Extracting energy out of hydrogen and oxygen

[Lok]

Hydrogen and natural gas flame temperatures are very similar.

This usually explains why steel (not pig iron) took so much time to be truly molten. It melts at about 1500 plus give Celsius.From a historical point of view where natural gas was very abundant. No.

 

[mheslep]

... It melts at about 1500 plus give Celsius.From a historical point of view where natural gas was very abundant. No.

Yes. There's a lot of engineering in the heat management of gas turbine engines. Heat resistant metals or ceramics are used, and the combustion gasses are rapidly expanded which cools them.
http://www.energymanagertraining.com/power_plants/Gas_Turbines.htm
http://www.netl.doe.gov/technologies/coalpower/turbines/refshelf/igcc-h2-sygas/Using%20H2%20as%20a%20GT%20Fuel.pdf

 

[Topher925]

Fuel cells do not require pure hidrogen, not that pure hydrogen is that hard to get. Engines are actually more fussy about purity, I mean a constant purity that it is set.

This is incorrect. Fuel cells are very easily poisoned by CO and H₂S. CO and sulfur based impurities bond with the platinum on the anode side of the cell removing reactions sites for the hydrogen. CO can be easily removed by applying a potential across the cell but sulfur based compounds have stronger bonds and sulfur sticks to just about everything so removing it can be more difficult.

Often, bi-metal catalysts are used on the anode side of a fuel cell to help reduce the effects of poisoning. Pt-Ru is a very common catalyst but the added Ru makes it more expensive.

Heat resistant metals or ceramics are used

Do they actually use ceramics commercially in heat turbines these days? I thought the failure rate of ceramics was still to unpredictable.

 

[mheslep]

Do they actually use ceramics commercially in heat turbines these days? I thought the failure rate of ceramics was still to unpredictable.

I can't reference a model number, only this at the moment:
http://www.energymanagertraining.com/power_plants/Gas_Turbines.htm