CBD Extraction Methods
With the wide choice of products available on the hemp market, many are getting curious about trying out new methods to create better and stronger products. In order to increase quality and potency, many use CBD extracts when creating their products. But how is CBD extracted? Below, we will explore the various CBD extraction methods.
Solvent-Based Extraction Methods
You may extract CBD from plant material using solvent-based and solventless methods. Solvent-based extraction methods require closer monitoring and control due to chemicals and complex equipment use.
Using sophisticated technology and equipment is crucial in the hemp industry, especially for solvent-based extractions. Generally, manufacturers most often use ethanol or butane for their solvent-based extractions.
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Ethanol extraction
Ethanol is the most common method for extracting CBD. Ethanol is a safe and efficient extraction method as the solvent is also used as a food preservative. Moreover, the FDA considers ethanol a 'generally safe' substance.
Another reason for the widespread use of the ethanol extraction method is its cost-effectiveness. Ethanol is a polar solvent that can dissolve cannabinoids, terpenes, and water-soluble molecules.
Manufacturers may perform ethanol extraction at various temperatures to achieve different effects. As such, there is warm and cold ethanol extraction. Warm ethanol extraction is easier, but removing the unwanted compounds from the end product is more challenging.
In contrast, cold ethanol extraction may increase yield while minimizing waste and reducing cost. All the unwanted materials are frozen with cold ethanol extraction, making removal easier.
Hydrocarbon extraction (butane, propane)
Hydrocarbon CBD extraction involves using solvents like butane and propane. The rising popularity of the hydrocarbon extraction method is because of the high quality and purity of the CBD extracts.
Manufacturers use hydrocarbon extraction methods because they can avoid unwanted water and chlorophyll. The hydrocarbon extraction process requires placing the plant matter in a container where it is flushed with the chosen solvent.
The hydrocarbon method is considered more dangerous because of the high flammability of the solvents. As a safety precaution, manufacturers use closed-loop systems.
Solvent-based extraction process equipment
In order to extract CBD from cannabis plant materials, you must use the appropriate equipment for their extraction method. The following materials and equipment are required for solvent-based extraction:
Plant material
Appropriate solvent (ethanol, butane, or propane)
Solvent containers
Inline extractors
Closed-loop extractors (for hydrocarbon method)
Filters (mesh screens)
Vacuum pump
Solvent-based CBD extraction process
Like with any other extraction method, the first step is choosing a cannabis flower strain and its preparation for the primary extraction. It is crucial to choose a high-quality cannabis flower to get a refined CBD extract.
Primary extraction
During the primary extraction step, the manufacturers place the selected cannabis flower in a solvent container. In the container, the plant material is mixed with the chosen solvent to separate CBDa.
Depending on the solvent used, CBD extraction happens at different temperatures,
Cold ethanol CBD extraction: -22˚F (-30˚C) and -40˚F (-40˚C).
Butane CBD extraction: -1.4˚F (17˚C) and -108.4˚F (-78˚C).
Propane CBD extraction: -23˚F (-5˚C) and -40˚F (-40˚C).
Decarboxylation and purification
After extracting the wanted compounds from the plant material, it is time for decarboxylation. The extracted mix is heated under a vacuum during this step to convert the CBDa compound into its active CBD form.
The heat also purifies the extract because the solvents evaporate due to the high temperatures. Besides safety, most manufacturers use closed-loop extraction equipment over open as the high pressures allow for maximum cannabinoid extraction.
Distillation
The final step after activating the cannabinoids and removing the solvents is distillation. The extract reaches specific boiling temperatures during distillation, turning it into vapor.
The vapor is then passed through a chilled condensing head to turn it back into a liquid form. The end result is a CBD extract free of any residual chemicals.
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CO2 extraction
Compared to other extraction methods, CO2 is said to be safer and cleaner. The system is typically more expensive than ethanol or hydrocarbon systems, resulting in a larger initial investment for manufacturers.
