What causes waxy methamphetamine?

[qwe111]

I have done isomer separation! I have successfully crystallized in water before and obtained beautiful crystals!
I used the same method, but I got a strange product this time! I don’t know what I did wrong?
Can you tell me what I should do to make it crystallize normally?
Should I re-extract the methamphetamine FB and do it again? Or crystallize it in other solvents?
Thank you very much!!!

 

[Pororo]

i don't know what separation route you used, but probably not acetone.
did you try this? prepare the flask, turn your meth into powder as fine as possible and throw it in anhydrous acetone in the flask. use around 5 ml of acetone per 1 gram. use water bath above 50 but below 55 c, and heat the flask while stirring it.
cool it down to rt, then move to a refregerator for a few hours, then move to the fridge for 12-24 hours
check the result.

if not work, repeat all the steps but add some water, depends on purity 5-10% of meth weight.

 

[qwe111]

Hi Sir, I used L-tartaric acid route to separate isomers!
I have not tried crystallization in acetone, I am a beginner and have only done recrystallization in water in small batches.
I successfully obtained very beautiful crystals when testing.
Now the methamphetamine and water are mixed together, should I use sodium hydroxide to extract the methamphetamine oil, use hydrogen chloride gas to obtain the hydrochloride and then recrystallize in acetone?
Or should I use this waxy methamphetamine directly?

 

[Pororo]

can you describe step by step what you did with what reagents and solvents from the beginning (when you added L-tartaric acid) till the end (when you got oily crystals)?

may be i try to answer something.

if L-tartaric was used disregards my message about acetone: your problem is more complicated.

 

[qwe111]

Sorry sir!
I dissolved L+ tartaric acid in water, then added methamphetamine oil, stirred until solid was obtained, and then vacuum filtered the tartaric acid methamphetamine mixture after leaving it for 24 hours.
The obtained liquid part was added with sodium hydroxide solution to extract D-meth.
Then precipitate methamphetamine hydrochloride using hydrogen chloride gas.
Dissolve methamphetamine hydrochloride in distilled water 1:1, heat to 108 degrees, and wait for crystallization!
The previous test was normal,
but this time I got this waxy crystal.
I searched all the information on the forum, and some people said it was because methamphetamine is racemic.
There are also people who say pH value, I measured the pH value, about 5.
Another question is that when measuring the pH value, drop the liquid onto the test paper, and the liquid will have 3 different colors after diffusion. The outermost color is about 10, the second layer is 5-6, and the first layer is 1-2.
I am at a loss, I have no professional knowledge and I don't understand chemistry.
I just dissolved a small portion of waxy methamphetamine and extracted methamphetamine oil with sodium hydroxide, and I am doing it again.
Because I feel that no one will give me an answer.
Anyway, thank you

 

[Pororo]

was it dirty meth oil or distilled? there could be some colloid inside. opposite isomer also can be trapped.

before you turn rest of you stuff to the base do following:

prepare the flask, turn your meth into powder as fine as possible and throw it in acetone (99% grade ok) in the flask.
use 5 up to 10 ml of acetone per 1 gram. prepare water bath above 50 but below 55 c, and heat the flask on water bath while stirring it, also slowly add some water. control water weight it is important!!! don't add more than 20 gr of water for 100 gr of your salt.
let it cool down to rt.
move to the refrigerator for a few hours, then to the freezer.

after that i would do base extraction, base will be pretty pure this time. and acidify with l-tartaric again. better use d tartaric if you can get it.

 

[qwe111]

There is no distillation. When separating isomers, it should not be too dirty after acid-base extraction.
I guess it may be a pH problem.
What should be the correct pH of methamphetamine aqueous solution?
Thank you very much!

 

[qwe111]

Because I was in a hurry, I tried to extract the base and adjust the pH value to <3 with hydrochloric acid. Heat to 130 degrees and pour 5 times the volume of acetone. And wash the powder with frozen acetone. After drying, dissolve it in water 1:1, heat and evaporate and cool. The methamphetamine on the thermometer is still the same waxy crystal after cooling. No crystals precipitated in the beaker after complete cooling.

Two other parts from different batches already have beautiful crystals!

I don't have the ability to judge what went wrong.
I will test your method tomorrow!
Thank you very much, sir

 

[Pororo]

one more detail

control water weight it is important!!! don't add more than 20 gr of water for 100 gr of your salt.

i mean, you add water in the flask slowly until all meth is dissolved. BUT don't add more than 20 gr of water per 100 gr of meth. NEVER!!! if you still see something solids on the bottom of the flask at this point, i bet it is not meth, it is sodium chloride.

 

[qwe111]

@G.Patton

Sir, help me! Thank you very much

 

[ByHyde]

 

[ByHyde]

My lower purity racemic crystal appears to have the same form as the crystal type in the experiment. How long does it take to melt and freeze inside the pipe? Can you compare it with Ice D and give information?

 

[qwe111]

It looks like there are some similarities, and the answer I found on the forum is also because of racemization!
But I remember doing isomer separation myself.
I'm not in the studio now. Maybe I can give you an answer in a couple of days.

 

[Pororo]

colloid was formed and you trapped your "bad" isomer in it.

 

[qwe111]

You are right, I put the extracted meth oil in the refrigerator to cool it down today, and then some floating substances appeared at the bottom of the beaker, I think it should be the colloid you said.
I will extract the oil according to your method.
I can tell you the results in a few days. I need to buy some things.
Thank you sir

 

[qwe111]

You are right, I put the extracted meth oil in the refrigerator to cool it down today, and then some floating substances appeared at the bottom of the beaker, I think it should be the colloid you said.
I will extract the oil according to your method.
I can tell you the results in a few days. I need to buy some things.
Thank you sir