The purpose of CBD extraction is quite simple; to create the cannabinoid (and others) in a highly concentrated form to make it suitable for human consumption. You must use a plant material rich in CBD such as special cannabis strains or hemp.
There are many ways to extract CDB Oil from the Cannabis plant, however we have listed the 4 primary ways, including the SDZ preferred option being the CO2 method
1. The CO2 Cannabis Extraction Method - SDZ Preferred method
This form of CBD extraction is actually divided into supercritical, subcritical and ‘mid-critical’ categories but supercritical is by far the most commonly used. In fact, it is the most regularly used extraction method of all because it is safe and provides a pure end product.
In simple terms, CO2 cannabis extraction uses pressurized carbon dioxide (CO2) to pull CBD (and other phytochemicals) from the plant. CO2 acts like a solvent at certain temperatures and pressures but possesses none of the dangers. While it is safe and effective, it also involves extremely expensive equipment. The rather sophisticated machines used for the purpose work to freeze the CO2 gas and compress it into a supercritical cold liquid state.
CO2 typically behaves like a gas at standard pressure and temperature and is easily changed to a solid while in this state; the solid version of the gas is known as ‘dry ice.’ Using the aforementioned equipment in a lab, you can turn CO2 gas into a liquid by ensuring the temperature drops below -69 degrees Fahrenheit while increasing the pressure to over 75 pounds per square inch (psi). At this stage, you have your starting point for CO2 Cannabis extraction.
Once you have the liquid CO2, the next step is to increase the temperature and pressure past the point where the liquid becomes ‘supercritical.’ This term means the CO2 is now capable of adopting properties halfway between a gas and liquid simultaneously. Effectively, the supercritical CO2 is capable of filling a container (like gas) while also maintaining density (like a liquid). When CO2 is in its supercritical state, it is ideal for chemical extraction because it won’t cause the denaturing or damage that would make it unfit for human consumption.
Regarding extracting the CBD oil using this technique, you simply begin with liquid CO2 and raise its pressure via a compressor. You must also raise its temperature using a heater. The next step involves passing the supercritical carbon dioxide through some high-quality cannabis which should bein an extractor. Now, the CO2 will pull the essential trichomes and terpene oils out of the plant.
The solution gets passed via a separator and broken down into its requisite parts. The good stuff (including trichomes and terpene) is sent to the collection container. Meanwhile, the supercritical CO2 goes through a condenser and turned back into a liquid. Finally, the liquid goes to a special storage tank and can be used to begin the process all over again.
This form of extraction involves low temperature and low pressure. Subcritical extractions take longer than their supercritical counterpart and also produce a smaller yield. While it retains the terpenes, essential oils and other sensitive materials, it doesn’t extract larger molecules such as chlorophyll, omega 3 & 6. Subcritical extraction is less likely to damage terpenes. Mid-critical is simply a general range between subcritical and supercritical. Some companies combine supercritical and subcritical to create a full-spectrum CO2 cannabis extract. They use the subcritical extraction method to separate the drawn-out oil and draw out the very same plant material using supercritical pressure. The oils are then homogenized into one which creates a unanimated oil. This is known as the CO2 Total Extraction Process.
Pros of CO2 Cannabis Extraction
Safety: CO2 is a common food additive and is used to produce carbonated soft drinks for example.
Effectiveness: CO2 has been used as an extraction solvent for years by food companies. It is used to remove caffeine from coffee and as an extraction solvent when producing essential oils. Purity: The cannabinoids produced are potent and free of chlorophyll with minimal risk of contaminants.
2. The Olive Oil Extraction Method
While other liquids such as ethanol can be used in this process, olive oil is the most commonly used substance for this extraction which can be performed at home. The first step involves ensuring the raw plant material is decarboxylated. In layman’s terms, it means you have to heat the plant at a certain temperature for a specific length of time to activate the plant’s chemicals.
