Hydrogen leakage

[gutharius]

Is it possible to contain a large amount of hydrogen in a container and keep even the smallest amount from leaking?

I have read, "Because hydrogen is the simplest element, it will leak from any container, no mater how strong and well insulated, at a rate of at least 1.7 percent per day." Is this correct???

 

[Dubb]

http://www.ovonic.com/sol_srv/...n_sol/hydrogen_sol.htm

"Today, Texaco Ovonic Hydrogen Systems offers an innovative storage tank and canister technology that uses breakthrough metal hydride technology to store and distribute ultra-clean hydrogen fuel in a stable, solid form. The solid hydrogen storage system is the safer, lower-pressure alternative to compressed-gas and liquid hydrogen storage. The hydrogen storage technology can support a broad range of commercial applications from vehicles to power generation to appliances and consumer electronics. Coupled with fuel cell technology, our solid hydrogen storage device could provide enough fuel to power a laptop for a month or a vehicle for hundreds of miles on a single charge. The scalability of this hydrogen storage system to any size makes it the ultimate fuel solution to hydrogen dependent applications."

 

[f95toli]

I doubt that is correct. Superfluid helium is almost impossible to contain but even then the leakage is extremely small if you use for example a stainless steel container (it will leak through glass).
You will alwats have some diffusion through the walls of the container but 1.7 percent sounds like a very high number, this process it is also temperature dependent.

Besides, I might be wrong think there is something wrong with that figure: There should be a volume/surface area dependendence since the amount of leakage should be proportional to the amount of hydrogen that actually touches the walls of the container.
To say that is is always 1.7 percent regardless of the shape of the container sounds strange to me.

 

[DrPizza]

Originally posted by: f95toli
I doubt that is correct. Superfluid helium is almost impossible to contain but even then the leakage is extremely small if you use for example a stainless steel container (it will leak through glass).
You will alwats have some diffusion through the walls of the container but 1.7 percent sounds like a very high number, this process it is also temperature dependent.

Besides, I might be wrong think there is something wrong with that figure: There should be a volume/surface area dependendence since the amount of leakage should be proportional to the amount of hydrogen that actually touches the walls of the container.
To say that is is always 1.7 percent regardless of the shape of the container sounds strange to me.

Perhaps the minimum figure represents a spherical storage container which minimizes the surface area in contact with the hydrogen?

Also, just a guess, but I think the claim of "solid storage" is just storing it in a more or less stable chemical form - some sort of hydride perhaps.

 

[sao123]

does a safe and efficient method exist which produces

2 H2O -> 2H2 + O2

which could be useful for storing water (highly abundant) and producing hydrogen as fuel?

 

[Matthias99]

Originally posted by: sao123
does a safe and efficient method exist which produces

2 H2O -> 2H2 + O2

which could be useful for storing water (highly abundant) and producing hydrogen as fuel?

Yes, electolysis. Requires a lot of electrical power input, though, and distilled water for good results. Also not real fast unless the system is fairly large, IIRC.

 

[imported_StormGod]

I can think of one method of storing hydrogen in such a manner that *none* will leak. Heat it to a plasma (in this case until it is more stable as atomic hydrogen than as molecular hydrogen) and then stuff it in a magnetic bottle. Voila, none of the H+ ions will be able to escape from super-high flux magnetic bottles like those being used to contain fusion plasma. Now of course, it would take an *insane* amount of energy to maintain this storage solution. So the real answer to your question is "not yet".

 

[rgwalt]

Originally posted by: sao123
does a safe and efficient method exist which produces

2 H2O -> 2H2 + O2

which could be useful for storing water (highly abundant) and producing hydrogen as fuel?

Electrolysis is safe, but it is not efficient.

Zeolites and carbon nanotubes both may have applications in hydrogen storage. However, for now, hydrogen is very difficult to store.

As to the above comments, giving a rate of leakage would seem incorrect. The amount of flux of hydrogen will depend on the thickness of the tank it is stored in. So, if I have a sphere that has walls 1 mile thick and is made of stainless steel, I doubt I would lose any hydrogen... maybe a stray molecule or two.

R

 

[NeoPTLD]

Originally posted by: sao123
does a safe and efficient method exist which produces

2 H2O -> 2H2 + O2

which could be useful for storing water (highly abundant) and producing hydrogen as fuel?

2H2 + O2 -> 2 H2O + -x kJ (exothermic reaction)

2H2O -> 2H2 + O2 + x + n kJ (endothermic reaction. The addition of n is to account for less than perfect efficiency of electrolysis process)

So, to make a mole of hydrogen, it takes more energy than burning a mole of hydrogen can produce and the energy must be in form of electrical power.

