Is Separating Oxygen from Air Feasible Without Increasing Pollution?

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Separating oxygen from air is feasible through methods like fractional distillation and using zeolite materials in oxygen concentrators, which can yield high-purity oxygen. However, introducing pure oxygen into internal combustion engines (ICE) poses significant risks, including overheating and increased danger of combustion. While some argue that higher oxygen concentrations could improve engine efficiency, others contend that it may not lead to better fuel efficiency and could actually increase nitrogen oxides (NOx) emissions. Turbocharging is suggested as a more effective way to enhance engine power without the risks associated with pure oxygen. Overall, while oxygen separation is technically possible, its application in automotive engines raises concerns about safety and pollution.
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is it possible to separate oxygen from air?

in other words, getting pure oxygen from air
 
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damn, that sounds like its going to take a long time. i was seeing if it was possible to get a car to suck in pure oxygen instead of air, but it would have to make a lot of oxygen in a short period of time

thanks
 
Quadruple Bypass said:
damn, that sounds like its going to take a long time. i was seeing if it was possible to get a car to suck in pure oxygen instead of air, but it would have to make a lot of oxygen in a short period of time

thanks
If it were easy, do you think they wouldn't already have thought about it? :smile:
 
fractional distillation or burn hydrogen, collect the water, preform electrolysys and separate the gases, reuse the H2 and use the O2
 
Hi QB,
Quadruple Bypass said:
is it possible to separate oxygen from air?

in other words, getting pure oxygen from air
Just a disclaimer first: saying "pure" is relative. There are always contaminants in your product, regardless of the method used. Even distillation is only going to give 99.99xx percent purity.

There are plenty of other ways of obtaining enriched oxygen. PSA and other methods using membranes or adsorption are common. Here's a decent overview:
http://www.uigi.com/noncryo.html

As for putting oxygen into an engine however, there's no reason to do that. First, an oxygen rich stream in an ICE is going to overheat the engine. Second, it's extremely dangerous - even steel burns readily in a pure oxygen environment at any significant pressure. And third, it don't believe it improve efficiency. I'm not absolutely sure about the efficiency part, but I know there have been discussions in the ME forum about this. Might want to do a search in the engineering forums, there was a discussion not too long ago.
 
It is possible to separate oxygen from air using zeolite materials in machines known as oxygen concentrators. These devices are used by people needing to breathe higher concentrations of oxygen because of various medical conditions. These machines can provide ~5 liters/minute of 95%+ oxygen.
To learn more about this please read about "oxygen concentrators" and "zeolites" on the wikipedia website.
 
Q_Goest said:
And third, it don't believe it [will] improve efficiency. I'm not absolutely sure about the efficiency part, but I know there have been discussions in the ME forum about this. Might want to do a search in the engineering forums, there was a discussion not too long ago.
It won't. The fuel/air mixture is precisely controlled to provide exactly the amount of oxygen necessary for efficient combustion.
 
Quadruple Bypass said:
is it possible to separate oxygen from air?

in other words, getting pure oxygen from air


Yes, try breathing :wink:
 
  • #10
russ_watters said:
It won't. The fuel/air mixture is precisely controlled to provide exactly the amount of oxygen necessary for efficient combustion.
Don't understand what you mean; if you can introduce more oxygen in the combustion chamber, you can also introduce more combustible, so you have more power.
For "spark ignition" engines (example gasoline engines) there would be the problem to control pre-ignition and detonation, but for "compression ignition" engines (example Diesel engines) there wouldn't be such problem and power would increase dramatically, and pollution would decrease dramatically.
 
  • #11
lightarrow said:
Don't understand what you mean; if you can introduce more oxygen in the combustion chamber, you can also introduce more combustible, so you have more power.
If that's the goal, a turbocharger does a great job of doing exactly that.
...and power would increase dramatically...
Yes.
...and pollution would decrease dramatically.
Why? You've changed nothing about the chemistry of the combustion.

Depending on how you think about it, a turbocharger may increase or decrease fuel consumption. A turbocharger does increase the thermodynamic efficiency of an engine, but the net effect of adding a turbocharger to an existing engine is and increase in power and an increase in fuel consumption. But if, for example, you are looking for a car with 250hp and your choices are a 3.6L V6 and a 2.0L turbocharged 4cyl (both generating 250hp), the turbo 4cyl will use less fuel.
 
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  • #12
russ_watters said:
Don't understand what you mean; if you can introduce more oxygen in the combustion chamber, you can also introduce more combustible, so you have more power.
If that's the goal, a turbocharger does a great job of doing exactly that.
Have you ever heard of using compressed N2O injected in the combustion chamber to increase power? O2 it's not used just because the bottle/cylinder contains less of it so it finishes soon.
...and pollution would decrease dramatically
Why? You've changed nothing about the chemistry of the combustion.
You don't change the chemistry but you change the physics. You have much less HC with an higher percent of oxygen, because the combustion is more efficient (O2 is less diluted by N2); furthermore, if N2 percent is very low, you would have much less NOx.
 
  • #13
if you get the right mixture of fuel and oxygen the combustion is more efficent like with cutting tourches in short is what he is looking for the fuel to oxygen ratio is the key
 
  • #14
This thread is over a year old.
 
  • #15
wouldn't introducing high oxygen concentration to an ICE increase NOX; therefore increasing pollution? Or having to get a bigger EGR valve
 
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