Definition of multiple "pulls" vs freeze precipitation process?

[Gojoe]

Everything else has seemed pretty straight forward in following marsofold's tek, the only question I have after countless hours of searching is about multiple pulls.

For example if I were extracting from 1lb of mhrb the updated portion of the Tek calls for a 500ml pull with evap down to 10% prior to freezing. A lot of reading has led me to believe smaller increments of that 500 pull will lead to a better yeild.

So my question is, if I break up the 500 ml pulls, do I still put the full 500mls in the same Mason jar for freezing? Separate jars? If you wait 3 hours between pulls as the Tek recommends, won't some initial solution evaporate before the second and third pulls?

And once the 500mls is pulled and multiple extractions are done from it, is the base solution now waste product? Or can more NaOH be added for more pulls?

Thanks and I apologize if these simple question's been answered. I've looked everywhere.

 

[Incarnation]

500mL seems like a lot.
But it sounds like the tek would still have you evaporate the combined pulls down to 10% (50mL) before placing in the freezer.
A flat glass dish might be easier to scrape later than a mason jar.

 

[pete666]

Have you read FAQ?

 

[blue.magic]

So my question is, if I break up the 500 ml pulls, do I still put the full 500mls in the same Mason jar for freezing? Separate jars? If you wait 3 hours between pulls as the Tek recommends, won't some initial solution evaporate before the second and third pulls?

500 ml seems way too much even for that amount you mentioned. You can do more smaller pulls.

No it won't evaporate as long as you keep it in closed container - naphtha or heptane don't evaporate that quickly even if left on air at room temp.

I would not go for 1 lb of bark for starters. Extract something like 50 g first and learn how that works, then scale up slowly.

However, note that we don't discuss large scale operations here.

And once the 500mls is pulled and multiple extractions are done from it, is the base solution now waste product? Or can more NaOH be added for more pulls?

Yes and no.

There is a certain amount of alkaloids in the plant. Adding enough base will convert say 99.95% of them to a free base soluble in the extraction solvent. The first pull will remove say 75% of them, second pull 15%, third pull 3% and so on.

Adding more base and doing more pulls will give little bit more alkaloids, but the returns are quickly diminishing to amounts next to nothing. It's basically scraping the last specks from the bottom of the plate.

Three pulls are usually enough to get most of the alkaloids. Further pulls does no usually worth it.

Depending on the amount of solvent and solution, you may need more pulls, but that depends on several factors - look up A/B extraction or liquid-liquid extraction in any chemistry articles to learn how that works.