New fuel for 21st century -- aluminum pellets? - Reuters

[Eugene]

Source: Reuters

New fuel for 21st century -- aluminum pellets?

By Julie Steenhuysen
1 hour, 53 minutes ago

CHICAGO (Reuters) - Pellets made out of aluminum and gallium can produce
pure hydrogen when water is poured on them, offering a possible alternative
to gasoline-powered engines, U.S. scientists say.

Hydrogen is seen as the ultimate in clean fuels, especially for powering cars,
because it emits only water when burned. U.S. President George W. Bush has
proclaimed hydrogen to be the fuel of the future, but researchers have not yet
found the most efficient way to produce and store hydrogen.

The metal compound pellets may offer a way, said Jerry Woodall, an engineering
professor at Purdue University in Indiana who invented the system.

-snip-

For now, the Purdue scientists think the system could be used for smaller
engines like lawn mowers and chain saws. But they think it would work for cars
and trucks as well, either as a replacement for gasoline or as a means of
powering hydrogen fuel cells.

-snip-

Read more: http://news.yahoo.com/s/nm/20070518/sc_nm/fuel_hydrogen_dc

[jpak]

1. Wow - pretty amazing if these claims pan out

I wonder what the yield of hydrogen per gram (or kg) is...and a net energy analysis would be good thing too.

[youngdem]

2. Are gallium and aluminum anywhere near as plentiful as we would need for this to work?

[slackmaster]

3. Probably, but the problem is it takes lots of electrical power to refine aluminum

As I understand this, the gallium does not get used up. It's kind of expensive.

[jpak]

6. Aluminum is one of the most abundant elements in the Earth's crust

and most Al is currently smelted using renewable electricity (hydroelectric or geothermal).

Both the gallium and aluminum can be recycled, but you would need electricity to reduce the oxidized Al back to the usable alloy.

[sam sarrha]

4. * is rrefering to hydrogen produced from Coal.. Google:Coal Mountain Topping

[eppur_se_muova]

5. Just another way of storing and moving energy, not a new source.

The ONLY reason aluminum is cheap is that it is recycled and remelted; without this, the price of aluminum would be about 10x higher. Using Al as a fuel like this would be a one-pass, no recycle, use, which would drive the price of Al up. The only energy which comes out of the Al (whether as H2 or electricity) is the energy which was put into it to reduce aluminum ore (Al2O3) to Al.

Others have already suggested (and probably patented) the use of solid Al as a fuel to propel a car via a fuel cell; the idea of using Al as a source of H2 (with the addition of strong base, not neutral water, as in the OP) has also been around a long time, with all the disadvantages already noted, plus the hazard of handling corrosive alkali.

[skids]

7. Why not just a direct metal fuel cell?

Why the H2 step?

[eppur_se_muova]

8. Maybe because the metal fuel cell has already been done ? ...

http://www.freepatentsonline.com/4275125.html

Basically just a battery with a replacable anode. You're right, it should be more efficient, and easier to turn on/off than if H2 is generated in an intermediate step. But see my comments in the previous post re cost.

The guy has half an idea, doesn't see the faults, and thinks it's a revolution.