Navy lab makes gasoline from seawater, as low as $3 per gallon

[eridani]

Still thinki that the energy input costs are prohibitive, but it would be great if they came down.

http://www.dailykos.com/story/2014/04/07/1290380/-Navy-lab-makes-gasoline-from-seawater-as-low-as-3-per-gallon

The U.S. Naval Research Laboratory (NRL) announced today that they have manufactured long-chain hydrocarbons -- that is essentially gasoline -- entirely from seawater, and used the fuel to power a flying model aircraft.

Using a patented electrochemical process, they have simultaneously extracted dissolved CO2 ions and created hydrogen gas from seawater. The resulting mixture of gases is then reformed into long-chain hydrocarbons in a chemical reaction.

One big caveat: obviously, there is no free lunch, and this process requires energy as input. But since it is entirely feasible to use non-fossil energy sources to power the process, the fuel created could be essentially fossil-free (carbon neutral) gasoline. The oceans and atmosphere exchange CO2 readily in massive quantities, so taking it from one place is functionally the same as taking it from the other.

The NRL press release contains this interesting quote:

Using an innovative and proprietary NRL electrolytic cation exchange module (E-CEM), both dissolved and bound CO2 are removed from seawater at 92 percent efficiency by re-equilibrating carbonate and bicarbonate to CO2 and simultaneously producing H2.

Note that they're not specifically claiming the H2 was electrolyzed by splitting water. That's because the bicarbonate ion is formed when a CO2 molecule combines with a OH- (hydroxyl) ion, forming the bicarbonate ion HCO3-. So there is at least the theoretical possibility that the NRL process might run something like this:

2(HCO3-) --> 2(CO2) + H2 + O2 + 2(e-)

[PoliticAverse]

1. Prior DU discussion with several links with more info here:

http://www.democraticunderground.com/1014774527

[Demeter]

2. I suppose they are using seawater from the Gulf of Mexico

and Prince William Sound, Alaska, site of the Exxon Valdez contretemps?

Hell, I could make gasoline out of that!

[eridani]

4. No--they're making it out of bicarbonate ions

The net energy balance is still questionable, though.

[Demeter]

5. I was being sarcastic, sorry

[eppur_se_muova]

3. BREAKING: Military meets projected cost estimates ...

$3/gal my ass !