Subcritical vs. supercritical CO2 extraction
Subcritical refers to CO2 extraction at temperatures below 83˚F. In contrast, supercritical CO2 extraction reaches 87.8˚F. So, as subcritical CO2 extractions work with lower temperatures and pressure, the process requires more time and produces smaller yields than supercritical.
But, the high pressure and temperature of the supercritical CO2 process damage most terpenes. In contrast, the subcritical process retains the terpenes and other heat-sensitive chemicals in the plant material.
Benefits and efficiency of CO2 extraction for CBD
Environmentally friendly
The CO2 extraction of CBD is more environmentally friendly as it traps the carbon dioxide gasses instead of releasing them into the atmosphere. Manufacturers adjust their working practices to meet demand as more users search for environmentally conscious brands.
Safer
Unlike hydrocarbon solvents (butane, propane, etc.) with CO2, there is no risk of combustion. Propane and butane are flammable solvents, so they must be closely monitored. In contrast, with CO2, you may need a carbon dioxide monitor for potential leaks.
Long-term cost-effectiveness
The CO2 extraction process is more cost-effective for manufacturers in the long run. As the gas is trapped, it gets pushed through a condenser, which liquifies the gas again. Manufacturers can reuse the recycled gas for future extractions.
CO2 CBD extraction process
CO2 does not mix well with water. When mixed with water, it separates from the extract and lowers the yield. To fully dry the plant, you can either hang it up to dry or put it in an oven.
If you are in a humid location, you may use a freeze-dryer to remove all the moisture. The plant is pulverized to the consistency of coffee grinds once it has completely dried. After that, it is put into the CO2 system's extraction chamber.
The extracted oil is much more effective than other products since it is highly concentrated. The extracted oil can be used in many items, such as tinctures, balms, edibles, and vape pens.
Solventless extraction methods
Solventless CBD extraction does not involve the use of any chemicals. Without the use of any solvents, these methods are safe to try out yourself. The CBD extracts created with solventless extraction methods have high cannabinoid and terpene profiles.
Rosin
Since it is pure, strong, and tastes good, rosin is one of the more widely used solventless cannabis extracts.
Commercial rosin heat presses can handle large quantities of plant material pressure. These are an industrial alternative to using a hair straightener or a heat press at home to make rosin dabs.
The viscosity of rosin is typically similar to that of shatter. However, it can also be produced in various textures that mimic other extract types, such as crumble, budder, and wax.
Dry Sift
Dry-sift kief is manufactured by sifting fresh and dried flowers or trim across various mesh screen filters.
You can shake dry sift kief by hand or use a machine to stir it around over mesh screens. You can add the resulting kief powder to edibles, pre-rolls, or create hash for dabbing.
Ice Water
As the name suggests, you place the plant material in an ice-water bath. Once you submerge the cannabis buds in the freezing water, you should stir it so the wanted components separate. Afterward, you must pass the mix through several screens to filter the needed components.
Factors Influencing CBD Extraction
When extracting CBD, the starting plant material plays a vital role in determining its quality. You must choose a high-quality cannabis strain from which you want to extract cannabinoids.
Also, a deciding factor in the potency of the CBD extract is which part of the plant you decide to utilize. For instance, using cannabis flowers produces a higher yield. But trims offer more concentrated extracts.
Other factors influencing the extraction efficiency are the following:
The extraction method (solvent-based or solventless)
Which solvent you choose to use (butane, propane, CO2, etc.)
Extraction time, pressure, and temperature
Moreover, the CBD extracts must be purified, especially when created with solvents. The solvent chemicals are harmful, so before the extract is finished, they must be purged from it. Manufacturers use lab testing to ensure their CBD extracts and products are clear of residual chemicals and comply with regulatory laws.
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Conclusion
Several CBD extraction methods produce high-quality CBD extracts. CBD extracts' potency, quality, and quantity depend on which extraction method is used. There are solvent-based and solventless methods to extract CBD, so it’s up to you to choose one that would work best for your needs and preferences.
