How to: Cannabis Extraction Methods

Cannabis extract is the result of extraction of cannabinoids and terpenes from the cannabis plant material , such as cannabis flowers . Cannabis extraction is similar to the procedures used to decaffeinate coffee, produce vitamins and minerals, and create essential oils. Since cannabinoids and terpenes determine the effect, the taste and the aroma of the final product, the cannabis extract, producers are looking to extract these two compounds.
The extraction of by-products of various plant species is a process that has been used for centuries.

For cannabis extraction

Two of the primary extraction methods for medicinal cannabis are the so-called supercritical CO2 extraction and ethanol extraction. The method most commonly used is carbon dioxide. Basically, the process is dependent on the conversion of CO2 into a supercritical fluid. This is done by exposure to temperature and pressure until the supercritical, liquid form is reached. At this point, carbon dioxide can act as a solvent. This solvent is then pressed, for example, through an extraction vessel filled with granular medical cannabis material.

Ethanol is often used as another solvent. As a rule, the extraction is faster, but also leads to a different product. Ethanol is more polar than CO2, pulling more chlorophyll, colors and tannins out of cannabis. The difficulty of extracting with an ethanol extract is to remove all the solvent that remains after extraction. As with most extraction methods, an additional step is required to refine the extract prior to incorporation into cannabis products.

The refinement process varies based on the extraction method initially used. For supercritical CO2 extractions, the second step is called winterization. Here, ethanol is used to separate the pure cannabinoids and terpenes from other by-products that are stripped off during extraction. For ethanol, which is more polar than carbon dioxide and thus does not contain the vegetable waxes and fats present in a CO2 extract, an activated carbon filtration process is used to remove instability.

Cannabis extracts as medicine

With a legal extension of the Narcotics Act (BtMG) on March 10, 2017, doctors are also allowed to prescribe medicinal hemp and cannabis extracts in pharmaceutical quality. Like the cannabinoid drugs Sativex , Marinol and Canemes , they are prescribed on dedicated official forms, the narcotic prescriptions (BTM prescriptions).
The effects of the cannabinoids Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) , both of which are found in medicinal cannabis extracts, can be used to treat various diseases. In addition to mental illnesses, such as depression and anxiety disorders, are also included Multiple sclerosis , epilepsy , rheumatism, migraine , ADHD , certain cancers as well as the effects of chemo.

To extract cannabidiol (CBD) from cannabis, there are various extraction methods. CBD is present in the plant as carboxylic acid (CBDA) , a so-called inactive ingredient . The conversion of CBDA to the more pharmacologically effective CBD is called decarboxylation . In this process, a carbon dioxide molecule is split off from the CBDA by heating or by enzymatic catalysis. This process is similar to the decarboxylation of THCA in THC , a process that is achieved by smoking by burning, to release the psychoactive substances.

Currently used methods include extraction by heating, supercritical carbon dioxide, butane, hexane, isopropyl alcohol or ethanol.

CBD DECARBOXYLATION BY HEATING

 

In general, the higher the temperature, the faster the decarboxylation. At a temperature of 210 ° C, almost 100% of the substance can be converted within a few seconds. However, this can be at the expense of terpenes , which also contribute to the pharmacological effect of cannabis.

As evidenced by patents issued by the British company GW Pharmaceuticals , their process involves heating in two stages. In the first step, the plant material is heated to a temperature of 100 ° C to 110 ° C for 10-20 minutes. The residual moisture in the plants is vaporized. In stage two, a temperature of 120 ° C is supplied for the duration of 60 minutes.

CBD EXTRACTION WITH SUPERCRITICAL CARBON DIOXIDE

Industrial CO2 extraction

In a first production step, the plants are decarboxylated by heating to 100-150 ° C and crushed. CBDA is converted to CBD. Thereafter, cooled, liquid carbon dioxide is compressed by a pump to 50-70 bar and fed into the so-called extractor , in which the plant material is located. In a further production step, the extracted ingredients are separated in a so-called separator from the remaining substances by means of pressure and temperature.

This method is gentle on the plant and flower material, and further important pharmacological substances such as terpenes remain undamaged. In addition, carbon dioxide is cost-effective, environmentally friendly, occurs in nature and leaves no residues that it transforms after heating again in the gaseous state and volatilizes. This process is used by leading companies such as Endoca to obtain CBD.
Although there are several ways to extract CBD, the purpose is always the same: to extract the cannabinoid in concentrated form so that it is suitable for human consumption.

For CBD products that are legally offered for sale in Germany , this process must always be performed in industrial hemp plants to ensure that the resulting product complies with the maximum THC content laws.

CBD can be extracted in four different ways:

1. THE OLIVE OIL PRODUCTION

Olive oil production is a common process that is most commonly used when people are trying to gain CBD at home. In this method, the vegetable raw material must first be decarboxylated. That is, it must be heated to a certain temperature for a period of time to activate all of the plant’s chemicals.

In general, in the case of hemp, the optimum temperature is 120 ° C for 60 minutes or 140 ° C for 30 minutes. So compounds like CBD can be fully activated. The plant material is then added to the olive oil and heated to 100 ° C for 1-2 hours. This allows the cannabinoids from the plant material to be extracted into the oil and produces a finished CBD oil.

