Determining Adsorption of CO2 with Microporous Polymer

[Sancho Panza]

Hello, I am trying to come up with a easy method of determining amount of gas, in this case CO₂ adsorbed onto a solid adsorbent. The adsorbent i am going to use is microporous polymer (MP).

So, if it has to be as simple as it can be, I think I should measure change in weight. At this point I am thinking about using Schlenk flask, in which i would place MP, heat it up and then suck out the air out of the flask and make vacuum. This process should cleanse the MP of any adsorbed air. What I want to do next, is measure weight of clean MP and then fill the flask with CO₂, and let it "sit" there for a time in which all surface of MP should be covered in layers of CO₂. After this I would once again make vacuum inside of the flask and measure the weight of now occupied MP, then it is just matter of calculations.

And finally my questions are, could this method work? I am aware that while adding the CO₂ I might have it contaminated with air, but would be the contamination insignificant enough to the point I can just not count with it? Also the part of my plan I am not sure is good idea, is when I would try to make vacuum 2nd time to measure the change in weight, because I think that while sucking the air out, a desorption might occur and lead to loss of some adsorbed CO₂. Should I rather try to measure the change of pressure to get information on how much CO₂ is adsorbed (well, if it could work this way)? Any ideas how to improve this method or just completely forget it find a new way?

 

[TeethWhitener]

Also the part of my plan I am not sure is good idea, is when I would try to make vacuum 2nd time to measure the change in weight, because I think that while sucking the air out, a desorption might occur and lead to loss of some adsorbed CO2.

This will be your biggest problem.

Should I rather try to measure the change of pressure to get information on how much CO2 is adsorbed (well, if it could work this way)?

Yes. Look up "gas adsorption experiment" for experimental details, and you might want to look at BET theory and Langmuir theory for the theory behind gas adsorption on a surface.

 

[Sancho Panza]

This will be your biggest problem.Yes. Look up "gas adsorption experiment" for experimental details, and you might want to look at BET theory and Langmuir theory for the theory behind gas adsorption on a surface.

Thanks! I got my hands on very interesting articles about my problems.