gas separation project

Brian_B

This project has been rolling around my head for awhile ,it came to me a day or so after my mom started using a oxygen concentrator. I went to the store to get a tank of argon welding gas and started envisioning a device that could produce argon so that I wouldn't have to run to the welding shop all the time.


I did a little research and found that argon is in the air we breath and can be separated out by fractional distillation or by using a molecular sieve (or at least oxygen can be separated that way).


Is argon ( or other gasses) generation / separation something that can be done in the home shop ?


Any thoughts or feedback would be greatly appreciated.


Brian

kwinn

Argon is produced commercially by fractionating liquid air. AFAIK there is no other practical way to produce it, certainly not one that would be practical for use in a home shop.

Brian_B

Thanks' kwinn,
That is the route I'm headed, I bought the book "Illustrated Guide to Home Chemistry Experiments: All Lab, No Lecture" By Robert Bruce Thompson and have been working through the experiments to make sure I fully understand chemistry before I move forward. I figure it will take me all summer to get done with the book and then I can move forward next winter.

Thanks'
Brian

Mark_T

Titanium burns in pure nitrogen so that in theory heating titanium with air will react all the oxygen and
nitrogen leaving argon (I presume CO2 will split to yield oxygen).

Its not a cheap route to argon and needs high temperatures.

Also found this: http://www.restek.com/Technical-Resources/Technical-Library/Petroleum-Petrochemical/petro_A009

abecedarian

Transcripts and other documents relating to Sir Rayleigh's experiments and lectures where he describes his experiments isolating Argon may be useful.
Here's one transcript: http://web.lemoyne.edu/~giunta/ea/RAYLEIGHann.html

Brian_B

abecedarian and Mark_T,
Thanks' for the info , I'll check that stuff out.

Here is another thought that crossed my mind ,being that oxygen ,nitrogen and argon are different in molecular size (see pdf), would it be possible to build a air "gravel screening plant" on a silicon chip ? I've seen some amazing sensors out there that have micro passage ways on them.

Thanks'
Brian

Publison

But how long would it take to fill a 20# tank?

abecedarian

That sounds like a variation of pressure swing adsorption. So maybe it would be possible to combust some material, (hydrogen gas, maybe?) to remove the oxygen (water as byproduct), then PSA remove the nitrogen?

Brian_B

@ Publison,
Well running at a clock speed of 80 MPS ( 80,000,000 argon molecules per second) , 20 lbs of argon would take 90,000,000,000,000 years to separate (give or take a year) , But I'm hoping to double that speed in a year .


Brian

Publison

Brian_B wrote: »

@ Publison,
Well running at a clock speed of 80 MPS ( 80,000,000 argon molecules per second) , 20 lbs of argon would take 90,000,000,000,000 years to separate (give or take a year) , But I'm hoping to double that speed in a year .


Brian

LOL

kwinn

Most of the nitrogen can be removed now by a process similar to what is used in the oxygen concentrators currently available, but that leaves the removal of the oxygen to consider. If the removal or large scale reduction of both nitrogen and oxygen could be done it might be practical to separate the remaining constituents. Stress on the "might".

PropGuy2

I worked on a project years ago that used ion mobility to separate out gases, ions, molecules. Two ways (1) use a ion mobility cell with opposite charged plates at 1000 VDC or so AND/OR (2) ion spectrometry, a long (about 6 feet) very thin tube a couple thousands in diameter. Not very common but they work.

Brian_B

@PropGuy2,
Is this the way that lighting releases nitrogen in a thunderstorm ?

Thanks'
Brian

mklrobo

Brian_B wrote: »

This project has been rolling around my head for awhile ,it came to me a day or so after my mom started using a oxygen concentrator. I went to the store to get a tank of argon welding gas and started envisioning a device that could produce argon so that I wouldn't have to run to the welding shop all the time.


I did a little research and found that argon is in the air we breath and can be separated out by fractional distillation or by using a molecular sieve (or at least oxygen can be separated that way).


Is argon ( or other gasses) generation / separation something that can be done in the home shop ?


Any thoughts or feedback would be greatly appreciated.


Brian

Sounds like a cool :cool: challenge. There are many ways to produce what you want. The deal is, what resources do you have to produce the product you want. If you can provide
a list of chemicals readily avaliable, I may be able to come up with the Stociemetric equation to calculate the moles, in oz, grams, lbs, or tons.

Lawson

Well, this Instructable might be relevant. http://www.instructables.com/id/Homemade-liquid-nitrogen-generator/ or http://homemadeliquidnitrogen.com/

Just need to add a pre-cooler to condense out water and CO2 then a distillation stage onto the end. Easy right? :-P

mklrobo

Lawson wrote: »

Well, this Instructable might be relevant. http://www.instructables.com/id/Homemade-liquid-nitrogen-generator/ or http://homemadeliquidnitrogen.com/

Just need to add a pre-cooler to condense out water and CO2 then a distillation stage onto the end. Easy right? :-P

Safety should be used when using any system like this. whatever process you decide on, energy will be consumed and/or released in each stage. Structures inplace will have to withstand
elements corrosion, or unusual reactions. Internal seperation membranes will follow suit. If too much of an undesired product is produced, a purge in put inplace; assuming the
elements purges are enviromentally safe.