It seems to me that some type of in-line filter could be used to separate gases from each other.
The filter above is designed to capture Nitrogen.
Some work by absorbing, but I would favor a type that simply splits the gases up allowing use of whichever gas you choose and send the others elsewhere.
I think this might be also used to REMOVE nitrogen from the gas stream.
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I was working as a computer contractor at the JEEP/TRUCK ENGINEERING facility, Instrumentation Department for Chrysler Corporation in Detroit back in 1992.
They were having serious NOx problems with the V-12 engine used in the new Dodge Viper car.
I suggested to an engineer co-worker of mine that they should use a Nitrogen filter,
No Nitrogen no NOx.
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Of course my idea went no further.
Links:
NOx is Nitrogen & Oxygen Mixed at High Temperatures
Like in a car engine
NOx - Wikipedia
Nitrogen Membrane
Nitrogen Generator
