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Purging Bho methods

I would posit that the best way to possibly extract the butane is to blast on to a warm glass (~ 39 deg C) and quickly place in a vacuum, preventing the solid state from forming before all the gas can be trapped inside. Quickly cooling the extract probably allows more gas to be trapped, leaving a higher starting ppm concentration of butane. This is based on chemical theory though, not actual practice as I haven't made BHO in years...
 
*this post is referring to Maf's last post

sorry man i have nothing more to say on the subject as it stands. i have offered the most reliable sources i can think of, which is either to ask a credentialed chemist or consult any of the literature out there covering A/B extractions (e.g. a chem textbook). it's completely unreasonable to demand any further evidence from me when i'm already pointing to every possible source available and just expecting you to read it.

and where is the proof that certain molecules of butane will for some reason stop doing what they do naturally to deliberatly remain in the product?
 
I think there's very simple thermodynamic and chemical reasons for residual butane and other impurities, despite boiling points. Let's use the early genius of testing lead levels in the environment through ice cores... when a substance crystalizes (especially in kinetically favorable conditions, say... room temp THC/CBD oil) it crystallizes with gases still trapped inside the lattice. Increasing the temperature (heat) and decreasing the pressure (vacuum) allows the product to become viscous enough to allow the gas to become mobile within the semi-liquid state; the vacuum allows the partial pressure of the butane to be siphoned off, as well as as decreasing the boiling point. This is important because even the some of the lowest vaporization temperature gases (like nitrogen and oxygen) will maintain a consistent concentration in liquids due to the partial pressure at the surface of the liquid. One method (heat or vacuum) alone may not be enough, thus the low-heat vacuum machines. These are scientific facts, you cannot argue that a gas simply disappears from a solution because the temperature is much past it's boiling point (as every dissolved gas in water would tell you). Purging is a pretty responsible step to take unless you truly let the residue dry in the sun during the summer for ~ a week

this.
 
I think there's very simple thermodynamic and chemical reasons for residual butane and other impurities, despite boiling points. Let's use the early genius of testing lead levels in the environment through ice cores... when a substance crystalizes (especially in kinetically favorable conditions, say... room temp THC/CBD oil) it crystallizes with gases still trapped inside the lattice. Increasing the temperature (heat) and decreasing the pressure (vacuum) allows the product to become viscous enough to allow the gas to become mobile within the semi-liquid state; the vacuum allows the partial pressure of the butane to be siphoned off, as well as as decreasing the boiling point. This is important because even the some of the lowest vaporization temperature gases (like nitrogen and oxygen) will maintain a consistent concentration in liquids due to the partial pressure at the surface of the liquid. One method (heat or vacuum) alone may not be enough, thus the low-heat vacuum machines. These are scientific facts, you cannot argue that a gas simply disappears from a solution because the temperature is much past it's boiling point (as every dissolved gas in water would tell you). Purging is a pretty responsible step to take unless you truly let the residue dry in the sun during the summer for ~ a week

this.

*this post is referring to Maf's last post

sorry man i have nothing more to say on the subject as it stands. i have offered the most reliable sources i can think of, which is either to ask a credentialed chemist or consult any of the literature out there covering A/B extractions (e.g. a chem textbook). it's completely unreasonable to demand any further evidence from me when i'm already pointing to every possible source available and just expecting you to read it.

and where is the proof that certain molecules of butane will for some reason stop doing what they do naturally to deliberatly remain in the product?

To me it sounds like you are the one that doesn't really understand the basic chemistry principles at work here.

You assume that because butanes boiling point is lower than room temperature that it all immediately boils off.

The only form of "evidence" you have come close to providing is trying to source vague higher authorities, with out offering any real explanation of it yourself. You are the one saying that all the information is out there, but yet can not address any of the issues brought up nor source any specified information.


The link I posted earlier in the thread is actually an interview with a chemist.
a chemist who specializes in the exact subject we are talking about.
He says nothing close to what you are implying he might, in fact the complete opposite.


