by Rien Havens, PhD (CTO) Really Helping, PBC

This is intended to update the last article on the many methods of extraction for industrial hemp. I spent a lot of time at the last Cannabis trade show, talking to vendors and extraction experts with lots of different types of equipment. I see that one of the biggest problems to progress as an industry as a whole is contingent upon the community having as accurate as information as possible. I do understand that in some people’s minds, this could put me and my efforts at processing at a competitive advantage, because the competition will benefit from this. From my perspective, this is a small price to pay to educate the industry with the best information possible. I would also like to stress that an industry benefit for openly sharing information like this is it allows more farmers and individual businesses to benefit from the Industry. From my perspective, we need lots of innovators making end products to help people, and to create more demand in the market for this great industry. To this end, I feel that if I can empower more small farmers to be able to product higher end raw material, and this means being able to sell individual Cannabinoids or high quality extracts at a reasonable price. Hopefully this will help create a more equitable profit sharing and cooperation based model in the industry, which I would like most to support smaller, localized, organic farming. So much of this article is, in a way, with those motivations as a backing: transparency, accuracy, and with cooperation and innovation in mind.

CO2_Extractor_RienAt the Cannabis conference in Las Vegas, I spoke to people selling CO2 equipment, but also discussed a high volume alcohol processing system, and some passive closed loop solvent systems. I didn’t get the kinds of answers that I wanted from the CO2 extraction teams. Regarding the energy usage, the most fuel efficient of the CO2 systems still would pull 5 220V, which is still enormous. The second issue with CO2 has to do with the material forming carbonic acid, and rotting the material, which creates carcinogens and toxins, and can encourage bacterial growth. There weren’t adequate answers to that question, either. Most claimed to ‘recycle’ the solvent, but I saw none that addressed the fact that water and carbonic acid forms within minutes of the CO2 entering the extractor, and this problem gets worse when the solvent is recycled.

So that leaves the producer with two options: first, they can discharge the solvent, which is already extracted from crude oil products. So CO2 is really not much different than butane from that perspective, they are both products of crude oil. Second, they can recycle the solvent, and if they do that, they have to dry the product to such a degree that there is extensive essential oil loss, which has major medicinal benefits. If they do not dry properly, the product will rot right in the extractor and this causes potentially carcinogenic rancid fats to form in the extract. The last problem is the potential concentrations of carcinogens from pesticide use. There have been extracts that have been coming back hot for pesticides and heavy metals recently, and without knowing that the flower comes certified organic, there is no way to know whether the extracts are coming back toxic or not without testing them. This needs to happen, as there is no regulation right now surrounding processing, which can be a concern for consumers. I am not sure right now who is and who is not testing, but I have for a fact seen some product come back rancid, toxic, and with contaminants. We need to focus our purchases on companies with transparent chain of custody practices with their flower and lots of testing for contaminants both in the initial flower and final product. Take a test for yourself to Centennial Seeds or another testing agency and ask for pesticide and contaminant testing. If it’s CO2 oil, before you buy a quantity, make sure to test for rancidity.

Lastly was the cost vs. throughput. Whereas the alcohol or solvent based system can produce 100+ pounds per hour at about 100K, the CO2 extractors were able to extract 12-20lbs in a comparable day, with around 300k of investment for the equipment. That leaves the solvent-based systems at 20 times the capacity and volume for the same investment cost. If that was a car, that would make one $30,000.00 car with much better performance, up to twenty times less environmental and energy waste, and a much safer end product, with a price comparison to a $600,000.00 car. I would take the better, more fuel efficient, less dangerous car for $30,000.00.

Cannabinoid_SeparatorMoving on from the difficult CO2 topics, to ethanol extraction. With an alcohol system, we are able to produce a very high volume of full spectrum extract, which includes bioflavonoids and other products. The one main problem is the ‘fatty acid methyl ester’ that is created as a byproduct of the alcohol reacting with the fatty acids in the product. According to the MSDS safety data sheet, ‘fatty acid methyl ester’ is not toxic, and the only concern would be excessive buildup in the product, which with good processing equipment would not happen.

The last is the passive or active closed loop solvent system, used with an alcohol ether or propane, sometimes butane. These systems are relatively inexpensive, and if you get medical grade ether, or butane, you can ensure that the solvent is free from toxins and will leave a clean product. Some people have an issue with the idea of a fossil fuel, but CO2 is also extracted as a fossil fuel, and is expelled after extraction after a single time, if they say they recycle it, then it becomes toxic. Butane on the other hand, can pick up moisture, but will not cause the formation of carbonic acid and will not become toxic after a few uses. From what I have seen, propane is actually the cleanest and can last a hundred times or more with the right equipment before needing to be burned off. So even though it got a bad wrap, it uses much less fossil fuel, is safer, and incredibly cheaper than CO2. I actually prefer the quality of this product to the ethanol extract, but the ethanol is technically more sustainable and does not touch fossil fuels at all for the purists out there, it can also be certified organic in it’s processing. The quality of equipment is just not there in comparison to the closed loop solvent systems, though. We don’t have as much technology available for purchase in the industry for ethanol as we do with closed loop solvent systems.

Rien_and_Alcohol_SeparationThere are a lot of benefits to alcohol extraction. First off, it is not a fossil fuel, and it only uses 110V plugs and is about 1/5 of the energy consumption of CO2. It is also possible to use organic alcohol with the process, which is about as environmentally friendly as you can get. There are a few good alcohol systems out there.

There are two other kinds of solvent-less extraction methods. Heated Press, and Sonication. Heated Press is a great method, and can be used with keif as well for a very nice oil, but since there are no solvents, the oil has much higher levels of fats and waxes, but there is a distinctly fresh taste.

There was one major delight, and that was the success of a THC removal, Cannabinoid separation system that is set up and ready for use. Separating Cannabinoids can be done in different ways, but all involve chromatography, which means splitting up one thing into its different components, much like light being divided into the rainbow through a prism. Hence “chroma” meaning color, in chromatography. There are many ways to do this, but all of them involve teasing the molecules apart using their weights, boiling points, and the strength of the way they ‘stick’ to other molecules. There are some easy and straightforward ways to separate these out that are in the works right now. Stay updated and follow me on Instagram, or find me on Linkedin or Facebook and you can stay in touch. My email is, but quick responses to questions are getting increasingly difficult. That said, I am always happy to get correspondence, I’m here to help please reach out and I’ll do my best to respond.

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