Hello Everyone. I'm trying to remove the ammonium hydroxide (BP 37.7) residues from some DCM (B.P. 40) that I have sitting around. The question is whether these two form an azeotrope - I've searched everywhere and found almost nothing on this - and whether there is some other process I should consider before going to the ol' vigreaux.

 

any help would be greatly appreciated!

 

cheers

 

Jeff

I should just wash it out with some dilute HCl and then water. Dry the DCM with a basic drying agent after

thanks tartaglia, I'll give that a try!

ammonium hydroxide does not exist. But yes, what tartaglia said would be my guess too.

I'm washing with a 10% HCl solution, just wanted to make sure I'm not overdoing it.

and for these washes, what is the ideal ratio of product/solution?

thanks again for your help.

Edited February 5, 201015 yr by JMiller

not sure what you mean by product/solution ratio. However, you can tell if you're overdoing it by first deciding exactly what "overdoing it" would entail (perhaps it doesn't matter if your solution is acidic anyway?) and then using a pH paper to test a drop at a time. If the solution is only slightly acidic or basic, a few good washes with water will get it closer to neutral, if that's what you desire.

actually, it doesn't really matter if the solution is a bit acidic, so that answers that. I seems that I still need to learn to think a step or two ahead.

final question (now that you're being so helpful!): I'm using the DCM for extractions. knowing that drying the DCM with a drying agent will not completely remove the 98:2 H20 azeotrope that was formed, will this "impurity" affect the extraction process?