Where are we going to get that power? I have no idea.

 

[Paratus]

Originally posted by: NeoPTLD

Originally posted by: sao123
does a safe and efficient method exist which produces

2 H2O -> 2H2 + O2

which could be useful for storing water (highly abundant) and producing hydrogen as fuel?

2H2 + O2 -> 2 H2O + -x kJ (exothermic reaction)

2H2O -> 2H2 + O2 + x + n kJ (endothermic reaction. The addition of n is to account for less than perfect efficiency of electrolysis process)

So, to make a mole of hydrogen, it takes more energy than burning a mole of hydrogen can produce and the energy must be in form of electrical power.

Where are we going to get that power? I have no idea.

On board the international space station we use solar power converted to electricty to convert water into O2 and H2. The H2 is dumped overboard currently. This process is performed by a Russian piece of equipment called an Elektron. IT's been having problems recently. You can probably find some articles on it at space.com

 

[bcoupland]

Paratus are you an astronaut?

 

[Paratus]

Originally posted by: bcoupland
Paratus are you an astronaut?

No I'm not an astronaut but I do work on the International Space Station Program.

 

[Yolner]

Originally posted by: Paratus

Originally posted by: bcoupland
Paratus are you an astronaut?

No I'm not an astronaut but I do work on the International Space Station Program.

Sounds like a fun job

 

[deldd]

Originally posted by: Yolner

Originally posted by: Paratus

Originally posted by: bcoupland
Paratus are you an astronaut?

No I'm not an astronaut but I do work on the International Space Station Program.

Sounds like a fun job

A very cool job.

 

[DrPizza]

Originally posted by: NeoPTLD

Originally posted by: sao123
does a safe and efficient method exist which produces

2 H2O -> 2H2 + O2

which could be useful for storing water (highly abundant) and producing hydrogen as fuel?

2H2 + O2 -> 2 H2O + -x kJ (exothermic reaction)

2H2O -> 2H2 + O2 + x + n kJ (endothermic reaction. The addition of n is to account for less than perfect efficiency of electrolysis process)

So, to make a mole of hydrogen, it takes more energy than burning a mole of hydrogen can produce and the energy must be in form of electrical power.

Where are we going to get that power? I have no idea.

Well, currently we get most of that power by burning fossil fuels. The trade-off comes when we consider a power plant's efficiency and pollution contribution compared to a car's efficiency and pollution

 

[Smilin]

Originally posted by: DrPizza

Originally posted by: NeoPTLD

Originally posted by: sao123
does a safe and efficient method exist which produces

2 H2O -> 2H2 + O2

which could be useful for storing water (highly abundant) and producing hydrogen as fuel?

2H2 + O2 -> 2 H2O + -x kJ (exothermic reaction)

2H2O -> 2H2 + O2 + x + n kJ (endothermic reaction. The addition of n is to account for less than perfect efficiency of electrolysis process)

So, to make a mole of hydrogen, it takes more energy than burning a mole of hydrogen can produce and the energy must be in form of electrical power.

Where are we going to get that power? I have no idea.

Well, currently we get most of that power by burning fossil fuels. The trade-off comes when we consider a power plant's efficiency and pollution contribution compared to a car's efficiency and pollution

The current plan is to use Coal plants to produce the electricity to produce the hydrogen. We then use the hydrogen to propel cars.

The *efficiency* of the power plant won't matter. It's not propeling the car. The car's engine is propelling the car. Regardless of the fuel used it will be less efficient. The only part of the trade off that matters is the pollution part.

Although hydrogen doesn't produce any pollution (just warm water) the efficiency of the engines isn't much better than current gasoline internal combustion engines. Due to the ineffeciency we'll be using more hydrogen instead of gasoline to get a given amount of energy. Of course this means more hydrogen will need to be produced. The net result is we burn more coal and less gasoline.

Most of our coal power plants have been grandfathered in under EPA and energy policies. All-in-all the hydrogen powered cars of the future may turn out to be an environmental nightmare. If some policy shifts come along as well it could work out well though. I'll respect the highly technical forum and keep my political views out of this. Suffice to say there can only be one president who holds the record for the worst environmental record at any given time. I'll tell you that George Washington isn't the current record holder. I won't say who is. :|

 

[Paratus]

Originally posted by: Smilin

Originally posted by: DrPizza

Originally posted by: NeoPTLD

Originally posted by: sao123
does a safe and efficient method exist which produces

2 H2O -> 2H2 + O2

which could be useful for storing water (highly abundant) and producing hydrogen as fuel?