No one said or implied that butane has a will of its own and can or will do anything deliberately.

what has been said about BHo and butane contamination:
-butane can become trapped and saturate the oil
-low pressure lowers boiling points
-most oil(tested by these chemist you keep mentioning)tests with butane. Even BHO considered very "clean".
-vac purging increases the likelihood that you will have a lower butane content, but does not guarantee it. if done incorrectly it may not make much of a difference.

I've already provided an interview with a chemist that clearly, with out any question, states that he regularly sees oil contaminated with butane as well as other impurities.

The fact that a single test of butane contaminated BHO exists is evidence that butane will be trapped in the product.

I'm not the one that needs to back up what I say....
 
I think there's very simple thermodynamic and chemical reasons for residual butane and other impurities, despite boiling points. Let's use the early genius of testing lead levels in the environment through ice cores... when a substance crystalizes (especially in kinetically favorable conditions, say... room temp THC/CBD oil) it crystallizes with gases still trapped inside the lattice. Increasing the temperature (heat) and decreasing the pressure (vacuum) allows the product to become viscous enough to allow the gas to become mobile within the semi-liquid state; the vacuum allows the partial pressure of the butane to be siphoned off, as well as as decreasing the boiling point. This is important because even the some of the lowest vaporization temperature gases (like nitrogen and oxygen) will maintain a consistent concentration in liquids due to the partial pressure at the surface of the liquid. One method (heat or vacuum) alone may not be enough, thus the low-heat vacuum machines. These are scientific facts, you cannot argue that a gas simply disappears from a solution because the temperature is much past it's boiling point (as every dissolved gas in water would tell you). Purging is a pretty responsible step to take unless you truly let the residue dry in the sun during the summer for ~ a week

Thank you! That's an excellent explanation.
 
I'll just add due to the complex variety of compound in BHO or any solvent extracted oil heating it will help evap, but butane pockets definitely get trapped. Ever seen BHO that freezes solid, but then melts and forms little holes like gas escaping? That I've always assumed are solvent pockets escaping. I'm obviously talking about something more noticeable with lower grade BHO although I can recognize it easy knowing what to look for. This is really more hypothesis than anything although it makes sense butane could get trapped surrounded by THC molocules it can't push past.

Whipping is the obvious solution to releasing solvent, but probably leads to a lot more terpene loss and whatnot as your exposing as much BHO to the air to release any pockets of solvents. Thinning it out works well too as if you could get a flat layer of molocules (damn near impossible I know) they can release easier vs a big pile of molocules.
 
this is the crux of this issue. if everyone believes that purging is absolutely necessary then it becomes necessary for any company hoping to compete in this niche to invest in the equipment. suddenly there's a strong incentive to keep promoting the notion that purging is worthwhile, because it protects the position of those who are invested in it.



i'm not sure how much the solution raises the boiling point of butane, i'm using the low boiling point to emphasize that butane is a solvent inclined towards being a vapour rather than a liquid, so while vacuum purging increases the rate at which that normally happens, there is no evidence that vacuum purging actually does anything more than just help the natural process along.



i leave my dish out in the open too, the wind is my vacuum chamber and the sun my oven! this sort of anecdata doesn't mean anything without knowing the total batch volume or surface area or ambient temperature because all those factors will affect the evaporation rate.



with no evidence, and not even being able to articulate why you think BHO is so special that it entraps errant solvent molecules, you think it's justified to call it settled?

i don't think it's a settled issue even though i strongly suspect it's bullshit. if finding any credentialed chemist and asking them to verify is infeasible, alternatively i can suggest looking at the vast tomes of research related to this very common procedure (A/B extraction) and specifically what is related to [pure] non-polar solvents (e.g. butane, xylene, toluene, acetone) and if you can find a single shred of evidence to support what you say then there will be some justification to draw conclusions but until then all we really have are the words of people who have clear incentive to make vacuum purging look good because it means profit for them.
You can clearly taste that its harsh as fuck and not as tasty if you smoke some before you purge it... I feel bad for your lungs if you really dont do anything to purge it like that
 
