Author Topic: ethanol evap gives weird yield  (Read 2232 times)

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12cheman12

  • Guest
ethanol evap gives weird yield
« on: August 03, 2004, 09:04:00 AM »
Swim has been fucking with alot of pills as of lately (Oz Pills).
His plan was to let the PM soak in a dcm/perch mix for a couple of hours, extract with ethanol, evap, dissolve whats left in water and add a basic solution to this water to give the freebase and then pull the freebase with a NP.
Evap the NP and do some SPD on the FB.

Well what has been happening is, he would dissolve his pill mass in alky, filter this alky and evap, when he evaps it gives NO formation of any kind... looks like nothing is their and you'd be forgiven if you thought there was nothing their at all but their is something there you just cant see it because it looks like a sheet of glass.
Anyways swim would then dissolve this in water (the water tasted STRONGLY of pseudo so he knows its in their) and his attempts to bring the freebase out have all been unsuccessful. No matter how high the PH is risen the freebase wont come out.
If a NP is added and shaken up it creates these physical objects that suspend themself in the NP (must be holding his FB) and then dissolves back in after a few minutes.

The NP is evaped and only got back less then a point of FB.

Swim is guessing this shit is holding his FB in his water.

He has only seen this problem of the freebase not coming out of the water when the pseudo evaps from the alky like stated above.

Does anyone know what this could be or seen something like this before?


p2e3r4f5e6c7t8

  • Guest
Crashing
« Reply #1 on: August 04, 2004, 04:02:00 PM »
Has swim tried acetone crashing ?


geezmeister

  • Guest
sticky?
« Reply #2 on: August 04, 2004, 06:44:00 PM »
Is your solution after evaporating the alcohol sticky to the touch?

I've seen that a number of times. That could be any of several gakks. It could be PEG, or hypromellose, or one of the newer polymers, or a mix of them. When you have a polymer with the pseudo that impedes crystal formation, you will probably find acetone flashing to be of little help. Some of these gakks are soluble in acetone, and pseudo HCl is fairly soluble in the gakky acetone.

One approach to cleaning the pseudo is to dissolve it in 91% IPA and follow Fester's hydrolysis method using KOH to clean the pseudo. This works.

Another alternative is to do a MEK flash of the dried pseudo. Put the evap dish under a heat lamp, in the sun on a hot dry day, in an attic, or on low heat in an oven-- whatever it takes to give you a warm, very dry environment. Dry the pseudo mixture completely dry. As it dries, crystals will form in the gel. Keep drying. Dry until the pseudo is cloudy and whitish/yellowish. It will no longer be clear. You do not want any clear areas left or any area that feels sticky or oily. Bake the gel dry. This doesn't require high heat. It takes a little patience. 

When the pseudo is very dry, and while the pan is still very warm (you should alomost need a hot pad to hold it) flash with an excess of MEK. (Yes, dry the MEK first.) Use enough MEK to cover the pseudo to a depth of 4-5 mm or even a little more. Rock the pan, moving the MEK around in it, washing the pseudo loose from the glass.  Use a gloved finger or a spatula or razor blade to loosen any  pseudo stuck to the glass. Mash up any clumps. The MEK will pull a yellow color from the pseudo, leaving white flakes of pseudo. Pan the pseudo to a corner of the pan and decant the MEK. Add fresh MEK deep enough to cover the pseudo, put it on low heat and allow it to simmer with a little stirring and mashing for five to ten minutes. No need to boil the MEK. Pan the pseudo to a corner of the pan and decant the MEK.

If you use acetone rather than MEK, you will get a little clean pseudo, but most of the yield will dissolve in the gakked acetone again. For some reason pseudo doesn't seem to dissolve in gakky MEK the way it will in gakky acetone. After the MEK rinse, try to recrystallize the pseudo. It should recrystallize now. You don't want to react pseudo that won't recrystallize.

You could also do a "xylene clean." Dissolve the pseudo in alcohol, filter the solution, then precipitate the pseudo in a mixture of xylene and naptha by heating to boil off the alcohol. Filter the precipitated pseudo out of the solvent while the solvent is still hot. Do not wait. Take it off the hotplate and pour it through a filter right then. Rinse immediately with MEK. The pseudo precip technique using xylene and naptha does a good job on PEG. The xylene helps if polysorbate 80 or hypromellose is the contaminant. Filtering while the solvent is still hot is the key to the cleaning method. If the solvent cools even a few degrees other substances will precipitate in the solvent, and you will filter these out with the pseudo.

None of these methods replaces the cleaning done by dual solvent recrystallization. You may need one of them to get the pseudo clean enough to recrystallize.

Give the MEK a try. It costs more than acetone and stinks like hell, but what works, works. And that is what counts here. It won't solve all your problems, but it may solve some of them.


p2e3r4f5e6c7t8

  • Guest
You the man geez
« Reply #3 on: August 04, 2004, 11:15:00 PM »
Nice advice GEEZ ;)
Swip stands's corrected :P


12cheman12

  • Guest
its pseudo sulfate...
« Reply #4 on: August 05, 2004, 02:54:00 PM »
its pseudo sulfate...
when the alky is semi dry it is gooey to touch, almost like chewing gum but a clear colour.
If left under heat to complety dry it becomes rock hard, looks like a perfect sheet of glass, u cant even tell anything is their...
Will take geez advice n give it a shot, thanks mate ;)


geezmeister

  • Guest
a/b it first
« Reply #5 on: August 05, 2004, 04:26:00 PM »
A/b it first. Freebase the pseudo sulfate then titrate it for the HCl form. You don't want to react the sulfate form anyway. You are likely having problems with the ethanol evap in part because of the sulfate form. What I mentioned above helps with pseudo HCl. I've not extracted from any pills containing pseudo sulfate in some time now, and my comments may not be good for that form.


12cheman12

  • Guest
yeah thats the problem, A/Bing isnt working,...
« Reply #6 on: August 06, 2004, 06:32:00 AM »
yeah thats the problem, A/Bing isnt working, the pseudo STAYS in the water.
I think if i somehow force the pseudo out of ethanol before the a/b, crashing with acetone or boiling the ethanol out of xylene and making the pseudo precip out then an a/b might work...


p2e3r4f5e6c7t8

  • Guest
how's the progres going
« Reply #7 on: August 09, 2004, 11:18:00 PM »
How is swim going with that psuedo that stays in the water layer 12cheman12 ?
Any luck yet or any good news on your progress ?


geezmeister

  • Guest
Won't base?
« Reply #8 on: August 10, 2004, 05:38:00 AM »
The pseudo won't base? Period? Evap the water undser a fan. Don't use heat, if you do have freebase pseudo in the water you will evap a lot of it off if you use heat. Once you have it dry, follow Fester's suggestion in the deconstuctionist thought thread. When you get through there, you will have freebase pseudo.