[vdblnkr34 (OP)]

Hi.
Can i pump O2 and H2 with performance fuel pump for sport cars?

[Origin]

Could you clarify your question?  Do you want to run the car on only oxygen and hydrogen?  Do you want to use liquid O2 and liquid H2 or gasses?

[Bored chemist]

Can i pump O2 and H2

Yes, separately.

[vdblnkr34 (OP)]

Could you clarify your question?  Do you want to run the car on only oxygen and hydrogen?  Do you want to use liquid O2 and liquid H2 or gasses?

Gases, yes. Separated. Need to move them into the storage silo under atmospheric pressure or something.

[vdblnkr34 (OP)]

Can i pump O2 and H2

Yes, separately.

Nice to know it will work, thanks.

[alancalverd]

Car fuel pumps deliver small volumes of liquid at high pressure and low flow rates. Consider a high performance car running at 300 kph and consuming 0.25 l/km - the pump is delivering .020 liter per second, or around 18 gram/second of gasoline. assuming the energy densities are similar, the car would need 18 grams of hydrogen gas = 200 liters at atmospheric pressure per second. That's quite a different pump - more like a fan.

When you consider filling the storage vessel it's worth comparing filling rates with liquid fuels. 1000 liter/minute of gasoline or diesel is on the slow side, and the fuel density is  10,000 times that of hydrogen gas, so to shift the same amount of potential energy in a reasonable time you will need to pump 10,000,000 liters of hydrogen per minute - a serious turbine.

[vdblnkr34 (OP)]

I was planning to pick it up from electrolysis of water.  Dont need a big pump, than from a storage silo will need to convert it or compress it more or into liquid state.

I was thinking to find out.
How much mol of hydrogen in cubic meter? And how much mol of propane in cubic meter?

[Origin]

I was thinking to find out.
How much mol of hydrogen in cubic meter? And how much mol of propane in cubic meter?

A mole of gas is about 22.4 liters @ STP.
A car will run (not very well) on hydrogen gas and air, but I doubt it would be very good for the car in the long run.

[evan_au]

A mole of gas is about 22.4 liters @ STP.*

Since there is 1,000 liters in a cubic meter, that is 45 moles per cubic meter, for both Hydrogen and Propane.
- But when you look at the energy content, a mole of Propane (C₃H₈) has far more hydrogen atoms than 1 mole of hydrogen (H₂).
- Propane has heat of combustion of 2.2 MJ/mol
- Hydrogen has heat of combustion of 0.29 MJ/mol
- The reason Hydrogen might be preferred in some applications is that it doesn't release CO₂ when burnt
https://en.wikipedia.org/wiki/Propane
https://en.wikipedia.org/wiki/Hydrogen

*This is at 1 atmosphere of pressure. In practice, both Hydrogen & Propane are stored under pressure.
- The difference is that Propane becomes a liquid, and that stores energy in a very compact way (eg in a taxi fuel tank)
- Hydrogen does not become a liquid at everyday temperatures, so it takes up a very large amount of space for the energy it contains (a taxi of equivalent range would have no room for passengers or luggage).

[vdblnkr34 (OP)]

Will need 7.5 times more of hydrogen gas. Not so bad i guess.
Can hydrogen be compressed?
Does hydrogen react with water any how?

[Origin]

Can hydrogen be compressed?

Of course, it's a gas.

Does hydrogen react with water any how?

Not at normal temperatures and pressures.

[alancalverd]

What matters for a vehicle isn't heat of combustion per mole, but per kilogram - energy density. Hydrogen delivers 141.8 MJ/kg, all liquid fossil fuels around 40 - 50 MJ/kg.
Liquid hydrogen is the ideal fuel (which is why it is used for rockets) but has presented handling and storage problems in the past. I think the engineering problems have actually been tackled very effectively in MRI machines, where loss of liquid helium is dangerous and expensive, so I see hydrogen as the fuel of the future, with 100 times the energy density of batteries. 
You can run an internal combustion engine on hydrogen with a bit of modification, and that would make an intermediate step towards all-fuel-cell electric propulsion. An alternative route would be to hydrogenate organic waste to produce a more conventional liquid fuel, simply using carbon /carbon dioxide as a recyclable  "carrier" for the energy invested in electrolysis.   

