Does anyone know if there are any significant differences in the effects on the purity of spice from doing a sodium carbonate wash versus a recrystallization? They both remove impurities. Is it redundant to do both or is only one or the other needed? Thanks.

both are just methods of cleaning up the product. Re-crystallization is superior, in chemistry it is the simplest and most effective way to obtain a highly pure product. Washing is more of a standard work up that you do in preparation for a re-x. In this case, to remove traces of basified bark or other aqueous impurities. The less crap going into the re-x, the better.

That makes sense. Thanks! My main concern is getting rid of the lye/bark solution out of the solvent. Re-x is good at doing this too?

So let me ask you this. What would be better, one sc wash followed by a re-x or two re-x with no sc wash? I also see a lot of people over looking a slow tempurature change for re-x, e.g., cooling at room temp, then in refrigerator, then in freezer. Is this overrated and unnecessary or does it really produce much cleaner crystals?

Thanks again for the info!

about the same, but 2 re-x is overkill and a time waster. do the lazy way, sc wash and then re-x, more than enough. slow temp is better, not overrated. the slower the crystals grow the more pure they are

Tried a re-x using slow temperature change and got some really nice 3-D crystals.