EtOH suppliers - rep / verified?

CDA12 does not seem like a drop in replacement for 190 unless it can be returned trivially to its starting point.

We are agree that distilling whatever proof ethanol/water mix I have will get me back to my starting point?

190proof. Which is where I want to be. Easy peasy, go to the azeotrope and you’re done. Almost impossible to get wrong.

My question is how do I return to my starting point when using CDA12?

It seems like considerably more work, and it’s not clear how I determine the end point even after I’ve figured out how to get there.

Adding more stuff (pentane?) to make that happen is certainly a formal solution, but I’ve got minions to train and each additional step leaves another opening for production errors

Let start with: How I can confirm that I’ve returned to 200proof ethanol w/5% heptane?

Or maybe even, how much heptane is in your CDA12? I’ve heard up to 15% on occasion…I guess I could throw a sim-dist column in my GC…but again, not a problem I’ve run into with ethanol at azeotrope.

Hexane forms an azeotropes with ethanol and acetone.

Heptane forms an azeotropes with water and methanol.

They both form other azeotropes with stuff less likely to be in your lab.

Clearly what I deserve for my efforts to dissuade spoon feeding…:roll_eyes:

Still looking for a way to understand my recovered CDA12

:spoon:
:pray:

Can’t throw cash, will share stash :slight_smile:

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Ok, so, I’m not the biggest fan of ethanol. I have never used the blends above, so I first wanted to see what denaturant formulas are allowed in the USA.

The FDA didn’t help; these seemed the closest (per 100 gallons):

  • 5 gallons of methyl alcohol.
  • 10 gallons of ethyl ether.
    *. 100 gallons of ethyl ether.
  • 8 gallons of acetone, U.S.P.
  • 8 gallons of acetone, U.S.P., and 1.5 gallon of methyl isobutyl ketone.|
  • 10 gallons of methyl alcohol.|
  • 5 gallons of ethyl ether.|
  • 25 gallons of ethyl acetate having an ester content of 100% by weight or the equivalent thereof not to exceed 5 gallons of ethyl acetate with an ester content of not less than 85% by weight.|
  • 3 gallons of ammonia, aqueous, 27 to 30% by weight; 3 gallons of strong ammonium solution, N.F.; 17.5 pounds of caustic soda, liquid grade, containing 50% by weight sodium hydroxide; or 12 pounds of caustic soda, containing 73% by weight sodium hydroxide.|

Sorry for the copypasta…

So when I google CDA-12 I find a little more.

CDA 12-A §21.26 Formula No. 12-A
(a) Formula. To every 100 gallons of alcohol add: Five gallons of n-heptane, or 5 gallons of toluene.

CDA-19 § 21.33 Formula No. 19
To every 100 gallons of ethyl alcohol of not less than 160 proof add: 4.0 gallons of either methyl isobutyl ketone, mixed isomers of nitro propane, or methyln- butyl ketone; and1.0 gallon of either kerosene, deodorized kerosene, gasoline, unleaded gasoline, rubber hydrocarbon solvent, or heptane.

CDA-20 § 21.24 Formula No. 20
(a) Formula. To every 100 gallons of ethyl alcohol of not less than 195 proof add: A total of 2.0 gallons of either unleaded gasoline, rubber hydrocarbon solvent, kerosene, or deodorized kerosene; or any combination of these.

So CDA-12 is either 5% n-heptane or 5% toluene.

Heptane does not form an azeotrope with ethanol, but does with water. It boils at 92C, so it would always be the tails of you distilled CDA-12 containing it. Should your CDA-12 contain toluene it would be harder to remove. Since it gets complete with a water-ethanol azeotropes and a water-heptane or water-toluene azeotrope I’d be careful if I wanted to use it many times, and hope I got heptane and could distill it to purity, if it was the only option.

Better sourcing may be in order … some of the FDA approved blends seem less headachey, but it’s possible I’m ignorant and that product is optimized for this process off label.

Edit:

Acetone or methanol look cleaner to me as denaturants bc the only azeotrope would be alcohol-water.

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We sell whatever you need with 20kg media or 55 gallon liquid minimums.

CDA 12 — are you adding water to have a 190 proof starting material or just absorbing water from biomass??

190 proof seems to be best.
I don’t know what your sop or equipment or methods are…

Extract, reclaim then use molecular sieves to absorb h20.
Test solution.
Run solution through rotovap / reclaim again
Test solution

That should give you enough info to move forward.
Do bench top scale and scale up from results

Have you had any samples tested to know what condition your solvent is at after several runs?

and THAT is my point…

I can test my ethanol. & know where I am. How do I achieve that with CDA12?

And CDA12 can contain toluene instead? No thanks.

Why would I use a solvent that I need to check in with a chemist to see if it’s still on point.

Because it’s cheaper?
But I get almost all of it back!

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Ok so you are asking, “how do I find out how much heptane is in my solevent? How much water?”
You are assuming you always have 95% EtOH when using that alone and distilling.
Correct? And that is all?

1st: Thank you! I’m not a chemist, and will never claim to be.

I don’t simply assume 190 when I distill, I measure density at known temp using what the moonshiners would call a spirit gauge.

I certainly have to agree that after multiple passes over biomass there will be more than just ethanol in there, and I have been assuming those effects were negligible.

I have absolutely seen that my “tails”, pulled out in a rotovap rather than my still, are often not at 190.