[evan_au]

When considering effectiveness of a power source, you need to consider:
- MJ/litre: How much of the space is taken up by energy storage?
- MJ/kg: How much mass do you need to power it?

Stationary applications aren't really bothered by:
- MJ/litre: just use a huge storage tank, like the old Town Gas "gasometers"
- MJ/kg:  You don't have to accelerate it anywhere, so mass is not so critical

Vehicle applications are more bothered by:
- MJ/litre: The vehicle needs to fit within 1 lane of the road, and still carry a useful load. Hydrogen gas at atmospheric pressure is really poor by this measure; pressurized hydrogen gas is better, but not enough to match liquid petroleum gas.
- MJ/kg:  You have to accelerate and decelerate the fuel every time the vehicle starts and stops. Hydrogen is pretty good by this measure. But using regenerative braking in conjunction with a battery can double the fuel efficiency (at least for city driving).

[vdblnkr34 (OP)]

Also should be good to burn oxygen with hydrogen together?

[Bored chemist]

When considering effectiveness of a power source, you need to consider:
- MJ/litre: How much of the space is taken up by energy storage?
- MJ/kg: How much mass do you need to power it?

Stationary applications aren't really bothered by:
- MJ/litre: just use a huge storage tank, like the old Town Gas "gasometers"
- MJ/kg:  You don't have to accelerate it anywhere, so mass is not so critical

Vehicle applications are more bothered by:
- MJ/litre: The vehicle needs to fit within 1 lane of the road, and still carry a useful load. Hydrogen gas at atmospheric pressure is really poor by this measure; pressurized hydrogen gas is better, but not enough to match liquid petroleum gas.
- MJ/kg:  You have to accelerate and decelerate the fuel every time the vehicle starts and stops. Hydrogen is pretty good by this measure. But using regenerative braking in conjunction with a battery can double the fuel efficiency (at least for city driving).

The killer is MJ/£ or $
So far in this thread the OP has come up with lots of ways to get fewer MJ for more £.

[vdblnkr34 (OP)]

Yes its true. Like $5 a litter. But, prices for gasoline are growing and soon price for fuel will be like cigarettes' today. And it will be profitable than. 

[alancalverd]

NASA pays less than $4 per kilogram for liquid hydrogen, with pretty much the same potential combustion energy as a gallon of diesel, in about twice the volume and a quarter of the weight. Totally feasible and competitive.

[alancalverd]

Also should be good to burn oxygen with hydrogen together?

No problem. Oxygen is indeed free of charge at present, though there are Government plans to privatise the atmosphere. The Opposition intends to nationalise and tax it instead.

[vdblnkr34 (OP)]

NASA pays less than $4 per kilogram for liquid hydrogen, with pretty much the same potential combustion energy as a gallon of diesel, in about twice the volume and a quarter of the weight. Totally feasible and competitive.

Can i sell them some liquid hydrogen too?

[evan_au]

Apparently, NASA's new Space Launch System requires so much liquid Hydrogen that they can't currently store enough on site.

When they get ready for a launch, they pump the liquid Hydrogen from their big storage tank into the rocket
- If they scrub the launch, they can pump the remaining liquid hydrogen back into the tank
- But while the rocket is sitting on the launch pad, they allow the Hydrogen to boil off as a very effective and low-mass method of keeping the liquid Hydrogen cool.
- Apparently, if they scrub the launch, there is not enough liquid hydrogen left onsite for another launch attempt the same day....

Maybe you could start by selling them another liquid Hydrogen tank (with built-in-refrigerator).