Advice on Separating Pseudoephedrine / Red #40

[SpectreOfCommunism]

I'll make this short -- the usual "wash with acetone until red color is gone" procedure does NOT seem to work with Sudafed (or at least generic SudaGest) 30mg pills anymore. The red coating is not iron oxide, rather it is Red #40 Aluminum Lake, which I can personally tell you is not particularly soluble in acetone. It IS soluble in both water and anhydrous ethanol, although it is not supposed to be -- according to my research, it should only be soluble in dry EtOH at 0.001g/100ml. In practice, however, it is soluble enough in dry EtOH that my pseudoephedrine hcl crystals are all reddish pink.

Anyways, bottom line is that I have a ton of PE hydrochloride crystals that are all contaminated with this stuff and I am having a hard time separating them -- does anyone have any experience with this? Or alternatively, does anyone have any experience with Red #40 contamination and the Moscow route (I2 + red phosphorous) reduction and will it gunk up my final product?

 

[MadHatter]

Shake the pills in shaved ice first. It mechanically removes the bulk of the red layer.

 

[G.Patton]

Probably it is just dye

 

[SpectreOfCommunism]

Update: After a few pills in a few test tubes with a few test solutions, I've found that a bit of methanol with 0.5% acetic acid seems to remove the red layer nicely (~2min of agitation) and then, after throwing the de-coated pill into a mesh strainer, the methanol evaporates quickly enough to leave the solid white pill-core intact. I'm sure a very small amount of the PSE gets lost (since its also soluble in MeOH) but I think it's probably about the same (or possibly better) outcome as removing the layer mechanically. Although the red is gone, I can still make out the imprinted numbers on the brittle pill-core and I take that as evidence that very little pill material was removed.

Ironically, this procedure relies on the binders and "gunk" to protect most of the PSE from dissolving in the methanol/acetic acid solution. Anyway, if anyone has any other ideas for how to improve the washing procedure, feel free to drop them here thanks

 

[G.Patton]

I think you lose negligently small part of PSE by reason that active substance is located under tablet shell

 

[Sonnettales]

I know this is an old post but I thought I would comment anyhow since I recently had the same issue. If you have a bunch of pseudo already contaminated with that pink color because you followed the “extraction from pills” #2 method on another forum here, the only thing I could do after that is an acid/base wash. Followed by a couple diethyl ether and washes and then one acetone wash. Had my crystals white as get all. On another note, in that other forum, the #1 method that uses activated carbon and Naptha gave my some of the purest free base ephedrine I’ve ever seen. Even though the compared theoretical yields are less with method #1, it’s worth it in my opinion. Only thing to do after that is turn it to it’s HCl salt.

 

[Nacho]

Wash with non-chlorinated brake parts cleaner. You will lose no psuedo and it will take away most of the filler and binders as well.

 

[Lordoftheshard]

As long as you external steam distill the reaction mix you will be ok and and your lye dry no water untill you steam distill 2,to 1, ratio Of lye to pse Nd don't worry about lye lock the steam will break it all down