Author Topic: Purifying Methylamine  (Read 1620 times)

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jaws

  • Guest
Purifying Methylamine
« on: November 13, 2002, 03:11:00 PM »
Is there any other way to purify methylamine than with 190 proof vodka?
Jaws can only get 153 proof where he lives. could he just distill this?? :-[
He's heard of acetone wash but he doesn't think that this will remove the ammonium chloride. :(

goiterjoe

  • Guest
methanol
« Reply #1 on: November 13, 2002, 04:22:00 PM »
IIRC, ammonium chloride isn't very soluble in methanol, so you could use this to extract the methylamine salt.

If at first you don't succeed, try, try again. Then give up. There's no use being a fool about it.

terbium

  • Guest
Convert to gas.
« Reply #2 on: November 13, 2002, 07:35:00 PM »
Do you have a pH meter so that you can perform a titration to determine the ratio of ammonia to methylamine? If so then you can get rid of the ammonia by adding the requisite amount of sodium hydroxide to an aqueous solution of the crude methylamine/ammonia salt in order to selectively convert the ammonia chloride to ammonia. The solution could then be boiled to drive off the ammonia leaving behind a solution of methylamine.HCl and some salt.

Baseline Does Not Exist.

jaws

  • Guest
methanol??
« Reply #3 on: November 21, 2002, 07:49:00 PM »
So can jaws just disolve his methylamine HCI in some methanol filter out the undisolved ammonium chloride and then just put it in the freezer to get his methylamine crystals back???

Chromic

  • Guest
Read RB's writeup
« Reply #4 on: November 21, 2002, 10:04:00 PM »
RoundBottom performed my suggested work up and wrote about it. Basically you add your impure MeAm.HCl to a flask, then add a bit of MeOH... bring it to a boil, and slowly add more until most of the solids have dissolved. Then pour it off into a beaker, slowly cool the beaker (undisturbed). Move to your freezer, get nice plates (is that the word? heh, just look at the pic) of MeAm.HCl, then filter, cover in cold dry acetone and filter again. Dry on a gentle heat in a room with no humidity. The crystals look amazing when done.

Of course, when you're finished this synthesis, and I hope you live in a country where such work is legal, you can then promptly flush them down the toilet. You'll be surprised how water soluble these crystals are. If you rub them between your fingers, they will dissolve and turn your fingers a rosy red color. I don't recommend that you try that test too many times. :)


RoundBottom

  • Guest
simply
« Reply #5 on: November 22, 2002, 12:20:00 AM »
yes.  but let it recrystalize slowly, not straight to the freezer, you will retain some impurites if you do it that way.

Now with 12% more Bottom!
Nymphomania is not a disease, its a goal! (Methadist)

jaws

  • Guest
love the pics
« Reply #6 on: November 22, 2002, 02:20:00 PM »
Thanks for all the info and Jaws really loves the pics. :)