Advantages of the olive oil method:

 

1. She is very safe – she can even be done at home.
2. It is cheap – its low equipment makes this a very cheap process.

Disadvantages of the olive oil method:

 

1. The resulting oil is perishable, meaning it needs to be stored in a dark, cool place as soon as possible.
2. There are only a few returns produced, so it would not be cost-effective for companies to use this method because it involves a lot of work.

2. THE DRY ICE EXTRACTION

 

This method can also be done at home. It takes a little more time and it is a bit more complex.
If you want to try this method, you will need thick, heat-resistant gloves and goggles. Make sure you stay healthy throughout the procedure.
The first step in this method is to cut the hemp into small pieces and place it in a large bucket. Then the plant is covered with about 1.3 kg of dry ice and allowed to stand for 3 minutes. Through this part of the process, the plant resins freeze. Next, the bucket is covered with a mesh bag so that the ice and plant mixture can be mixed by shaking to dissolve the frozen trichomes and resin from the rest of the plant.
Finally, the bucket is turned over and placed on a piece of Plexiglas or a mirror. The frozen resin will fall through the net. Typically, mesh bags of varying thickness are used to squeeze smaller and larger pieces of resin out of the mix.

Advantages of the dry ice method:

 

• It’s a pretty simple method, so anyone can use it.
• There is very little chaos.
• Compared to olive oil production, the yield is relatively high.

Disadvantages of the dry ice method:

 

• The quality of the product can be reduced by shaking too long.
• Dry ice can be quite expensive and hard to come by.

3. THE SOLVENT EXTRACTION

Solvents such as ethanol, inferior alcohol and butane may be used in this manufacturing option. While ethanol extracts all cannabinoids and terpenes from the plant to produce a high quality product, it also extracts chlorophyll, which can have unwanted side effects. Although chlorophyll can be filtered out, this reduces the effectiveness of the oil.
Butane, on the other hand, produces a stronger oil, but often contains solvents that are harmful to health.
Regardless of the solvent used, the process is the same. The solvent is added to the plant material, thereby removing the cannabinoids and terpenes (as well as some chlorophyll). Thereafter, the liquid is heated to evaporate the solvent, leaving only the CBD base oil.

Advantages of the solvent method:

 

• You can produce high quality oil if you know what you are doing.
• The process is very straightforward and simple.

Disadvantages of the solvent method:

 

• Solvents like these are extremely flammable, which makes the process quite dangerous.
• The resulting oil may contain chlorophyll or even residual solvents, which may cause the product to be harmful to your health.

4. THE CO2 EXTRACTION

This is by far the most popular commercial method of CBD extraction because it is not only safe, but also produces a very high quality end product. In fact, there are several types of CO2 extraction, including a subcritical and supercritical method, which we will discuss later.
Basically, CO2 extraction involves the use of pressurized carbon dioxide to extract compounds from the plant. At certain temperatures and pressures, CO2 behaves like a solvent that can be used to extract compounds such as CBD from the plant. The difference is that CO2 is much safer.
This technique requires special equipment, which makes it very expensive. The equipment used converts the CO2 into a liquid by lowering the temperature to below -56 ° C and increasing the pressure to over 517 Pascal (Pa).
After the CO2 has been liquefied, the temperature and pressure are increased to the point where the liquid becomes supercritical , meaning that it has some properties of a liquid and some properties of a gas. That is, a container (such as a gas) can be filled while maintaining the density (as with a liquid). The reason for this is that the product is not denatured or damaged during chemical extraction.
The supercritical carbon dioxide is passed through high-quality industrial hemp in an extractor where it triggers out the cannabinoids. The solution is then passed through a separator and divided into several parts; the supercritical CO2 is re-condensed to a liquid that can be reused.
In the sub-critical CO2 extraction at a low temperature and low pressure are used. It is less likely that terpenes will be damaged, so the aroma is better preserved. However, this form takes longer than its supercritical counterpart. In addition, a lower yield is achieved. There is also the possibility of a medium-critical CO2 extraction , which represents the golden mean of both possibilities.

Advantages of CO2 extraction:

 

• CO2 is safe for consumption, so that the resulting products are not contaminated.
• The method is very effective and brings a high yield,
• The technique allows the production of a pure quality product without the risk of contamination by, for example, chlorophyll.

Disadvantages of CO2 extraction:

 

• This method is expensive due to the required special equipment.
• It also requires some technical skills and should not be done by amateurs.

CO2 extraction equipment

To complete the extraction process, a closed extraction system is required. This ensures that the CO2 never comes into contact with external elements, which is why the system is safe.

The fact that this plant is so high-tech means, of course, that the process can not be done by anyone. In fact, it is stated that a CO2 extraction kit costs around 33,000 euros. The expensive equipment and labor costs of a specialized team drive up the prices of oils produced by this method.

Extracting CBD oil

If you really want to try CBD extraction at home (which we do not recommend, as it is generally better to buy it from a safe, reputable source), there are some very simple techniques available. For example, dry ice and olive oil production are two very simple ways to extract CBD from hemp.
The most common method, however, is CO2 extraction. This is because it is a safe and effective method of producing the best CBD oils. Although it is an expensive and specialized technique, it is certainly unique when it comes to winning CBD with the latest technology.
If you want to buy the best CBD oil, you should make sure that the seller has used CO2 extraction in the manufacturing process.