Experiments in single-hit micro batches - hexane and White Rhino

[dannite]

For reasons external to this discussion I am trying to learn how to quickly and easily make one-hit batches of cannabis oil/wax/budder. Here is my first attempt.


I started with a medium test tube with about 2 large bowels worth of White Rhino from a Sacramento area dispensary. Sorry, I don't have a scale yet, soon I'll post a batch that is all weighed out and documented. Then I covered the herb with hexane using an eyedropper. This isn't really a how-to so I'm not going to insert all the normal hexane handling warnings. If you haven't heard of using hexane don't worry - its cheaper than using butane, and the vapors are not problematic in the quantities you see here.

Then I put the test tube in a beaker of water set on a normal pancake griddle turned all the way up. This resulted in a beaker about as hot as you can stand to put your hand in - don't know the temp. Gotta get another thermometer - dropped the last one in a batch of hash oil and it doesn't work anymore.

This water temp turned out to be right around whatever the boiling point of my bottle of hexane is (hexane comes as differing blends of isomers so the boiling point is not consistant), because placing it in the water bath caused the mixture to boil within 5 seconds.

Also you see the makings of a chocolate/orange/cranberry cheesecake. mmmmm

Then I poured the liquid into a funnel and filter paper.

I did this process three times - adding more hexane, quickly bringing it to a boil, and then dumping into the funnel. Quite a fast process other than the funnel filter time (I need a vacuum pump or to build a french press setup). After the third time I dumped the damp herbs into the funnel as well and squeezed the herbs through the paper to get the last bits of oil into the beaker.

That resulted in this:

I set that on the griddle and boiled off the hexane. Part of the way through I forgot that hexane vapor is heavier than air and that if you don't periodically blow away the accumulated vapors, they won't evap. Remember that or it will never evap.

In the end I got this:

When I scraped it I got this:

That amount is a small hit. If I had more patience and scraped out the bloody beaker properly it would have been one big hit. With batches this small I need to find a better condensing vessel that I don't lose so much in because I can't scrape it well.

I vaped the stuff on a titanium griddle. My "lung spectrograph" says its 90%+ and it vapes away with no visible residue, so I think the purity is quite high. The taste isn't amazing, but then I don't really know the strain so I don't know what I can tell from that. There was a barely noticeable hint of a smoke taste, so that may have been some trace impurities.

And then I had to mix cheesecake filling with my bloody hands because someone lost the beater to my kitchen aid. The upside is that my hands are now moisturized and smell of fresh orange zest and vanilla paste.

Anyway, here are some questions I am thinking over, so feedback would be awesome:

1 - Note that my product went from golden/yellow to dark, almost black when I scraped it off. Why is this?

2 - There is an barely-discernable green tinge to the oil as you can see. I assume this represents impurities. What might be the source? Do I need a finer filter paper, or is that maybe from water coming from starting with herb that was not perfectly dry?

3 - Any ideas on what to use as a filtration/evaporation vessel? Something that would allow me to easily get ALL the product out. It could even be plastic because the temps involved are so low.

4 - I was a little surprised by the consistency. I expected oil, and then to whip it into budder. What I got was putty. Is this because of the way I evaped the hexane on the griddle? Maybe I "cooked it" a little making it go more solid? I am unsure of the chemistry with these materials at this temp. Does anyone out there have a source of knowledge on what makes high purity concentrates take different forms?

 

[jdee]

1 - the longer or higher you heat it, the darker it gets
2 - the green is chlorophyll, the longer it sits in the solvent, the more there will be generally
3 - toaster ovens are amazing for purging bho, could be worth a try
4- not sure about this because your using hexane, but I know that with butane the end consistency is mostly dependant on purge temps, lower temps will be more taffy like and higher temps will be like hard glass

 

[dannite]

So take home message is doing everything at a lower temperature and higher speed would make it more runny and more clear?

The spectrum you mention is taffy on one end and glass on the other. Where do you get oil you can drip or put in a syringe? This form of oil would seem to me to be the ideal product to perfect because it is the pure starting form of all high-potency concentrates.

 

[AGBeer]

One thing that I see in common with (a good portion) of common extractions is low temps.

Compressed butane gas = Friggin cold.
Supercritical CO2 extraction = Friggin Ccccccccoooooold
Many a peoples ISO washes = Cold


The general consensus of some of the bigger time (other) solvent makers is to freeze their product as well as their solvent prior to extraction. This reduces the amount of chlorophyll that is extracted in the process.

Might be something to take into consideration

 

[stroh]

you will never achieve oil that you can drip from a syringe, unless it has been heated to a molten consistency, or still has a highly unsafe amount of solvent left in it. I don't understand why one would want to perfect a runny consistency, as it is much harder to work with, and sticks to everything, causing you to lose much of your precious oil to the sides of your storage container/dish.

as for lighter and more clear oil, the first thing you should NOT do, is grind your nuggets, in fact never grind your herbs before any extraction unless you are running previously ran buds. This will drastically reduce the amount of chlorophyll and plant contaminants. the second thing you SHOULD do, is reduce your soak time. I also do not understand the point of boiling the hexane/herb mixture, what is this supposed to achieve? Next time, soak your product in the hexane, filter it into a pyrex, then evaporate. i see many unnecessary steps of adding more solvent to the already hexane'd buds, after the first and second wash (which should be done separately, and after the herbs have been dried out.) anything remaining on the buds is purely contaminants, any psychoactive compounds are negligible as most have been extracted.

good luck with future extractions, i'm curious as to how hexane performs, and i believe it is reclaimable as well?

