[Stoves] Hydrogen from water increasing heat

[AJH]

On Fri, 7 Dec 2007 22:50:44 -0800, frank at compostlab.com wrote:

>Not sure what that will tell us but i think if the flame is cooler with the
>water means heat is removed as steam but if the temp is higher it means that
>water does split and hydrogen aids combustion.

I'm unsure from your description what's supposed to be happening but
vaporising water will be endothermic as will be splitting water into
hydrogen and oxygen, if they did split they would have to recombine
unless another chemical process intervened and carried of the hydrogen
and oxygen atoms in other molecules. In recombining they would give
off the same energy that was absorbed in splitting, so no net effect.

> Perhaps it only splits at the
>higher nitrous oxide and acetylene flame and not at the lower temperatures of
>air acetylene or even the lower temperatures we are working with. Knowing the
>temp that it does split (if it does) could greatly help us optimize the moisture. 

In the absence of a catalyst I think steam will start dissociating at
1800K at low pressure and a quick google suggests that this process
will only complete under a high vacuum and 3600K.

It's all largely academic as I don't believe temperatures of >1200C
(~1500K) are attainable in these small stoves.

AJH