do you have a filter-dryer on your setup?
I do not. Where would it go in the set up? And what would the function be?
I think he is referring to a vessel with 3/4/10 angstrom mol sieve for drying the gas etc. It would go after solvent evaporation.
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It seems like the issue is going to be the temp being too cold. We are going to try few different temps tomorrow between -30 to -60. Im guessing this only applies to dry material(cured, sugar, smalls, nugs)
Because we used to run co2 on original bizzybee system few years ago and never encountered this problem with fresh frozen. And co2 kept the systen temp between -60 to -80
THCa is THCa and 'tane is 'tane, regardless of how fresh your flower is.
It could be outliers, like extraction technicians not being entirely honest (possibly they lost a bunch during collection??)
It could be pre-extracted biomass, maybe a sock or three got shuffled?
If youâre certain itâs not temps, begin exploring alternatives I guess?
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We never ran that low, nor did we get green concentrates with BHO, but my best wild ass guess is that you are too cold.
We used LN2 for a refrigerant and extracted at -30C minimum and nominally around -50C using the Mk-IVC & VC. We also pre-chilled the material to -10F/-23C.
What is your extractor design/setup?
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The higher the ratio of propane content in the blend, the warmer you need to extract if you want to extract. Solubility rulesâŚ
The smaller molecule (propane) has a harder time holding on to big molecules (THCa) at low temperatures than does a bigger molecule like butane at the same temperature.
Pure butane pretty much requires lower temps because it will pull more impurities than pure propane will at the same temperature.
For our systems we suggest a 70/30 propane heavy blend and has a pretty optimal extraction around -20c using a 10:1 ratio.
Also, if you are using a temp gun on stainless you will get an incorrect reading that is typically 15-20 deg above the liquid temperature in the jacket. Stainless is more of an insulator than a conductor of heat.
If you have an infrared imaging gun you can stand in front of your stainless supply tank and wave at it and see your reflection in the IR image. So basically on both the inside and the outside the stainless itself is reflecting the heat instead of transmitting the heat. Adding tape gets the number closer but itâs still not perfectly correct and will be off 5 to 10°.
As long as youâre below zero c during extraction water canât melt because it freezes at zero c so for live resin as long as youâre below zero c you should be good.
I actually once had somebody try to tell me that the water melted at -20c and formed an ice block in the bottom of a sock⌠Which in reality thatâs caused by an incomplete extraction and itâs a THCa block in the bottom of the sock. 
Solubility Parameters - Theory and Application by John Burke
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if you dont have a mol sieve/filter-dryer you could of crashed out all the water etc. in your solvent. I have never pulled chlorophyll like that with a super cold run, thats just my experience though.
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-80 is way to cold to extract. Your fucking yourself over. You should never really need to be below -40âŚ
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The higher the ratio of propane content in the blend, the warmer you need to extract if you want to extract. Solubility rulesâŚ
Nicely put! So i guess the race to get my system to run at -80 was over ambitious? Or not necessary at all? -40 could have done it all along! But what about the HTE, are all the fats and lipids removed at -40?
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I have a sieve column but i that comes into play after recovery, our issue was at the first step of the run
Yeah at -80c, especially with a higher propane ratio, youâre pretty much only going to extract terpenes, flavonoids, carotenoids, maybe some neutrals, and leave all your THCa behind along with the waxesâŚ
There is a little bit of a critical point with temperature and solvent selection for blend to minimize waxes in your extraction but the temperatures required to remove waxes happens to also be the temperatures required to remove THCA via cold crashingâŚ
Pure propane you can cold crash at around like -15 to -20c. Very little cold is needed for pure propane. Blends with butane obviously need to be a bit colder and thatâs where The typical -40c comes into play but it can get down to as far as a negative 60c depending on how hard the compressor pulls the vacuum down.
The 7030 propane heavy blend we suggest is pretty much perfect for our system design because you get all of the pressure benefits of a nearly pure propane blend as well as the liquid pour out of a butane run without the impurities that butane would drag along with it and without the slow speed of butane.
The high pressure of propane means high flow rates and high speed of extraction.
