Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

Michael Bloxham · 2002-04-01 00:33:29

I'll be posting a larger message shortly. Though before I do I want you all to check out the March 2002 edition ('Time Travel. Science Says It Isn't Fiction. But When?' ) of Popular Science. Turn to page 38 and read 'Detergent in the Tank'. Could this new 'Natrium' fuel be the future of space propulsion?
I'll post back on this subject shortly.

Phobos · 2002-04-01 01:32:17

What exactly is special about this fuel? Does it have the power to propel a spacecraft into orbit more efficiently than current fuels? I haven't read the article so I have no idea.

Michael Bloxham · 2002-04-01 13:31:27

Well here goes... I'll be quoting the article, so make sure you all read it. I'm sure most of you subscribe to Popular Science.

To quote the March 2002 edition of Popular Science, 'Detergent In The Tank' pg38:

Commenting on the Chrysler Town & Country Natrium concept vehicle: "...It uses sodium borohydride powder to carry hydrogen in a nonflammable form. To convert that powder to usable fuel, water with sodium borohydride suspended in it is passed over a catalyst made of the chemical element ruthenium. The bonds that hold boron and hydrogen together in this mixture are broken and the atoms are rearranged into sodium borate, and the free hydrogen that powers the vehicle."

So:

Sodium (Na) and Borohydride (BH4) suspended in water (2 parts H2O) are passed through a Ruthenium catalyst. The result is Sodium borate (NaBO2) and freed hydrogen (4 parts H-H).

Now, Basically this 'Natrium' fuel is water. So how can this stuff be used as rocket fuel you ask? Well, It all adds up like this: Imagine filling the Space Shuttles main fuel tank with this 'Natrium' fuel. This fuel is around 3 times more dense with hydrogen than pure hydrogen is when pressurized to space shuttle levels. So it doesn't have to be pressurized. Add a Ruthenium catalyst between the tank and the rocket motor, and Bingo! There is still the need for an oxidizer though. Therefore the 'Natrium' fuel will only replace the hydrogen. The Sodium borate that is left over from the chemical process is discarded.

The main advantages of this new rocket fuel are:

1. It is completely nonflammable. (No more Challenger disasters!)
2. It is a liquid at atmospheric conditions. (Does'nt have to be pressurized)
3. It contains more hydrogen in its liquid form than the most densely compressed hydrogen fuel cell.

So there you have it. Plenty of things still to be worked out though. Remember, this is just a thought. A pondering of my mind. And therefore highly inaccurate. Please do not quote it. Etc. etc.

But even if this is just a pipe theory, I beleive this fuel is the future of all things that go. Turn to page 32 of the same Popular Science issue (March 2002) and read 'Fuel Cells In The Heavens'. If Boeing were to use this 'Natrium' fuel in their little plane there, they would have tripled its range and saved pounds in the process. And then there's the fact that if they crash it, it won't blow up the farm. Because its completely nonflammable. Just think about it for a minute.

Michael Bloxham · 2002-04-02 20:08:35

Speaking of water, Has anyone ever thought of powering an interplanetary spacecraft with the stuff? No seriously. The Mars Direct plan requires a nuclear reactor, right? Well why not use the nuclear reactors power to electrolyze the water? Forgive me if I'm incorrect, but wouldn't the end result (2 parts hydrogen, 1 part oxygen) be ideal for rocket fuel? How much power is required to electrolyze water?

amazingdrx · 2002-04-03 23:08:16

yes water would work that way. for takeoff a microwave laser projected from the ground could be used to electrolize water diresctly into plasma. with extra atmospheric gases used for an energy boost.

once in space solar or nuclear electric power could regenerate fuel from water. extra water can be collected in space.

this is a great transitional design into anti-matter drive. by using solar generated gamma rays to create anti-matter and collecting it in space, future space travel will be solar powered.

Michael Bloxham · 2002-04-04 00:18:42

I don't know what you talking about, Amazingdrx. Powering the electrolyzer with lasers or microwaves, although possible, would be kind of silly. And once in space, I doubt photovoltaics would produce enough power for electrolyzation. And does near-space actually contain water? As for atmospheric gasses providing an energy boost, what kind of gas, exactly?

Michael Bloxham · 2002-04-04 21:40:05

According to Bill White, it is now known that electrolysis can occur through UV light.

Scientific American quote:

"High on a chemist's wish list is a material that uses the sun to split water into its constituent hydrogen and oxygen. Through photosynthesis, plants have no problem performing this action, but humans have had trouble duplicating the feat, which would cheaply produce hydrogen gas, a clean fuel. Today's photocatalysts corrode easily or are too inefficient, functioning only in ultraviolet light, which makes up just 4 percent of sunlight (in contrast, the visible spectrum accounts for 43 percent). Researchers in Japan have found that simply adding nickel to a metal oxide (made from indium and tantalum) yields a stable substance that works in the violet region of visible light. The trick now is to boost the material's conversion efficiency by extending the photocatalyst's sensitivity further into the visible spectrum. The December 6, 2001, Nature describes the results."

