as a low-temp, low-pressure catalyst (although the
temp appears to be only slightly lower):
http://216.239.57.100/search?q=cache:Uvn60TwFg9MJ:www.americanlb.com/a301.html+%22ammonia+synthesis%22+catalyst&hl=en&ie=UTF-8

Osmium and uranium are also possible catalysts in this reaction:
http://www.wikipedia.org/wiki/Haber_process

Another recent paper describing a molybdenum-cobalt catalyst that
allows synthesis at 500 degrees and around 70 atmospheres:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11516293&dopt=Abstract
http://pubs.acs.org/cgi-bin/article.cgi/jacsat/2001/123/i34/pdf/ja010963d.pdf

A nice description of the process, it's history, and the industrial
processes, as well as a description of a ruthenium on activated
graphite catalyst (same temp, but only 80 atmospheres of pressure):
http://www.ias.ac.in/resonance/Sept2002/pdf/Sept2002p69-77.pdf

More recently, it has been reported that ammonia formation can be
acheived with ruthenium catalysts at 55 degrees and 1 atmosphere
(really mild conditions).
Hidai et al, Science 23 January 1998 Volume 279 Number 5350

A very low yield example, at 70 degrees in water under atmospheric
pressure:
http://pubs.acs.org/cen/topstory/8114/8114notw7.html

Another recent paper describing a molybdenum-cobalt catalyst that
allows synthesis at 500 degrees and around 70 atmospheres:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11516293&dopt=Abstract
http://pubs.acs.org/cgi-bin/article.cgi/jacsat/2001/123/i34/pdf/ja010963d.pdf


These are the only avenues which I could find for catalyst manufacture
- let me know if you want any more information about them.

synarchy

Search strategy:
"ammonia synthesis" catalysts
"haber process" catalysts
ammonia catalysts
"low temperature" haber
"low temperature" "ammonia synthesis"
"low pressure" haber
"low pressure" "ammonia synthesis"
low-temperature haber
low-pressure haber
low-temperature "ammonia synthesis"
low-pressure "ammonia synthesis"

good info, but I need followup