 

[dannite]

you will never achieve oil that you can drip from a syringe, unless it has been heated to a molten consistency, or still has a highly unsafe amount of solvent left in it. I don't understand why one would want to perfect a runny consistency, as it is much harder to work with, and sticks to everything, causing you to lose much of your precious oil to the sides of your storage container/dish.

A agree that working with a thin oil would be more difficult. I am just trying to consistently hit that for a reference point so that I can intentionally divert from that state into others, instead of just go straight to what I ended up with this time.

as for lighter and more clear oil, the first thing you should NOT do, is grind your nuggets, in fact never grind your herbs before any extraction unless you are running previously ran buds. This will drastically reduce the amount of chlorophyll and plant contaminants.

What you are saying makes sense, and I have heard of people just using the outside of buds so they get a super pure and potent product. However, most guides I have seen do indicate to grind very finely for iso, hex and tane extractions.

the second thing you SHOULD do, is reduce your soak time. I also do not understand the point of boiling the hexane/herb mixture, what is this supposed to achieve? Next time, soak your product in the hexane, filter it into a pyrex, then evaporate. i see many unnecessary steps of adding more solvent to the already hexane'd buds, after the first and second wash (which should be done separately, and after the herbs have been dried out.) anything remaining on the buds is purely contaminants, any psychoactive compounds are negligible as most have been extracted.

good luck with future extractions, i'm curious as to how hexane performs, and i believe it is reclaimable as well?

I was boiling as an alternative to soaking for an extended period of time. You are probably right about the boiling.

I soaked multiple times because of the guide I was referencing. I think it is probably correct, as the second and third extractions both came out golden. That would imply that there is active product still being pulled out.

The hexane is reclaimable if you are condensing it. A condenser rig is pretty impractical until you get to rotary evaporator levels of production though.

 

[stroh]

i suppose if you are shooting for a high yield as opposed to a more pure product, multiple washes and grinding will definitely get you there, however i feel that this tradeoff is a double edged sword, as most of the added yield is from contaminants. i would rather create the purest product i can, but hey different strokes for different folks. I see now what you are getting at with the reference point, i think this would be pretty difficult to do, as different strains will posses different viscosities and surface tensions, and may require changes in your usual purge tech to achieve your desired consistency. I suppose reclaiming the hexane would be more trouble than its worth unless you were doing massive extractions, but thank you for that information, did not know the details behind it all. having never worked with hexane, i would not be able to tell you how correct that guide is, but i feel that most extractions are pretty similar, just the properties of the solvent used that have the most drastic changes.

 

[weedemon]

thanks for doing this and documenting it for us! i was very interested in hearing this.

in fact i was sure i posted a reply here already but i remember being very vaked, so maybe i didn't submit it. lol

im surprised that the flavour is not there, I thought because this is also a non polar solvent that it would be more like bho and flavourful.

so overall how impressed are you with this extraction? worth it over butane?

is hexane available in a pure form? 100%?

thx again for posting this run man!

 

[dannite]

I'm not sure why it doesn't taste good. It's not that amazing of herb. I only used a few grams, so I have plenty left to try controls with butane and compare. I'll also do a fresh hexane batch and take it slower on the vape off and faster on the steep so it's less brown. Maybe a colder extraction will make it taste better.

Overall I like the process. Hexane is easy to work with and precisely control. My eventual goal is to be able to pull off this process in 5 minutes or so for a single hit - espresso machine style using only a warm water bath to speed vape off. However, I am designing a rubber piston that I can use to create a strong vacuum in the tube, allowing me to force the hexane to flash vape which should get me down to a minute or two to get a fresh hit of honey oil from dry herbs.

With this as my stated goal, I hope I can get a good tasting product from the hexane, because I don't think I can get my final vape off as fast with butane because I am pretty sure I can get away using less volume of hexane than butane because of the way hexane can sit and steep in the same solvent, while butane is normally blown through material picking up fewer plant goodies per ml than the hexane.

Of course I may have it backwards, maybe even with the larger volume of solvent the butane is faster because of its far lower boiling point. I'll have to experiment.

If it turns out butane becomes nescessary for quality taste reasons and the solvant volume thing is an issue I can build another piston that will allow me to increase the pressure inside the tube to the point that the butane condenses. This would allow me to steep in liquid like with hexane giving me the smaller volumes of solvent I am after. If I could get my solvent volume down to several ml per gram of herb of butane I could prolly vacuum vape the whole of it out on a single piston pass.

The main disadvantage I see to this system is that while hexane can be recovered with a simple water cooled hood, the butane is un recoverable by reasonable means. This is no big for a single hit batch, but if I wanted to "cannabarista" out a dozen batches in sequence the vapor could start to be dangerous.