Most experts recommend heating at 248 degrees Fahrenheit for 60 minutes or at 284 degrees Fahrenheit for 30 minutes. Once this step is completed, add the plant material to the olive oil and heat to 212 degrees Fahrenheit for up to 2 hours (and at least 1 hour). This process should result in the extraction of the cannabinoids, and ultimately, you should receive oil with the CBD content you require.
Pros of the Olive Oil Extraction Method
Very Safe: You won’t blow yourself up using this method to get CBD!
Inexpensive: You can set everything up at home without breaking the bank.
Cons of the Olive Oil Extraction Method
Perishable: Regardless of whether your cannabis infused oil is high in CBD or THC, it is highly perishable so you must store it in a cool, dark place as soon as possible.
Low Yields: This form of extraction only produces fairly low yields, so there is no possibility of a company using it due to the labor-intensive nature of the method.
3. The Dry Ice Extraction Method
The dry ice extraction method is another method of CBD extraction that can be performed at home although it takes a bit more time and effort than its olive oil equivalent. As well as the cannabis plant itself, you’ll need the following equipment:
- Around 3 pounds of dry ice.
- A large piece of Plexiglas or a mirror.
- A paint scraper or putty knife.
- Thick gloves that are heat resistant and eye protection.
- A clean 5-gallon plastic bucket.
- 3 bubble hash mesh bags; sizes are 73, 160 and 220 microns.
- 3 large, clean glass jars for storage.
Put on your gloves and eye protection, chop up the cannabis plant into small pieces and place it in the bucket. Cover the plant with the dry ice and leave it for 3 minutes; it is best only to fill the bucket halfway; this process causes the freezing of the trichome resins. Fit the 73-micron bag over the bucket and sake the ice & plant combo for around 4 minutes; this knocks the frozen trichomes off.
Turn the bucket upside down on the Plexiglas and shake as much resin through the mesh bag as possible. Scrap the hash off the Plexiglas with your scraper and place it into one of the jars. Repeat with the 160 and 220-micron mesh bags, and you’ll be rewarded with three different strains of extract.
Pros of the Dry Ice Extraction Method
Ease of Use: The steps above are very easy to follow.
Clean: Unlike other methods, there is very little mess with dry ice extraction.
Decent Yield: You’ll end up with a lot more than if you use oil extraction.
Cons of the Dry Ice Extraction Method
Low-Quality: This is entirely dependent on the user, but you will ruin the quality of the product if you shake it for too long.Not Always Easy Getting Dry Ice: Depending on whereyou live, it isn’t always so easy to get your hands on 3 pounds of dry ice unless you order it online.
4. The Solvent Extraction Method
Ethanol, low-grade alcohol, and butane are among the most common substances used in Solvent Extraction. Although ethanol extracts the full range of cannabinoids and terpenes from the plant which makes the end product safe for consumption, it also extracts chlorophyll which may lead to some unpleasant side effects. You can remove the chlorophyll by filtering the extract, but you significantly reduce the oil’s potency. Butane offers a stronger oil than ethanol, but it is more likely to contain solvents which could irritate the lungs.
All you have to do is add the liquid (whether it is butane, alcohol or ethanol) to the plant material. The extraction liquid will strip away the cannabinoids and flavor from the plant material but will probably take some of the green colorings too. Once you believe you have enough cannabinoids in liquid form, heat the liquid to evaporate it down to the CBD base oil.
Pros of the Solvent Extraction Method
Appropriate For Some Products: If you use high-grade alcohol, you may produce good quality oil suitable for vaping cartridges.
Straightforward Process: Once you have the equipment, it isn’t difficult to complete the process.
Cons of the Solvent Extraction Method
Extremely Dangerous: Butane and Ethanol are flammable, so it isn’t worth starting a fire in your home to extract CBD in this manner.
Potentially Harmful: As well as destroying plant waxes, this form of extraction may produce oil that contains chlorophyll or other harmful contaminants.