antibody
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size of formaldehyde molecule and 3A molecular sieves
I'm thinking of using 3A molecular sieves to help drive the imine formation using formaldehyde and a much larger amine.
I realize that a formaldehyde molecule is not much larger than a water molecule which will get trapped in a 3A sieve, but I am unsure whether or not
formaldehyde would get caught in a 3A sieve.
The 3A sieves have pore sizes of 3 angstrom, but I am unsure how to determine the size of a formaldehyde molecule.
Would 3A sieves trap formaldehyde?
Thanks so much!
[Edited on 1-3-2011 by antibody]
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Chordate
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Depends on the sort of molecular sieves you are using. Some molecular sieves will vary in their pore diameter. 3A molecular sieves will preferentially
absorb water but very little formaldehyde, while a 4A sieve will preferentially absorb formaldehyde.
Since process control is hard chances are you will lose a little bit of the formaldehyde to the sieve (pore size does vary), but it shouldn't be a
huge amount.
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antibody
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Thank you Chordate.
I'll use just enough sieves to absorb the amount of H2O I anticipate being produced by this reaction. And maybe add them part way through the reaction
so they aren't absorbing formaldehyde before any H2O is produced.
The sieves I have in mind are made of aluminosilicate. Is there another type that might be better suited to this application IYO ?
[Edited on 2-3-2011 by antibody]
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