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recrystallization problems

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washerguy

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Joined
May 12, 2015
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13
washed product in acetone then followed the process with isopropyl and added a few drops of acetone. Final product is very white and powdery even though it's stuck together. How do I get better crystals?
 
Should I add water? I also put it on ice. It Is literally just like loosely rocked blow
 
It sounds like you don't even understand what recrystallization is. Maybe state what you are actually trying to recrystallize and what procedure you are using because what you have posted is beyond vague. Why would you even consider adding water?
 
what are you recrystallizing? cocaine?

an acetone wash is not a recrystallization. and as far as i knew cocaine is soluble in isopropyl alcohol(!!!).

putting water in cocaine is a no-no. you'll destroy it and turn it to benzoylecgonine = inactive as a stimulant.

if it's the hydrochloride salt I have no fucking clue how you'd grow a crystal aside from really slow precipitation from alcohol-hexane maybe?
 
sorry I should have been more specific. my friend has been getting some pretty cut methamphetamine recently and I did the research and was trying to purify it. so first obviously I did the acetone wash which helped a good bit but wanted to purify even more. so I used isopropyl alcohol heated it to boil then mixed it in until I covered the product and put that to a boil took it off and then a couple drops of acetone in it after it came to a boil and swished it around. It became clear. As soon as crystals started i put it on ice still in solution. Put it on ice about 10 minutes later. Waited 12 hours or so and it was stuck together but with the consistency and look of almost like cocainE. It had dirty stuff ok outside so I just did another acetone wash. How do I recrystalize it to look like it is supposed too?
 
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Sorry. It's meth. Washed w aceton . Recrystallization w isopropyl alcohol. Turned into something that looked like loosely rocked coke and was Flaky.
 
I need a lot of advice

sekio said:
what are you recrystallizing? cocaine?

an acetone wash is not a recrystallization. and as far as i knew cocaine is soluble in isopropyl alcohol(!!!).

putting water in cocaine is a no-no. you'll destroy it and turn it to benzoylecgonine = inactive as a stimulant.

if it's the hydrochloride salt I have no fucking clue how you'd grow a crystal aside from really slow precipitation from alcohol-hexane maybe?
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It's meth and I used isopropyl for recrystallization and acetone for washes
 
Basically I'm ready to try it again now. It was still good quality just not what I expected. I'm wanting it to look like it usually does.
 
washerguy said:
Sorry. It's meth. Washed w aceton . Recrystallization w isopropyl alcohol. Turned into something that looked like loosely rocked coke and was Flaky.
Click to expand...

You filtered the product recovered from the cold IPA right? I'm assuming your acetone is dry, is your IPA anhydrous or does it contain some water? Most drug store IPA is 91% at most. If you have a significant amount of water, it is going to make a difference. Does what you have recovered smell like solvent still? Sometimes certain solvents like IPA, ethyl acetate, etc can be much slower to evaporate than would be expected. It's also possible you are using too much IPA. What volume of IPA are you using to what volume of product?

Honestly, if you are dissolving your stuff in boiling IPA/acetone and filtering out the solids that crash out of solution the stuff should getting cleaned up very nicely. Pure powder is just as good as pure crystals. If you really concerned about growing nice crystals you might try something like this:

1.) Add to 4-6x volume of acetone (I'd use 4) and bring to a boil. Solids should not completely dissolve. In a separate flask bring some anhydrous IPA to a boil at the same time.

2.) Slowly pipette boiling IPA into the flask containing acetone/compound. Continue adding until it dissolves. Toss this in a fridge and leave overnight or longer. Filter off the solvent and let the collected solids dry.

3.) Make sure to keep the mother liquor. Add another 4 volumes of acetone to this and toss it in a freezer. Very likely you will get more precipitate. Collect this also :)

This is just my recommendation. Honestly it sounds like you've probably purified it as is and further recrystallization is going to result in some degree of loss. I'd honestly leave it as you have it, but if you don't mind losing some and want to experiment a bit go for it. Recrystallization takes some practice especially if you haven't done it before. Different solvent systems and techniques can give widely varying results, even for identical compounds.
 
Thanks. Yes it was dry acetone and
99.9 percent isopropyl. I think I just used too much alcohol and cooled it too fast. I just got done with my 2nd try. Well see.
 
pr0d1gy said:
You filtered the product recovered from the cold IPA right? ----Yes i filtered -- when should I filter after ipa process? - I'm assuming your acetone is dry, is your IPA anhydrous or does it contain some water? --Yes its 99.9 percent -- Most drug store IPA is 91% at most. If you have a significant amount of water, it is going to make a difference. Does what you have recovered smell like solvent still? --no--Sometimes certain solvents like IPA, ethyl acetate, etc can be much slower to evaporate than would be expected. It's also possible you are using too much IPA. What volume of IPA are you using to what volume of product? --I think that was the problem. I used much less this time and it looks like it is starting out great--

Honestly, if you are dissolving your stuff in boiling IPA/acetone and filtering out the solids that crash out of solution the stuff should getting cleaned up very nicely. Pure powder is just as good as pure crystals. If you really concerned about growing nice crystals you might try something like this:

1.) Add to 4-6x volume of acetone (I'd use 4) and bring to a boil. Solids should not completely dissolve. In a separate flask bring some anhydrous IPA to a boil at the same time.

2.) Slowly pipette boiling IPA into the flask containing acetone/compound. Continue adding until it dissolves. Toss this in a fridge and leave overnight or longer. Filter off the solvent and let the collected solids dry.

3.) Make sure to keep the mother liquor. Add another 4 volumes of acetone to this and toss it in a freezer. Very likely you will get more precipitate. Collect this also :)

This is just my recommendation. Honestly it sounds like you've probably purified it as is and further recrystallization is going to result in some degree of loss. I'd honestly leave it as you have it, but if you don't mind losing some and want to experiment a bit go for it. Recrystallization takes some practice especially if you haven't done it before. Different solvent systems and techniques can give widely varying results, even for identical compounds.
Click to expand...
--I'm hoping I can get crystals from just the ipa- my friend needs it to be marketable so powder is not Ideal. --
 
So it looks like it worked well this time clear etc...still some isopropyl would love to leave it sitting for a week but that'd not possible. What are next steps
 
washerguy said:
So it looks like it worked well this time clear etc...still some isopropyl would love to leave it sitting for a week but that'd not possible. What are next steps
Click to expand...

Did you just use IPA or did you do it with acetone and the bare minimum of hot IPA? You should leave it on an open surface like a recrystallizing dish or glass plate with good airflow over the surface. Maybe have a small fan blowing over it. Another possibility would be to put it under a lamp. Without a rotovape or vacuum pump it may take a while. Give it a day or two.
 
I washed it with acetone then recrystailed it with boiling hot 99.9 iso. It is just sitting in iso still. What do I do? What do I do when dry? It worked tons of small beautiful crystals.
 
filter off the crystals (decant/coffee filter), keep the mother liquor in an open container at r.t. and let it evaporate, will produce more crystals as the iso evaporates

keep the xtals in a sealed container in a cool dry place
 
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