adi54 - 24-3-2006 at 22:34
Can you please tell me best recovery method for acetaldehyde from acetaldehyde-NOx gas mixture?
vulture - 25-3-2006 at 14:05
Adduct formation with sulfites? Sulfite decomposition by acid traces (NOx + H2O) is going to cause problems though.
EDIT: I just realized the adduct might not be reversable...
Selective cold trap? The boiling points of NOx and acetaldehyde differ quite a bit.
[Edited on 25-3-2006 by vulture]
garage chemist - 25-3-2006 at 15:17
Wash the gas with ammonia solution. The acetaldehyde will form the ammonia trimer (dissolved in the water), from which it can be recovered by heating
with dilute H2SO4.
An alternative would be selective absorption with a suitable solvent. The solvent can then be stripped of acetyldehyde by distillation.
adi54 - 25-3-2006 at 20:56
Thanks vulture & thanks garage chemist for replies what about aldol condensation with dil NaOH will it separate acetaldehyde as aldol
garage chemist - 26-3-2006 at 05:13
Yes it will seperate acetyldehyde as aldol. But you can't get acetaldehyde back from aldol.
adi54 - 27-3-2006 at 08:21
can I separate acetaldehyde as some useful salt or ppt.
Nicodem - 27-3-2006 at 10:42
Can't you just liquify the acetaldehyde&NOx mixture, throw it in some icy aqueous solution of sodium ascorbate (or other neutral to slightly basic
reducent) to absorb and destroy the NO and NO2 and distill out the acetaldehyde? You will have troubles condensing it though. Try with icy water in
the condenser or a CO2 cold trap.