> I am still wondering where the energy will come from to heat the sugar?

Sucrose (and several other sugars) is C12H22O11
In combustion of sugar the end products are water and CO2

You can think of this being 11 x H2O + 12 x C
or 22H + incomplete CO2 needing extra Oxygen.
Energetic concerns and structure (crudely put) govern what actually happens.

From the above you can see that the claim in the web page cited
http://europe.cnn.com/2002/TECH/science/08/28/sugar.cars.reut/index.html
is, at best,  incomplete as more Oxygen is need to make CO2
viz

"The research, to be published Thursday in the science journal Nature, found
that heating the sugar solution to 392 degrees Fahrenheit and passing it
over a platinum-based catalyst broke it down into hydrogen and carbon
dioxide."

[[392F = 200C]]
 It requires more Oxygen to get CO2 plus Hydrogen.
The conversion described is probably catalytic with respect to the Platinum
and probably adds Oxygen with a net energy output to drive the process. The
overall result is probably LESS energy from the Hydrogen combustion than
from Sugar combustion BUT having pure Hydrogen is useful. I haven't heard of
a fuel cell that runs on sugar yet :-).

The conversion process can probably provide process heat for some other
activity.

Sugar makes a respectable rocket fuel but is not as "good" (energetic) as
the pure Hydrocarbon "rubbers" in use in rocket fuels (eg PBAN in the Space
Shuttle boosters or the slightly superior HTPB which is similar to the
rubber in car tyres.).

The "probably" watchdog is going to bite me if he reads all the foregoing
:-)


            Russell McMahon.


> ----- Original Message -----
> From: Jim Korman <jkorman@ALLTEL.NET>
> To: <PICLIST@MITVMA.MIT.EDU>
> Sent: Thursday, August 29, 2002 8:42 PM
> Subject: Re: [OT]: Hydrogen from sugar
>
>
> > Peter L. Peres wrote:
> >
> > > http://www.cnn.com/2002/TECH/science/08/28/sugar.cars.reut/index.html
> > >
> > > --
> > > http://www.piclist.com hint: To leave the PICList
> > > mailto:piclist-unsubscribe-request@mitvma.mit.edu
> >
> > Begs the question,
> >  If x amount of sugar can produce y amount of energy ,
> > how much energy z did it take to produce and refine the sugar?
> >
> > Jim
> >
> > --
> > http://www.piclist.com hint: To leave the PICList
> > mailto:piclist-unsubscribe-request@mitvma.mit.edu
> >
> >
>
> --
> http://www.piclist.com hint: To leave the PICList
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>
>

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