Author Topic: "Wet" NP  (Read 2162 times)

0 Members and 1 Guest are viewing this topic.

place

  • Guest
"Wet" NP
« on: May 30, 2004, 12:42:00 AM »
SWIM did a extraction on some ephedrine pills.

Crushed the pills.
Boiled 3 times in Xylene/Ethylbenzene.
Boiled once in acetone.
Extracted 2 times with hot dry IPA.

If the yield was 100%, SWIM would get about 45g. E.

By huge mistake, SWIM forgot to dry the Xylene/Ethylbenzene which was used for the first boil. The Xylene/Ethylbenzene for the last two boils and the acetone was dried. And of'cause SWIM did first discovered the mistake after he had discard the first Xylene.

After the IPA from the two last alcohol extractions, SWIM only got 18g E, a 40% yield. If SWIM does one last IPA extraction, he migth get a few extra grams.

Now to the question, is it really posseble for the water in "undried" Xylene to steel so much E? Or does the E hide some where else?

TIA.   :)

Bandil

  • Guest
Shouldn't matter
« Reply #1 on: May 30, 2004, 03:03:00 PM »
That your xylene/ethylbenzene is somewhat wet, shouldn't matter much when doing that sort of work. I highly doubt that much of your product is hiding here.

I'd say that most of the lost product is due to insufficient IPA extraction. Try using more IPA or perhaps extract a few more times and see what that does for yields!

Regards
Bandil


place

  • Guest
More IPA?
« Reply #2 on: May 30, 2004, 03:39:00 PM »
The ammount of IPA for the first extraction was 500mL and the second about 300mL. 

Damn, E and IPA is quite a bitch! :)

When extracting, is it necessary to soak the pill mass for a while (that say 12-24 hours) or does the E jump over to the (hot)IPA in no time?

geezmeister

  • Guest
soaks not needed
« Reply #3 on: May 30, 2004, 05:49:00 PM »
Assuming you ground your pills very fine, long alcohol soaks are not necessary. Back in the day of the easy to extract pill when there were several brands that pulled well with MeOH, I extracted with three volumes of MeOH. I let the pills stand the first time for twenty minutes, the second for ten, and the last for five. Longer soaking only brought more inactives.

If you use IPA to extract, it needs to be hot, and when hot is a very good solvent for this purpose. I will extract with three volumes of IPA, bring each to boiling and hold it at or just below its boiling point for three to five minutes. Works for me.

Wet xylene is not the problem. I can't say whether wet ethyllbenzene might be involved, as I am not familiar with its characteristics, but would be surprised if that were responsible for the loss you describe.