I don’t combine those back, and use them for cleaning surfaces or spills. I should probably toss more of my heads than I do…

When doing Bucket Tek (Cold Ethanol Extraction on a Budget), one loses a lot of solvent, so co-distilled terpenes in the recovered solvent is compensated for by constant addition of fresh solvent.

Once one adds a centrifuge to regain more of the solvent (I’ve seen claims of 98% removal), it has been noted that the 190EtOH can acquire off odors. The simple fix there would seem to be to use vodka (activated charcoal) filters. use them every time. == same solvent every time.

I’m watching a facility spin up using the heptane denatured, and it baffles me.

There is a remote chance its the biomass.

Tried 190. worked great.
Tried fresh CDA12, worked great.
caveat: it was on different biomass.

my working hypothesis is that they picked up water from the biomass. probably early on when they hadn’t figured out how to get their solvent cold enough. by the time they had their temps under control they had water in all of their solvent. but my assumption is that there will always be some water pickup.

it seems to separate when chilled. (once water gets involved? )
which presumably makes drawing from tanks problematic.

If it’s just water removal, then yes, I’m an idiot and I can throw molecular sieves at the problem, but I’m concerned I’m not the only idiot out there, and it’s being pushed as a drop in replacement for 190 ethanol…without examining (advertising?) the process tweaks required.

I’m also not certain that water removal is all there is to it, it was stated above that heptane and ethanol do not form an azeotrope, these guys beg to differ
https://pubs.acs.org/doi/10.1021/ie8011769

this suggests the layering I’m seeing maybe the water/heptane azeotrope

or as said by someone not being sold the formulation as a drop in replacement

Lewis_Bronsted:

Better sourcing may be in order … some of the FDA approved blends seem less headachey, but it’s possible I’m ignorant and that product is optimized for this process off label.

it might be…but that is not my first response upon using it…seeing it used really, I’m just getting their BOCK installed…

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S.D.A.-23A seems like a denatured formulation to consider. The denaturant in question should decrease fat solubility at cold temperatures, and it’s not toxic at all. I can’t say that 5% v/v is ideal, but combining ethanol and that simple ketone can likely be superior. Acetone doesn’t form an azeotropes with ethanol.

Thanks for catching that I missed the heptane ethanol azeotrope. I’d have avoided using it and finding out if I could lol it’s getting complex, and acetone/methanol aren’t too bad :wink: by which I mean as denaturants for ethanol.

Ethanol-heptane
Ethanol-water
Water-heptane
Water-lots of terpenes one by one
Ethanol-different terpenes

Is that all? Lol

190 is simple, and can be dried with sieves if needed, so it’s all what’s facile

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I expect most won’t be using membranes for a hair longer than that :wink:

…and the extracted CBD crude tasted sweet. Presumably residual heptane…

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Ya that would be scary :grimacing:
Decarb it then taste
It’s all guessing until you get it tested

But that’s probably why most people don’t test on themselves first

“Here blaze up this wax that smells like sulfur”
Never know — could be how we got “hairless female primates”…that was great
That actually makes me slightly concerned about the unregulated hemp and cbd market
Probably lots of pesticide and shiT out there that isn’t going to be regulated to test.
Looks like FDA oversight is probably gonna be a great thing in the end.
Just wish we had more university studies but that time is here

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@Lewis_Bronsted and @anon86230761 here are the wizards words on the subject I mentioned earlier.

I can make more sense of them now they have been written :wink:

Especially having done the suggested reading first.

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Hell to the fuckin YES, @Lewis_Bronsted! S.D.A.-23A, eh? Gotta look that one up! Thank you!

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Well end of story is stick with etoh.
I was looking to beat the energy requirements of refrigeration — not gonna happen until membrane tech.
Stick to safety I guess :rofl::man_shrugging::man_pilot:

I do think liquid nitrogen freezing tunnels however would Be a brilliant addition to the arsenal vs cryo freezing the bio for extraction

Looks like you need a fed alcohol tax stamp for that as it’s “specially denatured” if you have that licensing might as well get cheap 190

I don’t know anything about the tax stamp but it seems specially denatured alcohols do cost more - pretty close to that of ethanol as you say, and that the completely denatured alcohols all have troublesome azeotropes. Distilling off the azeotropes first before use would be advised - but is that even legal? For the record ethanol laws are not my specialty… the SDAs are used for food and drug applications, so they are definitely indicated, however so is food grade ethanol, lol.

I’m going to look at this more, it’s fascinating, and I’ll share my findings if there are any.

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ATF mafia. As far as I know, it’s all about potable or not. Apparently, you can get a tax credit or variance or whatever you wanna call that…exemption if you can prove or provide it is not being used for drinking.
Now that hemp is legal, game is changed.

I also will post something if I find that answer and how to file and the steps etc

That would be very useful to all and likely much safer with more pure ethanol use especially for the people that don’t get tested

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From SA:

“To purchase Specially Denatured Alcohol, customers must possess an Industrial Alcohol User Permit from the Alcohol and Tobacco Tax and Trade Bureau (TTB).
• Permit must have customer signature and date of submission to Sigma-Aldrich in addition to the original signature and date.
• Permit must have word, “copy” handwritten or stamped.
• Permit number must contain correct state or US designation matching ship-to address.
• Permit address must match ship-to-address in Sigma-Aldrich system.
• Permit only needs to be provided on first order to sigma-xxx@sial.com.
• All orders require that a PO with the statement, “valid permit #####” be submitted to sigma-xxx@sial.com.”

I have a friend who has to have this permit to grow hemp etc in his local jurisdiction, I still am not super clear on it all.

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