Everyone I know vac purges but I didn't really get that hard into dabs...definitely not enough to manufacture dabs. I think there is a general "better safe than sorry" attitude among my friends who make shatter, but they're not professional chemists or anything. But just a cursory glance shows that you can make shatter either with or without vacuum purging. If I were you, I'd just go the safest route, even if it seems like a pain.
 
so i talked with the chemist in my family recently, he worked in food production and said organic solvent residue is definitely a thing, he wasn't able to say anything about butane specifically but it sounds like i was wrong about that in general. i did a bit of googling looking for a lab to confirm but only found this one in washington state, which claims that:

Often the solvents used are not completely removed by purging with vacuum or heating, and so they can remain in the products that are smoked or inhaled by users in appreciable quantities.

so still nothing conclusive. the big questions are left unanswered, like what effect x amount of vacuum has and whether heating as well helps the situation, or even whether alternatives like agitation could achieve the same results as vacuum or heat. seems like the only thing for sure is that solvent residue does remain in the product, but if that's still true of product that has been heated and vac purged then why is it still so hard to find data that shows the efficacy of the techniques?
 
Yes as others are saying there is definitely a residue left, no matter which brand of butane you use. Try smoking a bit of unpurged stuff on its own and it's very harsh (in a different way to ripping a bong of weed that's too dry type harsh, more nasty IMO) and not very pleasant.

You can leave BHO at room temp for a month. And still get a test back of 5000PPM.

Sorry thujone but some of your posts in this thread are quite ridiculous. Spouting that you've posted proper credible sources to back up your argument. Do you honestly think you as one man know better than all these people who are involved in it at a high level making millions who have all the testing facilities available to them? I've read your posts in this thread and it all comes across as just pig headed arrogance.

They don't just purge it because everyone else is doing it, they do it because the shit is full of gas which is dangerous to your health.
 
i've just never seen a need to purge BHO, in years have never had any harshness or health side-effects, and i'm still waiting on data that actually shows how effective vac purging is.
 
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i've just never seen a need to purge BHO, in years have never had any harshness or health side-effects, and i'm still waiting on data that actually shows how effective vac purging is.

if your chemist friend is even an authority on the subject, he is by no means the only one. By your own admission he can give no certain answer, so it seems even funnier that you are here disputing an entire industry practice.

we are talking about a product that in some cases is worth far more than gold by weight. It's not some underground market anymore, there are tons of highly educated people working in the legal cannabis industry. I'm sure the number of chemist now employed directly by the cannabis industry is in the hundreds.

I don't mean to attack you personally, but it's reckless to go around spreading false information that is potentially damaging to others' health, especially with such confidence and apparently absolutely no evidence or reason other than mere skepticism backing your argument.

To explain to anyone who is truly wondering why vac purging is done, here are a few reasons:
-lowering pressure lowers boiling points
-applying gentle heat ensures boiling points will be reached
-applying gentle heat allow for the product to expand and thus increase surface area
-greater surface area allows for more unwanted gas to be boiled off
-greater surface area means less chance of trapped gas or pockets
-greater surface area ensures a more consistent end product

I don't have a degree in chemistry nor claim to be a specialist in the subject. This is all information I have gathered from my own research, listening to countless BHO and oil manufactures, talking to dispensary owners, talking with many different bho makers who use many different set ups and have a range of problems as well as success, lab tests, and some first hand experience as well.




All that aside, I am really curious as to what is the difference between good and bad oil in your mind. What would cause some BHO to have way higher concentrations of residual butane if butane self purges and the purge process is a farce>

Really, if you could explain to me at all how butane self purges, how it is impossible for it to become trapped, or how it is possible to have chemist show positive test results when screening for butane and still have your theory hold true... i'd love to hear it. I'm sure every one in the industry, except maybe vac oven manufacturers, would love to hear it to. You could probably make a fortune running a consulting company if what you claimed where even halfway true.

