Extraction of caffeine from tea or coffee!

Caffeine is found both in tea and coffee, IIRC to a greater extent in tea per gram of material.

The method of extraction depends on its solubility in chloroform, CHCl3.
The extraction from tea is preferred as emulsions form less readily, and as there are less coloured impurities.

Protocol:
1. Weigh out 50 g tea, or coffee (roast ground), or 20 g of instant coffee, and warm in a beaker with 200 ml H2O.
2. Boil this gently for 15 minutes.
3. Remove solids by filtering, and wash with a little hot H2O.
4. Heat the filtrate to boiling, and add 100 ml of 0.3 M lead II acetate (have a look at the PbO2 thread for details) in order to precipitate organic acids and proteins such as albumin.
5. Filter a small sample of this, and take the clear filtrate, and add lead acetate once again - this step is done to ensure that all has been precipitated.
6. Filter the whole filtrate, and add 2 M sulphuric acid to the filtrate to precipate the lead acetate (forming PbSO4). Filter this again.
7. Add 2 M ammonia (or whatever concentration you have) until it is at neutral pH, and then boil down to 100 ml.
8. Allow to cool a little, and add 5 g of decolorising charcoal and bring to boil again. Filter as before to remove the coal.
9. Add one portion of CHCl3 (40 ml) , and invert frequently (even better is to put it on rollers), rather than shaking, to avoid emulsification.
10. Repeat 9.
11. Add Na2SO4 (anhydrous) to the combined chloroform extract to remove traces of water, then filter.
12. Distill off the trichloromethane (waterbath), then evaporate to dryness. Dont do this in the house, do it outside. Recrystallise from hot water.

Yield : about 1 gram. A single cup of coffee contains about 110 mg (less in instant coffee, more in freshly ground coffee http://www.cspinet.org/new/cafchart.htm ).
Don't forget, this is a HUGE yield considering the original mass (50g) for a biological product!


Notes:
Instead of the chloroform, I am sure trichloroethylene can be used, which is a common solvent in hardware stores.
This procedure can be upscaled of course. Just get i.e. 500 g of tea, or coffee, and you will get about 10 g of caffeine. Enough to keep you energised for a while - not that I am suggesting to eat this (thats my disclaimer)
In this prep, I wouldnt be worried about the lead, because it doesnt dissolve in the chloroform/trichloroethylene. Not even a nanogram. Plus, if you do the recrystallisation as advised, you will remove any of the chlorinated solvents themselves by the recrystallisation procedure (chloroform/trichloroethylene are not soluble in water). In addition, a bit of heat evaporates these.
Although I am sure there are ways to poison yourself with it, I am equally sure if you follow the procedure there won't be a problem. That is, if you don't eat a gram of caffeine to test its effects (always start with very little, i.e. 100 mg in this case).

I am not trying to turn this into some drug discussion at all, I just felt there may be some individuals who are more than willing to test this with some rather excessive amounts

Sounds easier than a extraction with supercritical CO2 at least....

But for what good should the extracted coffeine be?

Hm, what about cannabinol extraction from low-THC hemp? This cannabinol is of course not psychoactive but damned legal.
At least until one converts it to THC-9 with EtOH and H2SO4.......
....what nobody would do of course.
Because its not legal.

ORG

One option is to eat it
Or, if you are into heterocyclic chemistry, you can use this as a precursor for more heterocyclics...you can nitrate it, acetlylate it, whatever you wish
But most importantly you can say: I know how to extract caffeine, here I got a few grams! Just like this silly pride you feel when you first time ever make a tetraamine complex, and the colour deepens... there is no direct use for it, still its cool!

Disgard the cafein and keep the now clean tea or coffie....
You can then prepare and drink homemade cafeinfree tea or coffie

JUST KIDDING FOR THOSE WHO THINK I'M SERIOUS ABOUT THIS.

[Edited on 1-7-2004 by PHILOU Zrealone]

for a minute..... I was wondering...

Oh, and Org,.. it is possible to extract THC from the leaves... with acetone it worked nicely. Left a nice sticky mass.. that had a very characteristical smell to it. Needless to say, that was a proof of principle only

Just a try to have cafein jpeg

And now THC...
great I didn't notice yet it was possible to make attachements..this will help a lot....

There is no reason for aceton to react since cannabisol (-binol) doesn't contain any amine group...it is one of the few psychoactive molecule that doesn't have an amine (nitrogen atom).

[Edited on 6-7-2004 by PHILOU Zrealone]

Organic molecules can dissolve in organic solvents with an appropriate ligand. Add a crown ether (of the form (-CH₂ CH₂O-)_n and you can dissolve damn near any metal salt in a nonpolar solvent. Any molecule with exposed lone pairs like that will probably carry a metal ion into solution. Could anything like that be present in the mixture of chemicals that make up coffee?

I’m guessing that a secondary purpose of the sulfuric acid is for the protons to bind to any such ligands and release the lead as free cations, aside from the obvious precipitation.