Extraction of codeine from aspirin

[redeemer]

I tried posting this in Drug Basics but I didn't get much repsonse, probably because it isn't so basic. Well, I have some pills containing:

codeine phosphate hemihydrate: 9,6 mg
acetylsalicylic acid (aspirin): 500 mg
magnesium hydroxide: equivalent to 150 mg magnesium oxide

The reason a cold-water extraction won't work is because the magnesium from the magnesium hydroxide will react with the aspirin creating a very water soluble magnesium salt of aspirin. The procedure I use for getting rid of the aspirin is as follows:

Dissolve pills in approx. 4 mL water per pill. Cool to 5°C, filter off insolubles (this will be the binders etc. in the pills)
Add small portions of 30% HCl to the now filtrated pill solution. A white precipitate is seen falling out of the solution, cease addition of HCl when no more precipitate forms.
Filter off insoubles again (this should be the aspirin). I then neutralize the solution with Na2CO3 and the result is an almost clear solution with a slightly yellowish tint.

As far as I can see this procedure should work in theory, should it not?
I did this last night with 35 pills containing 350 mg codeine in total. It's hard to say how much of the solution was lost in the filters etc. but I'd say a yield of at least 80% was achieved, that's 280 mg codeine.

I ingested this last night and not much happpened really. Previously I have tried with 8 pills, then 16, 20, 30 and now 35 pills and I don't feel much of an effect. Maybe a tiny bit drowsy but this could just as well be placebo.

Is there a critial flaw in my preparation of the codeine or should I just try with more pills?

Thanks in advance,

-Redeemer

 

[protovack]

I'm a beginner at chemistry so I have a few questions:

What happens to the Magnesium Chloride formed when you add HCl?

Why neutralize with Na2CO3?

 

[TheDEA.org]

That's fairly clever. I wonder about the codeine solubility, though...perhaps pulverizing the pills and dissolving them in water is allowing the codeine to be freebased by the magnesium hydroxide, which might cause significant amounts of the codeine itself to precipitate out from the start (with the binders.)

If you are recovering the codeine by evaporating the solvent, the dry mass you're left with will of course include various salts, inflating the apparent yield.

Try acidifying and mixing well before filtering anything off. I'm not sure how soluble codeine freebase would be in, say, ether, but I'm guessing it's fairly good, in which case an extraction should be able to separate the codeine from the various ionic crap in the water.

 

[redeemer]

I wonder about the codeine solubility, though...perhaps pulverizing the pills and dissolving them in water is allowing the codeine to be freebased by the magnesium hydroxide, which might cause significant amounts of the codeine itself to precipitate out from the start (with the binders.)

That's exactly what I think has happened. I thought about it last night and that is what I came up with too, and according to my calculations, there is 2.8 mmol aspirin, 0.024 mmol codeine phosphate and 3.7 mmol Mg(OH)2 so the amount of magnesium hydroxide in the pills should be able to freebase the codeine.

I'm currently filtering the solution of 10 pills which has been acidified beforehand (about 1 mL 30% HCl per pill) and will report back what happens

I'm not sure how soluble codeine freebase would be in, say, ether, but I'm guessing it's fairly good, in which case an extraction should be able to separate the codeine from the various ionic crap in the water.

Previously I have tried seperating the codeine completely with a non-polar solvent but the inactive ingredient "hypromellose" in the pills helps to create a terrible emulsion. Apparently it is added to make extraction more difficult while also having an extended release effect.

What happens to the Magnesium Chloride formed when you add HCl?

It should be in solution.

Why neutralize with Na2CO3?

So I don't have to ingest a very acidic solution (pH <1). I'm not sure if it is acidic enough to cause any harm but I'm playing it safe .

 

[MegaManMX12]

( Does anyone have any suggestions for extracting acetylsalicylic acid (aspirin) and caffeine out instead of Aspirin and magnesium hydroxide? )

 

[redeemer]

^ Well here's what I found after a simple search here on Bluelight:

http://www.bluelight.ru/vb/showpost.php?p=3304296&postcount=6

The search engine is your friend.