There is also of course the consideration: âis your system rated for propane useâ, which not every system is rated for propane operation and you should make sure that it is before you use it for that purpose.
I have found that anything near -20c is pretty much optimal it could be -10 -15 -30 -40c and all of those are pretty much adequate extraction temperatures except for when you get closer to -40c⌠Then youâre going to have a harder time extracting because you need a much larger ratio due to the low temperature.
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Thank you, this is lotta useful information. Now it makes sense we why only got terpenes from the extract we did a -80 and no thca. We are trying 90/10 butane/propane mix at -30 and -40, then stick to the temp that gives us higher yield. Or do you suggest i go back to 70/30 blend at -20.
Also, this system is rated for propane
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To decide to switch over to a 70-30 propane heavy blend you do have to acknowledge that you have to move more gas through your product to get all of it out but it will be always cleaner and will need less media.
Our systems are specifically set up for it but the traditional methods are not necessarily designed for that purpose. Itâs our patented cycling methods that make it more feasible than the traditional setup for the high propane blend.
It may be advantageous to stick with the higher butane blend if your systemâs volumetrics are not right for a higher propane blend.
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-40 on the chiller with 90/10 blend worked really good for us. HTE is little waxy but overall good place to start right now. We are going to play with the chiller temp until we find the sweet spot. Thank you for the help 
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thca will crash out of tane around-40. it will crash out of propane at -20.
so if youre running cold and want to maintain somewhat of a yield, gotta adjust a few variables. like soak time. the colder i run the longer it soaks. also, pressurized soaks (something about this makes all the difference in the world! a 10 min soak @-60 with a 5:1 solvent ratio and 100 psi for the soak. its like the pressure is pseudo equal to temp. and the pressure will convince the solvent that it can dissolve the target.)
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Depends on your ratios.
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Interesting comments. Variations of mangled and freeze fractured biomass.
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Excellent observations to note. Of course there is no known description of the state of cannabinoic acids in situ. @Roguelab had made notes on this forum, concerning Propane at temperatures less than -20 being a very poor solvent, and also comments on butane at temperatures less than -60. So the OPâs comments concerning his mixtures of butane propane at 70/30 are just additional data points on the solubility phenomena.
Have you investigated the âHeadsâ phenomenon under similar conditions. Heads suggest that terpenes are not necessarily acting as âsolventâfor the Cannabinoic Acids in situ, and can be selectively removed. This would fall into your concepts of variations of temp and pressure for optimization.
It would be interesting if someone would just run a small brick of purified âdiamond â material at these temperatures and pressures. It would give us a more detailed knowledge of cannabinoic acid solubility in alkane/alkane mixtures at low temp.
Just remember that the reported crystalline state is a dimer with each monomer having an intramolecular h-bonded ring. It should be pointed out that the state of cannabinoic acids in situ (trichome) storage volume, may well be a mixture of cannabinoic acid dimers and monomers crystalline dispersions/solutions in terpenes and or as cannbinoates exhibiting very strong intramolecular H-bonded forms that are also soluble in alkanes (at appropriate temp).
At some temperatures the terpene eutectic liquid state must âfreeze upâ trapping the cannabinoids. Such semi solid states demonstrate a selectivity towards butane vs propane, and further affords a selective extraction of terpenes at correct temperature as evidenced by âHeadsâ phenomena.
The rosin pressing of trichomes at much higher temperatures tells us that given the appropriate pressing temperature and pressure, the terpenes can dissolve the cannabinoic acids . However, if the pressing occurs repeatedly stepping from low to high temperatures and repeatedly pressing, the terpenes can be selectively removed leaving the cannabinoics behind as crystalline form.
*A eutectic system or eutectic mixture is a type of a homogeneous mixture that has a melting point lower than those of the constituents.
Note addedâŚSee @Zack_illuminated explanation of selective extraction (âheads phenomenaâ) above, critical temperatures and solvent choices.
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High pressure hydrocarbon extractionâŚ
Part of my first extraction patent for cycling of hydrocarbons allows increased extraction pressure, which in turn I found increases extraction efficiency many years ago.
We use HPHE for different materials, cryosift, kief, etc. works great to ensure complete extraction of the bio. Cancels out solvent channeling and more.
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