Chromatography Forum

http://www.instructables.com/id/Nitrogen-gas-generator/

Someone needs to try it out.

Peter

Be our guest, Peter. Take pictures, write a will.

Be our guest, Peter. Take pictures, write a will.

Of course it will work safely - I saw it on the internet

Peter

And when you're finished you can hook it up to this:

http://hackaday.com/2014/05/23/homemade ... -nitrogen/

Not a chance, we never get snow in northern Botswana.

Peter

We're talking about 100 psi or so here. Your brass gas lines are probably close to that. For a DIY project, this puppy is really impressive (welding, fabrication, valving, electronics, programming, etc.....). Only thing I could not figure out was his valving sequence. From one CMS chamber to the second or one gulp goes straight to the reservoir?

Best regards,

AICMM

They alternate. The design is very similar to commercial generators that go "Click-BAAaaaaaahhhhhhpffffffffffff" every minute or so. The idea is that pressurised air is fed to first column, and the oxygen preferentially enters the beads, so the stuff coming out the end is mostly nitrogen. After a while it's getting over-filled and oxygen is penetrating too far up the column and purity would fall, so at this stage the column inlet is opened to the atmosphere so that the oxygen can diffuse back out of the particles and the back-flow of pressurised gas can whoosh it all back out to exhaust. While it's doing so, there would be no further generation of nitrogen, so to keep the system going, manufacturers make the system as a double system, so column 2 can generate while column 1 is regenerating itself.

There is no particular reason why you shouldn't build a one-column generator which only fills its nitrogen reservoir part of the cycle-time, but it wouldn't be so useful for continuous demand applications like LC-MS, and it wouldn't use the air-compressor so efficiently.

They alternate. The design is very similar to commercial generators that go "Click-BAAaaaaaahhhhhhpffffffffffff" every minute or so. The idea is that pressurised air is fed to first column, and the oxygen preferentially enters the beads, so the stuff coming out the end is mostly nitrogen. After a while it's getting over-filled and oxygen is penetrating too far up the column and purity would fall, so at this stage the column inlet is opened to the atmosphere so that the oxygen can diffuse back out of the particles and the back-flow of pressurised gas can whoosh it all back out to exhaust. While it's doing so, there would be no further generation of nitrogen, so to keep the system going, manufacturers make the system as a double system, so column 2 can generate while column 1 is regenerating itself.

There is no particular reason why you shouldn't build a one-column generator which only fills its nitrogen reservoir part of the cycle-time, but it wouldn't be so useful for continuous demand applications like LC-MS, and it wouldn't use the air-compressor so efficiently.

We have one in the lab that is a single column with reservoir that feeds our GC/ECD and TOC instruments. Produces a steady 800ml/min at 60psi from 100psi incoming compressed air. Reservoir fluctuates from 65 to 85psi nitrogen.

For LCMS you would probably need several columns working in a combination of parallel/series to produce enough flow, that is why most of those units are membrane ones.