Tobacco extraction using heated Ethanol

[kbriggs]

Did you notice any reaction when you rinsed the 150g of sieves in water after they were exposed to the PGA the other day?

No, it felt room temperature to me.

 

[Str8vision]

Was reading about the "proper" method of activating/re-activating sieves and ran across this: "To verify that the sieves are active add water to a small sample. If they get very hot, you’re good!"

 

[Str8vision]

Also read that sieves will absorb water even at 120 degC (250F), activating them requires several hours of time at 250 degC (480F).

, a little late but;

Cautions.

• Air dry the molecular sieve from empty solvent bottles in a fume hood draft until they appear dry before heating at elevated temperatures. While the sieves bind much water, they also hold some solvent and you don't want to heat the pellets very hot with a lot of solvent present. (Fire hazard.)

Rinsing isn't adequate because some solvent (ethanol in our particular case) is held in the sieves, not just on them. This would certainly explain your "flash". This also will increase the amount of ethanol lost to the sieves during each pass. I had counted on some loss due to surface adhesion but looks like it'll be a tad bit more than just that.

 

[kbriggs]

Was reading about the "proper" method of activating/re-activating sieves and ran across this: "To verify that the sieves are active add water to a small sample. If they get very hot, you’re good!"

Interesting, so that should happen every time? Did it explain why?

 

[kbriggs]

Also read that sieves will absorb water even at 120 degC (250F), activating them requires several hours of time at 250 degC (480F).

I've been drying my distilled-rinsed batch this afternoon at 400 F. The pre-washed weight was 365.4 g. After 1 hour of drying it was at 384.0. After 2 hours 373.3 g. After 3 hours 371.2 g. So I just now raised the temp to 500 F and will give it another hour to see if I can get it down to the original weight.

 

[kbriggs]

I've been drying my distilled-rinsed batch this afternoon at 400 F. The pre-washed weight was 365.4 g. After 1 hour of drying it was at 384.0. After 2 hours 373.3 g. After 3 hours 371.2 g. So I just now raised the temp to 500 F and will give it another hour to see if I can get it down to the original weight.

So that last hour at 500 F did the trick. Got it down to 364.5 g, slightly lower than the factory weight. The dust removal might account for the slight difference. Anyway 400 F is not enough, need that 480+ F recommended temperature. I'm going to re-dry my original 150 g batch and then use it again on my PGA to squeeze out that last 3% of water.

 

[Str8vision]

Interesting, so that should happen every time? Did it explain why?

Every time. No explanation, just reassurance/confirmation indicating heat is normal if activated sieves are dropped in water.

 

[kbriggs]

Every time. No explanation, just reassurance/confirmation indicating heat is normal if activated sieves are dropped in water.

It must be the actual water absorption and not just the surface contact. Which would explain why I didn't detect any heat putting them in the PGA.

 

[Str8vision]

Concerning why sieves get hot when exposed to high concentrations of water; "The heat is caused by the formation of adducts between the sieve and water. Weak (most of the time) bonds are formed between the drying material and the water, this is how the water is held, making it possible to remove water (nearly) completely."

So it's exothermic: rapid bond formation. Formation of numerous hydrogen bonds yields a lot of energy (heat). Only happens if the sieves are in an active state and exposed to high concentrations of water, even small amounts of it. It's not dangerous or harmful. I've read that you can use this phenomenon to check if a batch of sieves are active. "Place a few sieves in the palm of your hand and add a single drop of water to them, if they get warm they're active. If the sieves are really dry the heat will almost be painful but only for a second."

 

[kbriggs]

Formation of numerous hydrogen bonds yields a lot of energy (heat).

I wonder if these could be used in some kind of camping/survival scenario to heat food or just keep yourself warm in an emergency.

 

[Str8vision]

I'm not sure the reaction between activated molecular sieves and water would last long enough or get hot enough to be very useful in such scenarios. For a better solution Google "exothermic chemical heater". The military uses them to heat MREs in the field. The primary ingredients have many other useful purposes in a camping/survival situation. However, just like molecular sieves, the primary ingredients must be kept/stored moisture free or they wont work when needed. Mylar bags are ideal.

 

[leftyandsparky]

Update.... still waiting to try it. Hoping to give it a little age to it.

 

[Str8vision]

Update.... still waiting to try it. Hoping to give it a little age to it.

Did you catch much gunk with freeze filtering? Have you mixed the the finished extract into NET?

 

[leftyandsparky]

I pulled a lot of yucky stuff from the first 2 coffee filters and left the gunk in the bottom of the jar. The final special filter left a very clean looking extraction. After reduction, I mix 10% of the extraction with nic and vg.

 

[Str8vision]

You might consider allowing the mixed NET to sit open-air for a day or two to drive off some of the ethanol. I use a rubber band to secure a coffee filter over the mouth of a canning jar for doing this, it protects the NET from airborne contaminants (like dust).

 

[leftyandsparky]

I did! I actually opened it every morning for 3 days for a few hours.

 

[Str8vision]

I ordered the 3A molecular sieves yesterday, got a pound of the 8-12 mesh size beads. I still don't know if removing the 5% water from my ethanol will benefit flavor but since there's no real downside to doing so I'll convert a 1.75 liter bottle to start with. Luckily, I have a gallon size glass jar which should work nicely. Once finished I'll decant the pure ethanol back into its original glass bottle along with some activated sieves to help keep it moisture free.

Also lucked into finding 5.5cm diameter 1 micron Borosilicate glass microfiber filters on sale, $18 for a pkg of 100. They're normally $100 to $120, I got the very last last pack available at the reduced price. I noticed they also have a hundred of the 12.5cm size available for $39 (they normally cost around $200), a bargain but I don't need the larger sized filters since I have/use a filter holder. 5.5cm fits my "Busy Liz" canning funnel perfectly. I still have over two hundred left from the last time they were on sale (2015 ?), but this was by far the cheapest I've ever seen them so thought I'd take advantage.

I didn't really need it but I liked the looks of the Digiten pre-wired temperature controller so much I ordered one. If it works as good as my old PID controller I'll let everyone know.

 

[leftyandsparky]

Tried my extraction and I think it still needs a little age to it.
It had a grassy note to it.
How long have y’all aged extraction before enjoying them?

 

[Str8vision]

Tried my extraction and I think it still needs a little age to it.
It had a grassy note to it.
How long have y’all aged extraction before enjoying them?

That grassy/hay/straw note comes from the generous amount of Virginia tobacco that's in Louisiana Red (and most other VaPer tobaccos) but aging should mellow it out. How long the mixed NET needs to age depends on the taste preference of the person using it. Here were my thoughts back in 2014;

.....I fully agree that aging often improves the flavor extracted from tobacco, in some instances I've noticed the improvement is nothing short of stellar. Two of my favorites (Voodoo Queen and Louisiana Red), tasted rather anemic right after extraction and required "months" of aging/steeping before reaching their prime........

 

[leftyandsparky]

I will try it again in a month......