Is it therefore possible to power an interplanetary space craft with water electrolyzed with UV light? Perhaps via a large solar concentrator. Thinking a little further... Maybe electrolysis could occur through a fuel cell powered UV light bulb. Have I just invented an engine that runs on water? Will OPEC hunt me down and kill me now?

Adrian · 2002-04-05 03:13:19

The real problem with that is that you have to carry the water around with you, as well as separation and storage equipment for the hydrogen and oxygen; this is why cars that run on hydrogen in the future will not make their own hydrogen from water but will simply load up from hydrogen filling stations.

Also, it might be useful to find out what the specific impulse of hydrogen+oxygen is.

Adrian · 2002-04-05 03:14:56

The real problem with that is that you have to carry the water around with you, as well as separation and storage equipment for the hydrogen and oxygen; this is why cars that run on hydrogen in the future will not make their own hydrogen from water but will simply load up from hydrogen filling stations.

Also, it might be useful to find out what the specific impulse of hydrogen+oxygen is.

Michael Bloxham · 2002-04-05 15:03:15

Current Hydrogen Fuel Cell systems take up much of the floor space of an automobile. The fuel tank alone takes up the whole trunk, weighs 300 pounds (And carries perhaps 30 pounds of hydrogen), and provides the car with about 100 miles range. Water does not have to be pressurized, however, eliminating the need for a heavy pressure tank. Also, a 10 gallon tank of water would provide the fuel cell with enough hydrogen for around 500 miles range. That is, if we were to be using fuel cells at all. BMW has long had 7-Series that burn hydrogen in their internal combustion engines. Converting an internal combustion engine to run on hydrogen is fairly easy, according to BMW. An internal combustion engine is considerably more effecient than a fuel cell as well. But it all doesn't really matter, because electrolyzing water in an automobile would violate the law of conservation. An autombile that runs on water would effectively be a perpetual motion machine. Because the energy needed to electrolyze water is the same as the energy aquired from the oxidation of hydrogen. If we were to electrolyze the water from the suns own UV light, however, we would effectively be building an automobile that runs on UV solar power; Not water. Now we could power an interplanetary space craft in this way, or we could use a UV light bulb, powered by an onboard nuclear reactor, instead. But if we were to do that, than why not just electrolyze the water by conventional electrolysis?

But why even do that? What is the point of using water as fuel instead of just the normal hydrogen-oxygen fuel? Well, I think there are many benifits. One of the most important being the public. The public has always been worried about the flammable nature of hydrogen. If the Hindenburg never blew up as it did, we would probably be traveling the globe in huge hydrogen filled airships (Although I do like to point out that the Hindenburg did not burn because it was filled with hydrogen, but because its exterior fabric was covered with rocket fuel. An Iron-Aluminum powder was used because of its insulating properties, basically the same stuff as the Solid Rocket Boosters on the Shuttle.). An interplanetary spacecaft powered with water would likely appeal to the public, as it is nonflammable. Number two reason is that water is much denser than stored hydrogen/oxygen. Meaning the fuel tanks themselves would not have to be reinforced to such a degree. -A significant weight saving. Number three reason: Simply the fact that it is water. Unused fuel could be stored as extra water for the crew.

So there you have it. So is Natrium fuel the future of space propulsion? Or is water? Well, Natrium fuel basically has all the same properties as water, the upper-hand being that it doesn't have to be electrolyzed to be turned into viable fuel. Rather, it is passed through a small catalyst of Ruthenium. While powering a Launch Vehicle with water would seem ludicrous (As a nuclear reactor would have to be run as it was launched), a Natrium fueled Launch Vehicle would work quite comfortably. And requiring no electrical power in the process. The downside to Natrium fuel: It requires an oxidizer.

Tom Jolly · 2002-05-29 14:48:16

The other downside to Natrium is; given that the H2 density is 4 times as high, the mass per volume is going to be 29 times as high as the H2. So, despite having four times as much hydrogen, you're lifting 29 times the fuel-mass. Or, given the same amount of H2 fuel in both cases, you'll be lifting 29/4 = 7.25 times the fuel mass. Granted, your tank will weigh less, but your catalyst bed will weigh more, so those are probably a toss-up. I doubt that a large rocket could use such a fuel.

Answers to other questions; H2-O2 Isp is about 390. Chamber temp is about 2950 to 3000K. In my chart of various chemical fuels, H2-O2 is nearly the best.

Michael; yes, photovoltaics would work well for electrolysis. Heck, a 9-volt battery can do electrolysis, it's just kind of slow. I've done it with a 15V power supply, too. You can do it easily in your kitchen with just about any power source. Of course, the whole idea of converting power to separate H2 and O2 is kind of silly when you consider that you could take the raw solar power with a parabolic collector and just heat up the water to 3000 degrees and blow it out a nozzle, thus eliminating the gas storage problems and keeping the water handy for other uses (like solar flare shielding, for which water is well suited).

