Fractional Distillation Cannabis

With cannabis products, especially cannabis extracts and concentrates, taking the cannabis industry by storm, it really boils down to the final product your company sells and creates. As a rule of thumb, the better the equipment you use, the purer the product is, with little to no extra effort included in its creation. When creating extracts, they need to undergo distillation and fractional distillation cannabis is by far the most commonly used than other distillation methods as it creates a far purer product. Let’s have a look at the process together.

Source: shutterstock.com / Photo Contributor: Kanjana Kawfang

What Is Fractional Distillation Cannabis?

The process of distillation takes place after the cannabis material has undergone winterization and decarboxylation. During winterization, the fatty acids found in cannabis are removed from the extract, which then undergoes decarboxylation, i.e., it activates the desired compounds. Once winterization and decarboxylation are complete, it’s time for the distillation process. There’s fractional and simple distillation, but here, we’ll only focus on fractional distillation cannabis.

Fractional distillation, often referred to as short-path distillation or molecular distillation, is used to separate and further purify the cannabinoids in the later stages of creating a cannabis oil extract. Typically, THC and CBD have different heating and boiling points when isolating them in the process. If you want, let’s say, to take only CBD from the extract, the short-path distillation cannabinoids temperature would be quite different when isolating THC. 

In simple terms, by altering the temperature and pressure within the distillation system, it becomes possible to separate different compounds, like cannabinoids and terpenes, based on their boiling points, while resulting in the highest possible purity and doesn’t degrade the cannabinoids.

Moreover, fractional distillation has the ability to isolate but also remove certain compounds found in the extract in order to further purify it. 

The fractional distillation process

To obtain purified cannabis compounds the process usually begins with extracting cannabinoids and terpenes from the plant material using solvents like CO2 and ethanol. This crude oil extract is then subjected to further purification through fractional distillation.

In fractional distillation, the crude extract is boiled to create vapor. During the process, a boiling flask heats the crude oil, and the compounds are separated in the oil by using controlled temperatures so the cannabinoids don’t degrade. The flask is heated, making the cannabinoids and terpenes vaporize. Then, the vaporized compounds are cooled off to liquid.

The difference between fractional and simple distillation is that fractional distillation is a more precise method that involves the use of a fractionating column to separate liquids with closer boiling points.

Why is fractional distillation better? Fractional distillation leads to a better separation of compounds than simple distillation. When it comes to high-concentration oils, fractional distillation is the best option since it separates terpenes, residual solvents, and trace compounds.

Equipment and setup of the fractional distillation process

The following are the equipment pieces needed to perform fractional distillation of cannabis compounds.

Distillation flask

The process starts with the distillation flask, which is usually made of glass and has a round bottom shape. This is the vessel where the crude oil or mixture is placed for heating. 

Heating mantle

A heating mantle is an electrical device wrapped around the distillation flask. The role of the heating mantle is to provide heat for vaporization. The mantle regulates the temperature during the distillation process. Once the flask is heated, the mixture begins to evaporate.

Condenser

The condenser is a glass or metal tube connected to the distillation flask. It allows the vaporized compounds to cool and condense back into liquid form.

Source: shutterstock.com / Photo Contributor: Quality Stock Arts

Fractional column

This is the key component of the equipment. It is a long tube with trays and packing materials. The fractional column has a large surface area for the vapor to condense and re-evaporate. The separation happens because compounds with different boiling points condense and vaporize at different heights in the column. 

Vacuum pump

Fractional distillation is sometimes done under vacuum conditions to lower the boiling points of the compounds and reduce thermal degradation. So, the vacuum pump helps the separation process and makes it more efficient.

Collection vessels 

Each distinct component collects in its respective collection vessel, allowing for the isolation and collection of different compounds. A slight temperature variation can affect the separation efficiency of the final product. That is why temperature control is important in preventing thermal degradation. 

The resulting extract is then put into a distillation flask. The flask is heated, making the cannabinoids and terpenes vaporize. The vapor goes through the fractional column. 

Advantages and Challenges 

We have sorted the following as advantages of fractional distillation.

• Higher purity – fractional distillation allows the separation of compounds based on their boiling points, leading to higher-purity extracts.

• Versatility and consistency – this process can be used to extract many cannabis compounds, like cannabinoids and terpenes, each with its own unique properties. This means that fractional distillation enables the production of customized cannabis formulations.

Moreover, this process provides a precise and controlled method for separating cannabis compounds. This consistency ensures that the resulting products have consistent quality and potency.

Yet, there are challenges in achieving high purity and consistency with fractional distillation. Some of the challenges are:

• Contaminants – impurities and contaminants present in the cannabis crude extract may disrupt the distillation process, affecting the purity of the final product.

• Degradation – some compounds, like cannabinoids, may break under high temperatures, influencing the extract composition.

Factors Influencing Fractional Distillation

Several factors influence the fractional distillation of cannabis. These include:

• Temperature gradients – a well-controlled temperature gradient is crucial for the process of fractional distillation to be a success. Keeping a perfect temperature consistency, you’ll let the compounds vaporize at their respective boiling points, and further purify the extract. 

• Vacuum pressure – vacuum pressure is applied to lower the boiling points of compounds during distillation. By reducing the pressure inside the system, the boiling points of the compounds decrease, allowing for more controlled separation. Vacuum pressure improves the efficiency of the distillation process.

• Starting material and excretion methods – the starting material used, like the quality of the cannabis plant, impacts significantly on the distillation. The cannabinoid and terpene profiles, moisture, and impurities are all factors that influence the distillation process.

Source: shutterstock.com / Photo Contributor: SD_FlowerPower

Conclusion

Fractional distillation cannabis is a technique used to separate and purify the different compounds in cannabis extracts. Temperature, pressure, and fractional columns are all factors that are very important in the process.

Fractional distillation has its benefits, like higher purity, consistency, and versatility. Yet, it also has a few challenges, like contaminants and degradation.

Factors influencing fractional distillation include temperature gradients, vacuum pressure, and starting material and extraction methods.