Haber process alternative catalysts

[Chap]

Iron is probably the only catalyst used in the Haber process, today. Why aren't any other transition metal catalysts used for this process? osmium and ruthenium aren't economically feasible, but what about other transition metal elements such as Nickel or Copper? Is there a specific reason why Iron is the most suitable catalyst for this process or is iron the cheapest substance that can be used for this process?

 

Another fact to consider is; Iron is one of the chief components in nitrogenases, the group of enzymes used by particular biological organisms to convert dinitrogen into ammonia. Is it probable that the biological organisms use iron in their enzymes because evolution has proved it to be the one of the most efficient catalysts compared to other transition metal elements?

 

I would like to know your views.

Thanks.

 

 

 

[John Cuthber]

They tried the other metals and iron works best.

The cost of a catalyst isn't much of an issue since it's reused.

They do use platinum for some things like nitric acid production.

[Xittenn]

I did a fair bit of research into this when it was posted. Nitrogenase alternatives are being researched as alternatives, but as for a direct correlation it is quite the opposite. Iron catalysts overcome the activation energy that nitrogenase enzymes would otherwise have reduced, under extreme temperature and pressure. Ru is being used in stages, where it is preferred to poison the Iron catalyst the early stages of synthesis, and where they can then take advantage Ru in later stages. There are a number of newly emerging alternatives that are being used in a variety of stages such as the A301 Catalyst.

 

 

interesting stats presentation:

 

[Chap]

Thank you for your replies!