This is what I would do:
* I guess the methadone hydrochloride concentration in that orange juice solution is pretty low. Hence, the first thing to do is to evaporate most of the solvent in order to obtain a more concentrated solution.
* Then add an excess of 20 % NaOH (aq.) to the orange juice. Don't drink this stuff, you will be sorry
.
* Now, extract the liberated free base with ether. Repeat this step several times. Dry the combined extracts over MgSO4 & filter of the MgSO4. Take the filtrate & pass a steam of HCl (g) through it. I think the crude methadone HCl will fall out of the solution (place the flask in the fridge). Collect the crystalls by filtration (if you don't obtain crystalls, just evaporate the ether).
* Recrystallize the methadone HCl in ethanol.
Cyrax is leaving the Hive (for safety reasons). I 'd want to say goodbye to all the fine bees I 've known here. I 'll probably return (under a new username) when the storm passes over ... The bees I 've known personally, will be informed about my comeback through PM.
Take care, dear friends.
Cyrax out //