Molecular sieve regeneration - Clean it first?
Molecular sieve regeneration - Clean it first?
(OP)
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?
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?





RE: Molecular sieve regeneration - Clean it first?
They can probably explain it all to you.
Good luck
Cryo
"Math is the ruler of your potential succes...."
RE: Molecular sieve regeneration - Clean it first?
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?