Could obtaining the stability @ 125F/ higher temps and then lowering the temp to around 87F for terpene retention be a good idea?
with ethanol shatter, most of your terpenes will be gone if you purge at 125. This isnāt necessarily a bad thing, imo with shatter you only want a hint of flavor. A continuous vacuum for the initial ethanol purge when it is muffining up a lot, once it calms down you can close the vac and it will do just as well.
I feel a continuous vac would dry it out further.
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Came in this morning to flip my slabs and found one of them like thisā¦
100Ā°f @ full vac for 12hrs
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Was this older material? how does it smell ? terpy?
Cured material - about 2 months old
The terps remaining are subtle in aroma but there for sureā¦
Going to melt her down and try to recrystallize
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If its getting sugary like that, then there are most likely too much terpenes in it to make a stable shatter. More terpenes means more for the vacuum to pull on, and more possible nucleation sites. Temperature will affect how much pull the terpenes feel from the vacuum, but if you are also still trying to purge ethanol, you will have a hard time purging the ethanol with out pulling the terps as well.
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How are you going to recrystallize?
Good luck
it was actually very stable
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pentane
i meant more stable in the sense that it will stay as shatter, as opposed to structural hardness (not bending)
Vacuum plus heat are the standard way to do it; I was just suggesting that adding stirring is a great way to further reduce impurities.
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Ive always wondered, is the boiling point of the solvent your trying to purge from the extract the only factor to consider?
Do the intermolecular forces between the solvent and the solute play a role in purge time as well?
To illustrate my question a little better, if you had two separate grams of distillate and dissolved each in two solvents that boil at the same temperature but have differing polarity would the intermolecular forces between the distillate and the solvent play a significant role in how quickly the solvent is removed from the distillate?
What do you guys think?
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Polymerization on the top layer of your slab can trap solvent regardless of boiling point (purging honeycomb), to fight this we flip slabs.
I have found spreading the oil in a super thin layer works but its a bit of a pain and it clogs up the oven space.
In my research I have noticed that vacuum hysteresis (up and down within a range) helps to fight slab surface polymerization and greatly reduces purge times on higher boiling point solvent extracts such as EHO,LHO, ISO etc etc
2Ā¢
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Vapor pressure plays a role, of course. Another aspect is how trace amounts of solvent become trapped in viscous or solid material. So yes, but you are already probably taking steps
Look at thc itself. Itās boiling point is similar to terpenes, but they have a much higher vapor pressure.
Another example, ethanol and some terpenes have a similar vapor pressure, making them form azeotropes. Some terpenes, like Limonene I learned today, donāt form azeotropes with ethanol, but is still volatile enough to form an azeotropes with water. Itās boiling point is vaguely similar to CBD, sort of, but see how district itās properties are?
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How does vapour pressure relate to vacuum? Are we still dealing with vapour pressure under vacuum? Iām just not clear on the concept.
A substance is boiling when the vapor pressure it exerts is equal to the pressure itās environment exerts. Under vacuum you are lowering pressure of the environment on the substance making the amount of pressure it needs to exert to boil less, lowering the amount of heat that you need thus.
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How is there a difference between what the boiling point is and the vapour pressure? Isnāt the boiling point a function of vapour pressured?
Boiling point is the temperature at atmospheric pressure required to make the vapor pressure of the compound equal the atmosphere.
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Iām just trying to unpack what that meansā¦ Sorry I donāt have a formal science background 
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