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Codeine and Caffeine

rave23

rave23

Bluelighter
Joined
Feb 17, 2007
Messages
1,844
Location
Canada / Germany
Hello Folks,

i thought i ask in advanced drug discussion what the best method is to extract the caffeine from codeine.
There are several methods out there, but i found none to work. So i'd like to give it a more 'professional' try than just kitchen chemistry.

What would be the most desirable way to remove or at least reduce the amount of caffeine from a solution of both codeine and caffeine?

Could one evaporate the solution and utilize the different solubility of both substances in some solvents to either dissolve the caffeine or the codeine, and separate both substances?
Maybe the codeine is soluble at much lower temperature, not allowing the caffeine to dissolve and to stay solid in solution?

Any thoughts and ideas appreciated, i know there are a lot of smart folks around here. Thanks for helping me out.
 
Do you have access to more profession equipment and have the skills? Otherwise, there's no point.
 
i do have no access to a lab. I do not have access to advanced chemical equipment. I do have limited lab skills.

I'd like to hear a possible way anyway. I didn't say i was actually going to do it. i just wanted to learn more about possible ways of extracting it.
 
Well, it's possible. But is it possible without quality skills and equipment and chems hard to get without a business account? Probably not.
 
cold water extraction requires exactly what beyond cold water and patience?

ps-this is ADD people
 
kidamnesiac, if you would read my post you would know that i want to separate the caffeine from the codeine in solution which is not done by a simple CWE. This is not easy and indeed ADD. If you know how to then i'd like to hear your suggestions.

Ham-milton: Yes, i know that. I am just interested in the principle. I know i am not capable of doing that stuff in my kitchen, and i don't want to. I am simply interested in the abstract. I know that it's somehow possible, i'd just like to know how! On what theories and or mechanisms is this extraction based?
 
kidamnesiac said:
cold water extraction requires exactly what beyond cold water and patience?

ps-this is ADD people
Click to expand...

Since when can you seperate two water soluble's with a CWE?
 
Mr Blonde said:
I thought he got the impression they were in tablet form still...and that you weren't concerned with all the aspirin and shit, lol

Anyway by using Google:

According to this page, caffeine is only slightly soluble in benzene.

And according to this page, codeine is fairly soluble in cold benzene.

And according to here, benzene ain't too good for your health.

So yeah, it could be done, but no way would it be worth the effort and risk required.
Click to expand...

substitute toluene for benzene and experiment....
 
oh god, THANK YOU GUYS. That was all i was looking for. Now i got my pieces of information, and am a happy bluelighter :) Thanks.

Bam and close, i think we're done here.
 
meh *shrugs shoulders*, i am not really interested in extracting pure codeine, even though you could do some mighty nifty stuff with it. I guess i drop a line in my notebook, and if the need should arise at any time i have something to refer too.
If i can dig out some pyridine and hydrochloric acid things could be fun. But again, i really don't need too.
 
caffeine:
22 mg·mL−1 (25 °C)
80 mg·mL−1 (80 °C)
670 mg·mL−1 (100 °C)

codeine:
1g / 2.3 ml (31C)
1g / 0.7 ml (21C)

so at around 21 C (NOT very cold) you can get ~1.5g (A LOT) of codeine in a mL while you would have 22mg (1/4 a can of coke) caffiene. what do you think happens when you go colder?

don't believe every dumb-ass opiate faq you read.

values taken from wiki for caffiene and opiates.org for codeine.
 
mhhhh i kinda noticed that, if i throw the liquid in an ice bath and cool it down to about 1°C there is a lot more stuff falling out the solution that seems clear at 15°C. I always thought there has to be some caffeine, but i thought most of it was additional aspirin. Now that you notice it there are actuall slight differences in the 'feel' of ice-filtered codeine. This might be because of lower caffeine level?

I conducted a small and simple experiment. I took 200mg caffeine each, and poured equal amounts of caffeine in 2 x 5ml @ 21°C and 1°C testtubes, while the stuff almost immediately dissolved in the 21°C it seemed to do hardly anything in the 1°C. A test of the taste confirmed that, while the first solution had the standard-caffeine-bitter-taste the 2nd one had nothing. The caffeine seemed to be completlely disolved when heating and stirring the tube to 8°C

I guess it's all about filtering the pills as cold as possible with as little watter as possible.

What concerns me though is the solubility of codeine. If the decline in solubility is somewhat linear there won't dissolve a lot of it in ice-water. Screw that. What are posibilities of destroying, damaging or altering certain molecules? Could one modify the caffeine only and maybe render it into an inactive compound? Is that even possible?
 
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there are only two data points to draw a conclusion from, but it looks to me like codeines solubility increases with decreasing temperatures...probably plateaus around~4C but that aint bad
 
The best method...

.. if you have the wherewithal to do chromatography, is to do TLC experiments until you find a solvent pair that gives good separation, then just do a "plug column" with a short plug of siiica gel or alumina or whatever solid phase you found worked the best.
 
It looks like the wiki info on caffeine solubility may refer to the freebase, i imagine the salt is much more soluble than that, as Rave seems to have found.

You could maybe exploit the differences in bascisity between the two. The weakly basic imidazole in caffeine would have a pKa close to 7, while the tertiary amine in codeine would have a pKa close to 11.

So dissolving them in water with a pH of 9 would mean that 1 in 100 caffeine molecules would be in the form of a salt, while 1 in 100 codeine molecules would be in the form of the freebase. Therefore the caffeine would be mostly in the sparingly soluble freebase form while the codeine would be in the soluble salt form. This should allow precipitation of most of the caffeine. (If i remember pKa's right, i hate that stuff!)

http://www.changbioscience.com/calculator/HendersonHasselbach.html

Yeah this confirms it, pick the acid or base, type in the ratio of salt to free acid or base you want and it tells you the pH of the solution.
 
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