C M Edwards · 2002-05-29 15:55:07

Hello All.

Using electrolysis to split water into hydrogen and oxygen wouldn't produce much thrust at low temperatures, but at very high temperatures this could perform very well. The water could be cracked electrolytically, as in an electrothermal rocket, or using masers and/or lasers. Only electrolysis would work at low temperatures, but at high temperatures (>5000 K) the water will dissociate regardless of the source of heat, so if you're pushing for plasma a maser will work just fine. A VASIMR system would probably run just fine on water.

Natrium (boro-hydrides, magnesium hydrides, whatever) doesn't look like it would be a useful substitute for liquid hydrogen in chemical rockets, because the liquid hydrogen contains more hydrogen per pound. But a plasma rocket is so much more efficient than a chemical rocket that it could make up some of the difference. It needs less fuel, so if there's less hydrogen available per pound then that's just fine.

CME

Canth · 2002-06-02 09:29:53

As far as using a more eisily storable fuel, the next generation reuasable launch vehicle is supposed to use kerosine rather than hydrogen as its fuel. This is mostly because of the higher density of kerosine compared to hydrogen and its non cryogenic nature. Both of these factor allow for a decrease in tank size and weight. Tank bulkieness makes a much bigger difference on a fully reusable vehicle than on a partially reusable one as you have to sheild those tanks for reentry. Natrium used in the way you suggest is especially bad for a fuel because you have to carry the portion of the fuel which isn't hydrogen into orbit with you. This portion of the fuel weighs more than the hydrogen you get out of it. I don't think you could reach orbit at all in the space shuttle by doing what you suggest. Also liquid hydrogen is needed to cool the space shuttle engines and I doubt that the fuel injection system will functuion with a gas rather than a liquid on the space shuttle.

Josh33086 · 2002-06-07 11:13:31

I'm a big supporter of the VASMAIR engines. If it were possible to use water to fuel the plasma rocket it would serve as the best way to go to MARS. The reason is that water has been dicovered on Mars. Even though it is in ice form i'm sure it would not be that hard to heat it and filter it. Taking a page out of Zubrins plan, we could send a probe to mars ahead of time and useing solar power begin to process the water ice. What do you think?

Tom Jolly · 2002-06-09 14:01:02

The difference between the CO2 plan and the Water plan, is, of course, you need to dig the water out using some digging device, one that would have to act autonomously and probably weigh quite a bit, versus a CO2 air pump that weighs next to nothing. I don't think there's much water vapor in the atmosphere, is there?

Tom

Josh33086 · 2002-06-09 15:33:16

Good Point, but would not the plasma rocket be a much faster? As far as processing the water from Mars: Better mapping and such will let us land very near the best water source. Than useing a Pathfinder type rover we could go from place to place processing the water and pipeing it back to the main lander. When we land we will have a network of water pipes.

Shaun Barrett · 2002-06-09 18:45:06

Please excuse my ignorance, but what's a VASMAIR engine? .... In a nutshell.
:0

Josh33086 · 2002-06-10 10:13:34

Plasma Rockets
High exhaust velocity can be achieved by the use of a plasma, where the atoms of the gas have been stripped of some of their electrons, making it a soup of charged particles. The temperature of a plasma starts at about 11,000? C. But present day laboratory plasmas can be a thousand times hotter. Particles in such plasmas move at velocities of 300,000 m/sec. These temperatures are comparable to those in the interior of our Sun. No known material could survive direct contact with such a plasma. Fortunately, a plasma responds well to the presence of electric and magnetic fields. A magnetic channel can be constructed to both heat and guide a plasma, without ever touching material walls. Magnetized plasmas are envisioned to, some day generate abundant energy on Earth, by controlled thermonuclear fusion. Their complex physics is the subject of intense study.

Dr. Franklin Chang-Diaz, NASA

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#1 2002-04-01 00:33:29

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#2 2002-04-01 01:32:17

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#3 2002-04-01 13:31:27

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#4 2002-04-02 20:08:35

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#5 2002-04-03 23:08:16

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#6 2002-04-04 00:18:42

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#7 2002-04-04 21:40:05

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#8 2002-04-05 03:13:19

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#9 2002-04-05 03:14:56

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#10 2002-04-05 15:03:15

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#11 2002-05-29 14:48:16

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#12 2002-05-29 15:55:07

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#13 2002-06-02 09:29:53

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#14 2002-06-07 11:13:31

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

#15 2002-06-09 14:01:02

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#16 2002-06-09 15:33:16

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#17 2002-06-09 18:45:06

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#18 2002-06-10 10:13:34

Re: Chryslers 'Natrium' Fuel - The Future of Space Propulsion?

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