Newsgroup: it.discussioni.misteri
Titolo: Era qui che si parlava di auto ad idrogeno? (In inglese, sorry)

http://www.sciencedaily.com/releases/2007/05/070518163146.htm
New Process Generates Hydrogen From Aluminum Alloy To Run Engines, Fuel 
Cells
Science Daily — A Purdue University engineer has developed a method 
that uses an aluminum alloy to extract hydrogen from water for running 
fuel cells or internal combustion engines, and the technique could be 
used to replace gasoline.
The method makes it unnecessary to store or transport hydrogen - two 
major challenges in creating a hydrogen economy, said Jerry Woodall, a 
distinguished professor of electrical and computer engineering at 
Purdue who invented the process.
Hydrogen is generated spontaneously when water is added to pellets of 
the alloy, which is made of aluminum and a metal called gallium. The 
researchers have shown how hydrogen is produced when water is added to 
a small tank containing the pellets. Hydrogen produced in such a system 
could be fed directly to an engine, such as those on lawn mowers.
[...]
"When water is added to the pellets, the aluminum in the solid alloy 
reacts because it has a strong attraction to the oxygen in the water," 
Woodall said.
This reaction splits the oxygen and hydrogen contained in water, 
releasing hydrogen in the process.
The gallium is critical to the process because it hinders the formation 
of a skin normally created on aluminum's surface after oxidation. This 
skin usually prevents oxygen from reacting with aluminum, acting as a 
barrier. Preventing the skin's formation allows the reaction to 
continue until all of the aluminum is used.
[...]
The waste products are gallium and aluminum oxide, also called alumina. 
Combusting hydrogen in an engine produces only water as waste.
"It's important to note that the gallium doesn't react, so it doesn't 
get used up and can be recycled over and over again. The reason this is 
so important is because gallium is currently a lot more expensive than 
aluminum. Hopefully, if this process is widely adopted, the gallium 
industry will respond by producing large quantities of the low-grade 
gallium required for our process."
In order for the technology to be economically competitive with 
gasoline, however, the cost of recycling aluminum oxide must be 
reduced, he said.
"Right now it costs more than $1 a pound to buy aluminum, and, at that 
price, you can't deliver a product at the equivalent of $3 per gallon 
of gasoline," Woodall said.
saluti,
Peltio
e un generoso excerpt
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 Cells
Va bene. Usiamo un sacco di corrente elettrica per produrre alluminio 
mediante elettrolisi; lo facciamo reagire con l'acqua per produrre 
idrogeno; usiamo l'idrogeno prodotto in una cella a combustibile per 
riottenere corrente elettrica. Ottimo ;-)
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Saluti, VITRIOL

 riottenere corrente elettrica. Ottimo ;-)
Qualcuno lo dica a Grillo e ai suoi sodali...

 corrente elettrica. Ottimo ;-)
Beh, questo è un passo avanti. Prima era l'idrogeno a dover essere 
ottenuto per elettrolisi (con produzione di ossigeno), adesso è 
l'alluminio che viene ottenuto per elettrolisi (con massiccia 
produzione di CO2, LOL, l'ho visto ora 
http://www.world-aluminium.org/production/smelting/chemistry.html
).
Certo è che prodursi l'idrogeno direttamente dall'acqua risolve i 
problemi di trasporto e stoccaggio del gas. Vuoi mettere la figata di 
ricaricarti il portatile con un bicchiere d'acqua?
saluti,
Peltio
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