2H2 + O2 -> 2 H2O + -x kJ (exothermic reaction)

2H2O -> 2H2 + O2 + x + n kJ (endothermic reaction. The addition of n is to account for less than perfect efficiency of electrolysis process)

So, to make a mole of hydrogen, it takes more energy than burning a mole of hydrogen can produce and the energy must be in form of electrical power.

Where are we going to get that power? I have no idea.

Well, currently we get most of that power by burning fossil fuels. The trade-off comes when we consider a power plant's efficiency and pollution contribution compared to a car's efficiency and pollution

The current plan is to use Coal plants to produce the electricity to produce the hydrogen. We then use the hydrogen to propel cars.

The *efficiency* of the power plant won't matter. It's not propeling the car. The car's engine is propelling the car. Regardless of the fuel used it will be less efficient. The only part of the trade off that matters is the pollution part.

Although hydrogen doesn't produce any pollution (just warm water) the efficiency of the engines isn't much better than current gasoline internal combustion engines. Due to the ineffeciency we'll be using more hydrogen instead of gasoline to get a given amount of energy. Of course this means more hydrogen will need to be produced. The net result is we burn more coal and less gasoline.

Most of our coal power plants have been grandfathered in under EPA and energy policies. All-in-all the hydrogen powered cars of the future may turn out to be an environmental nightmare. If some policy shifts come along as well it could work out well though. I'll respect the highly technical forum and keep my political views out of this. Suffice to say there can only be one president who holds the record for the worst environmental record at any given time. I'll tell you that George Washington isn't the current record holder. I won't say who is. :|

Quite frankly the best way and least polluting way would be to crack the water using nuclear power. No green house producing gases that way. Since fission is so much more efficient than burning fossil fuel you end up with nasty but much smaller amount of pollutants and waste that cause a local problem instead of the global problem that coal and oil cause.


To Yolner & Deldd

The job definatley has a lot of cool points. But its got its downsides. Since we fly 24/7 I end up working weird hours, (nights & weekends) sometimes. Hard on the family life.

 

[Smilin]

Nuclear power would definately be the way to go. Furthermore electric cars would completely bypass the ineffeciencies of internal combustion engines. Batteries and fuel cells still have a way to go but IC Engines just plain suck. What are they like 40-60% efficient?

It's a long way from reality right now though. Most of our power is produced by coal. Ramping up nukes would help, we haven't had many plants built since 3-mile island. Nuclear power pretty much came to a standstill in this country back then. Really coal wouldn't even be that bad if we would actually produce some new plants. Retrofitting the old ones so they can handle pulverized coal dust just doesn't really do it. Our EPA regulations are sad right now.

 

[fuzzynavel]

use nuclear fuel then blast the containers of waste into the sun!....there are millions of nuclear contaminants there.....a few extra bits won't hurt!

 

[Runamile]

Originally posted by: fuzzynavel
use nuclear fuel then blast the containers of waste into the sun!....there are millions of nuclear contaminants there.....a few extra bits won't hurt!

IIRC, that thought has been explored, but turned down(for now at least). The reason is - what if something happened to the ship during take-off? Even though space travel has one of the best transporation records in the world, if that sucker blows up in the upper atmophere, and dumps tons and tons of nuclear waste into the sky, we are screwed.

 

[Jeff7]

Most of our coal power plants have been grandfathered in under EPA and energy policies. All-in-all the hydrogen powered cars of the future may turn out to be an environmental nightmare. If some policy shifts come along as well it could work out well though. I'll respect the highly technical forum and keep my political views out of this. Suffice to say there can only be one president who holds the record for the worst environmental record at any given time. I'll tell you that George Washington isn't the current record holder. I won't say who is.

Quite frankly the best way and least polluting way would be to crack the water using nuclear power. No green house producing gases that way. Since fission is so much more efficient than burning fossil fuel you end up with nasty but much smaller amount of pollutants and waste that cause a local problem instead of the global problem that coal and oil cause.

Fission, or hopefully fusion eventually.
There's also solar power. Granted, photovoltaics aren't too efficient, but they don't exactly have any emissions.
And maybe you could put thermoelectric generators on the back of the panels, as they're likely to get hot sitting in the sun all day, so might as well put that energy to use too.

And hey, maybe if fission proves to be a good enough power source, we could use some hydrogen to propel rockets, and launch the nuclear waste into the sun, without causing the pollution of conventional engines. However, I don't know that burning hydrogen can produce enough thrust to efficiently lift large amounts of material.
Maybe some kind of electromagnetic slingshot launcher? Or maybe an orbital tether station.