Propane VS N-Butane extraction

@Photon_noir or @Beaker may be able to give us a more accurate answer. I feel your are right, as well, but they do seperate. I’ve used propane mixes a bunch when I thought playing with blends was a good idea (I’m not saying it’s not, just a pain because the ratios are always changing) and they don’t stay together as one. This is why we use butane with propane or other similar solvents with low boiling points, to maintain a pour.

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I run strait propane quite often personally its my favorite for making diamonds in jars cause it creates more pressure u have to check the jar lids more often and extchange them but my biggest dry run crystals came from 100% propane and it recovers fast as fuck shatter just doesnt work ways sugars maybe winterizing it after with eto or pentane in cryo freezer would help for shatter

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@Krative might have some answers as well if he can find the time to chime in. My research has come up empty so far.

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It sugars bc ur to pure especially w extra terps, propane moves its balls cold

U need lil fats, propane may make it really hard for that reason alone

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Man my collection pot leaning this way…

That last amount always so slow! Makes sense

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I think dred pirate is speaking from experience in saying they do not form much of an azeotrope and they evaporate as seperate fractions. Azeotrope is a word thrown around alot in the space and is generally not used accurately. I think it would be useful for people to check out Raoult’s Law. Raoult's law - Wikipedia

I can try to field questions once people become familiar with this thermodynamic estimation of boiling point as it pertains to chemical mixtures.

So in short @StoneD I am not sure if a certain percentage of each butane or propane would form an azeotrope. I think a motivated person could figure it out with raoults law but generally I do not think many people have this trouble of azeotropes with the typical 80:20 and 70:30 mixtures

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I am under the impression that they are azeotropic at all ratios. The only way to confirm this is to recover 80-90% of a solvent blend repeatedly and get it tested, which I have not done.

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Please read the raoult’s law page. by defining something as an azeotropic mixture is to say the mixture of the two have the same boiling point when they are mixed. This interesting effect is only seen in specific ratios. This is the main way people confuse how they use the word azeotrope. Does that make sense?

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Yes, I appreciate the explanation but I am quite familiar with the term. Again, we need to just recover repeatedly and test the solvent blend at that point.

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I don t think they are azeotropic for the reason that mixed tanks or pure propane tanks have the same vapor pressure on the gauge
If azeotropic they would have a diffrent Reading
A diffrance of 40C In bp is seldom seen in azeotropes
What is seen is that say When boiling of hexane with water present a minor amount of water also ends in the receiving flask
Just because iT vaporizes at all temps

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Unfortunately this quote does not seem as if you understand the concept. Azeotropes occur at very specific ratios…

this may help you

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I can almost bet if you had 20f fluid flowing through a collection that was 50/50 propane and butane. Just the propane would boil off, leaving quite literally all of the butane there, as it’s below its own boiling point. When mixed, they don’t become a new solvent.

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When you look at how they seperate natural gas from the hydrocarboms it basically provides the answer, propane is recovered at the highest rate vs butane (90%) butane(75%), then pentane, then other heavier hydrocarbons (85-90%)

http://naturalgas.org/naturalgas/processing-ng/

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I find it interesting that hexane and water are immiscible in each other BUT when boiled together as a mixture will form an azeotrope and cannot be separated by distillation. I had hoped to recover pure hexane from my LLE which used only water by distillation but I cannot because of this. Aseotropes are an odd creature and much of what is known to me seems more of an art form than a calculated function. They are hard to understand because they play be different rules seemingly according to which two solvents are used. Take isopropyl alcohol and water for instance.

The two form an azeotrope until the water becomes saturated with salt. Then the azeotrope is broken and in fact the two can then be separated by fractional distillation. I think too it becomes ambiguous as to what an azeotrope is exactly when pressures down at one micron are at play. I have a hard time envisionining ptecisely what constitutes a boil in a condition under which there is no system pressure as a practical matter. I mean, if boiling temp depends on system pressure but there is no system pressure as a practical matter then what precisely is the boiling pressure at say one micron versus one half micron?

In my bedroom back woods tye-dyed lab it is seen that pressures below about 20 microns start to behave differently than a flask boiling above that pressure. This speaks to my amatuer status but it sure seems then like the spin bar speed can even play a role in “boiling point” only because collection of disty changes according to stir bar speed seemingly when thevstirvcar changes but the temp stays the same.

I am going to take a puff now and ponder… :sunglasses: @cyclopath might know. He knows everything… Hey @cyclopath!

PS… I am breaking tradition and puffing kief today! Venturing out into the green world lol but sometimes I just gotta hit some kief. It is not that good to me after all the resin I used but it is a nice liesurely afternoon. Not so brain numbing.

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Aside from tagging you, I was thinking about you this morning. I hope treatment is going well and you in good health.

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Thanks. It really does mean a lot. My chemo is doing well and seems to be holding the cancer at bay. Unfortunately by the time the tumor had escaped the liver it is now free to spread. Truth is that my treatment now falls into the quality of life treatment mode and no quantity of life. The drugs will extrend and make comfortable but there is not a cure when it gets like this.

I am honestly ok with this. It is just part of the deal we get when born and as for me I am using my time to enjoy myself. Fewer labs because I have other things to bang out but I still want to find a practical way to remove green by LLE. Physically there are days the pain is high and so I use morphine which works. I figure I have had a nice long life and now want to focus on playing with the dog and walking by the river. I unfortunately had to put down my sick grayhound, the female, from liver failure and that bumbed me out but life is life I guess.

Thanks for the inquiry. It helps to know people think of me. :sunglasses: It speaks highly of you.

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Thank you for tagging me, @Dred_pirate! You inspired me to write another treatise on extraction chemistry, here:

Extraction & van der Waals Force

At least I kept the TLDR out of your thread, @Merakian_Hash, right? :grin:

I hope you’re doing well, @Beaker! Call me some time!

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I’m glad you have a positive outlook. It does sadden me to know that one day we will have our last exchange. I will make it a mission to visit you and adsorb some of your knowledge to pass on to another generation.

Until then, enjoy good hash. And I hope to bring you some hash as well.

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So if I read that right and from what picked up from everyone, pressure can change the condition

We are not recovering at zero psi…more like 5-20max(in the collection), will this change it. I still believe they go differently but I’m interested does this matter. Scientific stand point

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I’m absolutely loving the italics

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