Do you really need to re-proof (5% heptane denatured) ethanol?

Hash and Stuff Extraction
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Seems the consensus is yes, but my experience says it’s not really necessary. I’ve only ever extracted with heptane denatured ethanol. Hydrometers are useless it seems for checking proof of this solvent, so I really have no idea how much water is in my solvent. I’m familiar with the ternary azeotrope that ethanol, water, and heptane form and have considered removing water using this principle.

But is it even necessary? I have done this experiment several times now, extracting the same biomass with fresh, brand new solvent and with solvent that has been heavily recycled and extracted 100+lb of thc biomass. Always the same result. Identical yield, color, potency, etc. I expected that I’d see improved yield, better color, etc. with brand new solvent. No issues with extracting sugars (that I can tell) with recycled solvent.

I’ve talked to several people that say they get quickly diminishing returns using the same solvent system. Am I just very lucky lol? Thoughts? Anyone else not reproof heptane denatured ethanol? Do you re proof this solvent system? How often do you reproof? After how many lb’s extracted? Is it the just a case that I’m not noticing the diminishing returns because I’m not extracting enough biomass for it to manifest?

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How are you further processing your primary extract? Might play a role in why you’re getting away with not re-proofing your Ethanol.

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Can chime in here. Have done this same experiment several times. No difference in crude quality and no differences down stream.

I’m sure there is a level at which it is not longer as effective but never reached it due to Losses from extracting

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I’ve used the same 50 gallons (food grade ethanol) at least 4x over. I always check proof out of the rotovap. It’s always +195 as indicated on my proof gauge.

This is always with di directly in biomass and ethanol. 3.5ph ethanol

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Interesting. I have had really bad experiences when recycling solvent. I get super green solution/extract. Maybe I need to try it again, as i have a few drums of reclaimed solvent…

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Super green = chylorphyl
Means your not washing biomass cold enough. But green (chylorphyl) shouldnt come over in a rotovap.

Pass green etoh over a cake of ac. Color removed.

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The facility I am with now reused ethanol for close to a year. Due to it’s hygroscopic nature and subpar enviromental conditions we experienced issues in decarb. After buying new ethanol it solved our problem. Just my .02 cents

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No other processing generally. Extract cold (-80 to -60C), filter sediment (no AC or clays), rotovap, decarb, distill. Crude and distillate do not seem to differ in any way regardless if I use new solvent or heavily recycled.

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Depends on the water content of your biomass and the extraction temp.

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So I don’t know the water content with any accuracy, but it’s dried trim mostly. When I do get test results ~5% moisture content is common. Extraction temp is -80 to -60C at the warmest (I extract in a -80C chest freezer).

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What kind of issues did you experience with decarbing?

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I can’t speak for him or her, but it sounds like a critical concentration of water was reached, which cockblocked efficient heating of the mixture during the decarboxylation step in their process, or possibly was not purged well and made the downstream processing unhappy

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When water is added the ethanol becomes less aggressive so your yield may drop but the ethanol will also pickup less chlorophyll and other high molecular weight compounds.

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IME you usually lose it before it becomes a real problem, id say (based on ur extracting parameters) its probably close to 10x uses before u start extracting 10% less per same volume of alcohol (just add 10% more). Then probably 20 uses, 20%, etc etc.

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