 

[redeemer]

I did it. I tried the procedure where I crush up, dissolve the pills in water and acidify the water (with approx. 1 mL HCl per pill). I then filter off the insolubles, collect and neutralize the filtrate with Na2CO3 and ingest.

I did this with what should be around 140 mg codeine in total and I felt no effect. I'm not sure if the effects of codeine are that subtle or if I'm doing something wrong. Could the HCl possibly degrade the codeine? I have noticed when adding HCl and bit of white smoke leaves the solution. The smoke smells like HCl or maybe chlorine but I'm not sure.

 

[redeemer]

I just tried the same procedure with 30 pills which should be 300 mg codeine in theory. My stomach hurt a bit the first 20 minutes after ingesting the solution but it was probably because of all the salt and the citric acid I added.

I actually think I felt a little bit, very slight euphoria and the same lightheaded feeling I get when taking Kratom. I got very thirsty later on which probably was because of all the salt in the solution. About 4 hours after ingesting I also got a terrible case of diarrhea (which wasn't very recreational). I'm guessing it might have been the magnesium?

I'm going to post updates in this thread whenever I try a new method in hopes of someone better at chemistry than me explaining where the codeine goes, cause I simply can't figure it out!

 

[BilZ0r]

300mg of codeine would have me fucked out hard... You better have a big tolerancem or that extraction didn't work at all...

So are you going to try that linked (no acid) method next?

 

[redeemer]

Yeah, I know . And since I've never tried codeine before it must be the extraction that's the issue, but I simply can't figure out what I'm doing wrong.

As I see it the no-acid extraction wouldn't work in my case. The problem is the Mg(OH)2 will react with the aspirin and create a very water soluble salt of aspirin, so the way I figure it I have to add an acid to remove that Mg from the aspirin thereby reducing its water solubility greatly.

I'm thinking of using an acid that isn't as harsh as HCl, maybe citric or acetic acid or something similar. I just bought a big-ass jar with 250 pills so I should have enough to experiment on.

 

[BilZ0r]

Hmmm... MgOH is pretty insoluble though. You should try and find some pH strips, and find out.

 

[redeemer]

Yes, Mg(OH)2 is pretty insoluble in water with neutral pH, but in my pill solution it will react with the ASA (aspirin) creating water and MgASA. Though Merck says this salt should decompose quickly I don't know what it decomposes to and if it's safe to consume.

But yes, I need some pH-strips. I've tried measuring the pH with red cabbage juice but it's quite inconvenient and I'm not sure how accurate it is.

 

[redeemer]

I've recently acquired some narrow range pH sticks and a solution of 100 pills in 300 mL water was measured to 5.0-5.5. Would the codeine stay in solution at this pH? Or is that not solely related to pH?

 

[redeemer]

^ Thanks for the advice, I wasn't aware of the slow neutralization time of MgOH. If that wasn't the case though, wouldn't the MgOH just keep dissolving more and more as it neutralizes the ASA (because the magnesium ions are removed from the solution by the ASA) until all the MgOH has been dissolved?

I've measured the pH of the solution again today and now it has dropped to 4.5. Merck says this about ASA:

"Decomp by boiling water or when dissolved in solns of alkali hydroxides and carbonates. Inorganic salts of acetylsalicylic acid are soluble in water (esp the Ca salt, q.v.), but are decomposed quickly."

So I actually think I should wait a bit before filtering the solution as the MgASA will decompose thus lowering the pH, although I haven't measured the pH just after dissolving the pills so I'm not sure if the initial pH is low enough to justify filtering at this point. I'm not sure what the decompositon product is or if it's soluble in water though I can see something precipitating after letting the solution sit for a while so I know some of it isn't water soluble.

I'm quite certain that the contents of these pills has been designed to prevent a CWE from being carried out properly, I've heard people ingesting such CWEs complaining about stomach aches and tinnitus which are classic symptoms of ASA poisoning.