The truth is, it's not half as simple as you seem to insist that it is.
 
did you miss where i said i was wrong about butane residue? i'm not insisting on anything except the need for more facts. so far really only two things are clear:

1) butane residue is a thing
2) vac purging removes some amount of impurities

it's the "some amount" that bothers me. what is some amount? how many ppms poses a health risk? how was the 500ppm standard established? how does purity correlate to the amount of vacuum applied? does heating or agitation reduce or entirely mitigate the need for vacuum? these questions are still up in the air and the answers are really worth having.

i would not have claimed no residue remains if i didn't think it was fact. i learned how to do BHO in the chem lab doing A/B extractions and tests that would have shown solvent residue were always negative. making BHO myself, I never had any experiences that would have suggested the product was in any way contaminated. i went out of my way to confirm with someone and post here that i was wrong specifically so that nobody would be mislead into thinking BHO is completely clean, if there is anything else i was obligated to have done to clear up this issue then i don't know what it is.
 
well my kind of educated guess is that if the butane used to extract was of highest (purest) quality, and gets purged, the miniscule amount remaining in the hash oil will probably do nothing. butane is not that toxic really.

smoking the equivalent amount of bud in one go (bong for example) will probably be more hazardous to your lung than a dab with traces of butane.

this is just my opinion though.
 
well my kind of educated guess is that if the butane used to extract was of highest (purest) quality, and gets purged, the miniscule amount remaining in the hash oil will probably do nothing. butane is not that toxic really.

smoking the equivalent amount of bud in one go (bong for example) will probably be more hazardous to your lung than a dab with traces of butane.

this is just my opinion though.
Exactly yoyr opinion it has no factual evidence and doesnt even sound right. Of course butane is toxic and any butane inhaled is absilutely worse than inhaling marijuanna smoke (completely non toxic)
 
that's why I said "not that toxic". if hash oil is purged, the remaining amount of butane is probably so low as to be basically negligible. also, every time you light your bowl/cigarette/joint/whatever, you'll be inhaling the combustion products of butane (mostly CO2, water, some traces of other stuff) as well as a little bit of unburnt butane. there is a difference between inhaling trace amounts and large amounts (eg sniffing).

and yeah I still think that ripping a big bowl of weed will be more harmful to your health (especially lungs) than smoking a little dab with traces of butane. byproducts of plant matter combustions are carbon monoxide, fullerenes, tar, heavy metals enriched in the plant matter, and a lot things more. tobacco for example is known to enrich lots of radioactive nuclei, and cannabis will do the same thing at least to some degree. burning a simple molecule like butane (which is probably over 90% pure, even when low grade) will burn much cleaner.

so I would definately not say that marijuana smoke is "non toxic" when compared to tiny amounts of a simple hydrocarbon.

if you want to bash my opinion, either make better arguments or bring a source (also funny that you critisize me for not having a source and then doing the same thing).
 
Exactly yoyr opinion it has no factual evidence and doesnt even sound right. Of course butane is toxic and any butane inhaled is absilutely worse than inhaling marijuanna smoke (completely non toxic)

I think this is the key point here. Butane probably isn't going to kill you no, but those of us who use weed as medicine don't want any contamination whatsoever, particularly when the contaminant is something much more toxic than weed.
 
I think this is the key point here. Butane probably isn't going to kill you no, but those of us who use weed as medicine don't want any contamination whatsoever, particularly when the contaminant is something much more toxic than weed.
Weed isnt toxic besides the irritation the smoke causes to ur lungs.
 
that's exactly the problem, so many people believe it that they think it's truth. if someone wants to waste their time purging that's their prerogative, if they're skeptical that it's pointless then i'll just repeat what i said the last time: GO ASK A CHEMIST!

wow, you are so wrong on this subject and yet you are ridiculing the SWIM. Purging in a vac oven is the only way to remove anywhere close to an acceptable amount of solvent. Check out Tokecity, skunkpharmresearch, or redit for better information on vac purging.
 
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