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US Navy Tries To Turn Seawater Into Jet Fuel
Hugh Pickens writes "New Scientist reports that, faced with global warming and potential oil shortages, the US Navy is experimenting with making jet fuel from seawater by processing seawater into unsaturated short-chain hydrocarbons that with further refining could be made into kerosene-based jet fuel. The process involves extracting carbon dioxide dissolved in the water and combining it with hydrogen — obtained by splitting water molecules using electricity — to make a hydrocarbon fuel, a variant of a chemical reaction called the Fischer-Tropsch process, which is used commercially to produce a gasoline-like hydrocarbon fuel from syngas, a mixture of carbon monoxide and hydrogen often derived from coal. The Navy team have been experimenting to find out how to steer the CO2-producing process away from producing unwanted methane by finding a different catalyst than the usual one based on cobalt. 'The idea of using CO2 as a carbon source is appealing,' says Philip Jessop, a chemist at Queen's University adding that to make a jet fuel that is properly 'green,' the energy-intensive electrolysis that produces the hydrogen will need to use a carbon-neutral energy source; and the complex multi-step process will always consume significantly more energy than the fuel it produces could yield. 'It's a lot more complicated than it at first looks.'"
...they could just hire Jesus.
But it's easy to put a nuclear reactor in a ship, and not so easy to put one in a fighter jet.
Brett
Nuclear powered aircraft carrier, so you've got a pretty good supply of energy there, being able to convert electricity into jet fuel would save them money and reduce the amount of fuel they have to carry (reducing the amount of flammable liquids held in a ship that might get hit by a missile), and could end the need to resupply fuel, all in all very sexy if you're going in to combat.
oceans absorb CO2
CO2 + H20 H2CO3
H2CO3 ==> HC03- + H+ with a pKa of 3.6
This means that we will eventually turn the oceans into Coca Cola. Not too good for the flora and fauna, I can imagine. There's a practical limit to the CO2 that the oceans can absorb.
Of course if we could create some sort of genetically engineered algae that happened to produce carbonic anhydrase, you'd be able to degas huge amounts of ocean water just by pouring it into your algae tank...
Seven puppies were harmed during the making of this post.
Exactly, it removes one of the biggest and most vulnerable pieces of the supply chain to a carrier group, fuelers for the aircraft. If this becomes a reality soon I think good old CVN-65 (Enterprise) may get a reprieve from retirement. There's nothing quite like the spare capacity in those 8 reactors to power something like this =)
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
There's a practical limit to the CO2 that the oceans can absorb.
I think the point being made above is that if we're sucking the CO2 out of the ocean in the first place, it'll make a buffer to absorb what we've extracted. Or to use an analogy, we're emptying the carbon sink on the one hand and topping it up with the other, hopefully leaving things even.
Man who leaps off cliff jumps to conclusion.
This has got nothing to do with creating free energy, and it's got nothing to do with environmentalism. It's all about military strategy.
Your nuclear-powered carrier fleet is on patrol in a war zone. Resupply convoys are a risky business. How do you keep your planes in the air without a constant supply of jet fuel?
You make your own on board. Who cares if it's "thermodynamically a huge waste"? You've got a freaking NUCLEAR REACTOR. It's got plenty of energy to spare, all you gotta do is repackage that energy into a form that can be poured into an aircraft fuel tank.
I mean, forget about all the CO2 produced when vast amounts of energy are expended to obtain, store, ship, and heat all that non-naturally occurring hydrogen - you don't need to know about THAT CO2
Indeed. You don't need to know about it because it doesn't exist. The energy source is nuclear, not carbon based. If you didn't know that the US has nuclear powered ships, then you are clearly not a geek. Please hand in you card on the way out.
SJW n. One who posts facts.
So it may actually be more efficient thermodynamically.
Deleted
You mean, like maybe the Navy might find a way of turning seawater into jet fuel?
If the masses can keep you down, you're not the Ubermensch.
Wind power has lots of advantages, but one major drawback - it is intermittent. If you have an industry which is very energy intensive but has low capital cost, this presents an opportunity: build your plant, and run it only when the wind is blowing and power is very cheap. This works especially well if your product is easily storable.
This process is clearly energy intensive and produces an easily storable product - whether it has the required low capital cost is much less clear. (Although the interest of the navy suggests they're wanting to use aircraft carrier nuclear power, but once developed it could find wind-powered civilian use.)
Water desalination and aluminium smelting might also qualify (I don't know the capital costs of these). Recharging electric cars certainly does (given that you're buying the car anyhow), except that you have a very limited storage capacity.
Despite not being low capital, data centres are even starting to go this way, being built with the intention of only running them when electricity is cheap (or less is required for air conditioning.) In this case the product is extremely transportable rather than easily storable.
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