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Re-ex and water wash advise

CokFLHX

Esteemed member
Hello all.

I had about 10g of product that I dissolved in hot heptane, and is now precipitating in the freezer.

I’m concerned, because I did all of it at once. The nice pretty white crystals and the crusty stuff stuck on the blade. The resulting saturated solvent looked to be stained and I anticipate the crystals from this reex will be yellow or orange.

No big deal, right? Fine as is, or you can clean it up with a water wash, I think…. Ha.

My plan to water wash is to have three small glasses, filled with hot RO water, with the first containing a pinch of sodium carbonate. I plan to redissolve after scraping thr reex into hot solvent, and mixing waiting tomseperste, and mixing into each glass of water before the final destination will be the glass dish and the freezer.

Here is my concern.

The last time I did a water wash something got messed up. I tossed the water when finished and lost almost half of my yield.

I plan to keep the water this time just in case. If I have the same issue I’ll see if I can’t salvage it from the use wash water but I wanted to ask if what I just laid out sounds right? All the teks ive read seem to list that is the procedure.

I just hate to waste a lot of time and effort with a stupid mistake. I get nervous doing a reex to be honest. But I like those white pure crystals.

Any advice is most welcome. Thanks for your time.
 
Hello all.

I had about 10g of product that I dissolved in hot heptane, and is now precipitating in the freezer.

I’m concerned, because I did all of it at once. The nice pretty white crystals and the crusty stuff stuck on the blade. The resulting saturated solvent looked to be stained and I anticipate the crystals from this reex will be yellow or orange.

No big deal, right? Fine as is, or you can clean it up with a water wash, I think…. Ha.

My plan to water wash is to have three small glasses, filled with hot RO water, with the first containing a pinch of sodium carbonate. I plan to redissolve after scraping thr reex into hot solvent, and mixing waiting tomseperste, and mixing into each glass of water before the final destination will be the glass dish and the freezer.

Here is my concern.

The last time I did a water wash something got messed up. I tossed the water when finished and lost almost half of my yield.

I plan to keep the water this time just in case. If I have the same issue I’ll see if I can’t salvage it from the use wash water but I wanted to ask if what I just laid out sounds right? All the teks ive read seem to list that is the procedure.

I just hate to waste a lot of time and effort with a stupid mistake. I get nervous doing a reex to be honest. But I like those white pure crystals.

Any advice is most welcome. Thanks for your time.
I never loose any crystals and just put them in a coffee filter and wash with cold water. I would soak it like a tea bag as much as possible as you see oily solvents rinsed away.
 
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