What effect does temperature have on electrolysis of an aqueous solution?

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Offline peppercorn

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If hydrogen is produced by electrolysis, is the process efficiency increased for an elevated solution temperature?

Thanks.
« Last Edit: 25/10/2008 12:32:52 by chris »

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Offline RD

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High temperature electrolysis is more efficient economically than traditional room-temperature electrolysis because some of the energy is supplied as heat, which is cheaper than electricity, and because the electrolysis reaction is more efficient at higher temperatures.
http://en.wikipedia.org/wiki/High-temperature_electrolysis

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Offline peppercorn

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Thanks RD,

An interesting article.

I had some thoughts similar to those which the article alludes to - namely using a heat engine in conjunction with a electrolyser.  The upper temp of 850degC which is mentioned is certainly in the ball-park of diesel exhaust gas temp.

However, the idea of gaining enough efficiency advantage for electrically splitting water at these temps to feed the engine is clearly against thermodynamic laws.

The only way I could see this process being advantageous is where the hydrogen generated could be used to 'upgrade' a lesser fuel source - like biomass.

???