Alternatively I could prolly skip all the engineering if I just used dry ice to cool my butane to a liquid point and then work with it just like the hexane, giving me all the benefits of cold extraction, the ease of working with liquid instead of gas, and the final vape off speed of a sub zero boiling point and low ml/g solvent loads.

 

[dannite]

Oh, you asked about reagents purity. I couldn't easily find food grade hexane, but what I have is 99+% pure. The guy says that they take the food grade and reagent off the same distillation point, they just test and certify the food grade.

 

[DaProfessor]

Just dropping in for a tip that I picked up from somewhere. I totally forgot, so yeah...

You might be able to improve recovery by changing the consistency from a gel to a solid. I heard that you can change the consistency of BHO from a wax/butter to glass via repeated temperature cycling. As in heating->cooling multiple times until you reach the state that you prefer. Might be worth a try

Edit: If you want to go all out with cooling, you can can create a cooling bath of acetone/dry ice for a cool ?78 C. Wish I had access to more herb so that I could do these experiments myself

 

[High Sigh]

I think this would be much better with butane, and a TINY extraction tube. A squirt of butane would be all you need.

 

[dannite]

I actually ended up trying this. I picked up some 25ml plastic syringes and did a few grams in there with butane. Once I squirted the butane gas in there, I plugged the syringe and rammed the plunger. This made enough to condense the butane into liquid and steep the herbs completely. I still need to refine the system a bit, but I am getting super small batches with small solvant loads. Quite promising.

 

[dannite]

Just dropping in for a tip that I picked up from somewhere. I totally forgot, so yeah...

You might be able to improve recovery by changing the consistency from a gel to a solid. I heard that you can change the consistency of BHO from a wax/butter to glass via repeated temperature cycling. As in heating->cooling multiple times until you reach the state that you prefer. Might be worth a try

Edit: If you want to go all out with cooling, you can can create a cooling bath of acetone/dry ice for a cool ?78 C. Wish I had access to more herb so that I could do these experiments myself

Yah, I ended up deciding that I want to use butane for its heightened selectivity. The problem is that butane steeps the herb most efficiently as a liquid, and as you mention, cooling is the way to liquify it. The other way is of course increasing the atmospheric pressure acting on the sample. So at the moment I am experimenting with pressure methods since that seems easier. However, I am considering trying the cooling method as well. Could be fun to play with liquid butane.

 

[DaProfessor]

The heating/cooling cycle was meant to be applied to the extracted product, not the solvent. Try cycling the extract after evaporating the hexane. My guess is that cycling the temperatures helps to align the crystaline macro structure of the extract, like tempering chocolate.

If I understand correctly, you are going to try to use the acetone/dry ice bath to help keep the butane liquid? Might work. Good luck, stay safe and report back with your findings

 

[notmyrealUSERname]

Just dropping in for a tip that I picked up from somewhere. I totally forgot, so yeah...

You might be able to improve recovery by changing the consistency from a gel to a solid. I heard that you can change the consistency of BHO from a wax/butter to glass via repeated temperature cycling. As in heating->cooling multiple times until you reach the state that you prefer. Might be worth a try

Edit: If you want to go all out with cooling, you can can create a cooling bath of acetone/dry ice for a cool ?78 C. Wish I had access to more herb so that I could do these experiments myself

Yah, I ended up deciding that I want to use butane for its heightened selectivity. The problem is that butane steeps the herb most efficiently as a liquid, and as you mention, cooling is the way to liquify it. The other way is of course increasing the atmospheric pressure acting on the sample. So at the moment I am experimenting with pressure methods since that seems easier. However, I am considering trying the cooling method as well. Could be fun to play with liquid butane.

If you want to play with liquid butane I would suggest that you do a lot of research about the tasmisium extractor. It's a well designed, proven extractor thats compatible with n-butane (99.5% pure), and you can recover almost all of your butane every run which is done by temperature differentials in the extraction and recovery tanks. Its designed to extract much larger quantities than your after of course, but then all you have to do is make it smaller.

Also, I would suggest looking into vacuum pumps. Instead of condensing your solvent with 'compression', by your plunger system, a vac pump will use negative pressure to do the sane thing your after much more effectively.

 

[dannite]

Thanks for pointing me at the Tasmisium extractor. Seeing the design on that was helpful. However, it doesn't meet my needs. I am working on a design that will be far simpler to use and allow for single batch cycles in a minute or two. I am working through a design that uses pistons and levers to make both vacuum and pressure. I'm getting a membership at one of those workshops they have in the area where I get access to manufacturing equipment for a monthly fee. I have a background in manufacturing, so I should be able to make the engineering work. I'll keep 'yall up to date.

 

[druminfected]

When you did it with Hexane you weren't spose to put it in hot water to boil it. I think this is the step process that messed it up and like you said you "cooked it"

 

[stroh]

i really do not understand why you don't fashion yourself as simply extraction tube, as the pressure is high enough in a super critical fluid extraction to cause the butane to remain as a liquid throughout the extraction process...

 

[dannite]

Heh. That is what I have been up to... I am pretty close to the cannabis answer to the espresso machine.