Molecular sieve regeneration - Clean it first?

[bobtr1]

I am designing a molecular sieve module to lower the moisture content of a solvent from 0.5% down to 0.05%. The solvent is NMP, N-Methyl-2-Pyrollidone, typically used as a paint stripper.

I plan on using nitrogen flow at 200C to 250C for 4 to 8 hours to regenerate the sieve.

NMP has a very low volatility and is typically removed from parts using an acetone rinse.

I am concerned that the NMP may be hard to remove from the molecular sieve beads using only nitrogen.

Should I add a step to rinse the sieve with acetone before I start the nitrogen flow?

 

[cryotechnic]

It's an interesting question, but in this case, the best thing to do is ask your supplier/manufacturer of the moleculair sieve.
They can probably explain it all to you.

Good luck

Cryo


"Math is the ruler of your potential succes...."

 

[Zoobie]

I agree with cryotechnic on this. In this case, the vendor will have the best information.

However, maybe you can answer some questions which may generate some useful responses. What type of sieve are you using (3A, 13X, etc.)? I believe that the NBP of NMP is somewhere around 200C. Is this correct? Ideally your sieve will not adsorb any NMP so as long as your regen gas is hot enough (but not too hot) then I can't see why you would need to use a solvent. Your goal is to remove the water anyways not the solvent.

I also have a question of my own for the experts. I agree that acetone is a solvent for NMP. However, if by some chance NMP were adsorbed to the sieves, will acetone absorb NMP?