Closed-loop extraction is not new or unique to the cannabis industry. For many years people have used closed-loop extraction to extract essential oils for things like food additives and perfumes. Recently, however, it has become a widely popular cannabis extraction method. Cannabis industry professionals use closed-loop extraction to extract cannabinoids (THC, CBD) and terpenes from cannabis plant material into an isolated concentrate.

Closed-loop extraction is a form of hydrocarbon extraction. However, unlike other variations of hydrocarbon extraction, closed-loop extraction occurs entirely within a closed system, which keeps the solvent from making any contact with the outside atmosphere. Closed-loop extraction offers benefits that other extraction methods are unable to provide, such as safety and efficiency. 

What is Closed-Loop Extraction?

Closed-loop extraction uses solvents to extract cannabinoids. In the closed-loop system, solvent moves from a containment tank into an area where it can wash over the cannabis plant material. The closed-loop system recycles the solvent, so it washes over the cannabis many times repeatedly. This washing dissolves the cannabinoids and terpenes from the cannabis plant material. The concentrate is then refined, purged of the solvent, and collected.

The most common solvents to use in closed-loop extraction include the hydrocarbons butane, propane, and ethanol. Industry professionals also use carbon dioxide during extraction.

Butane

Butane is the most popular solvent in the cannabis industry. It’s a non-polar, flammable, liquified gas. Its low boiling point ( 31.1°F) allows for the cold-boiling of any residual solvent from the concentrate and preserves temperature-sensitive terpenes.

Propane

Extractors also use propane. Propane is also a non-polar, flammable, liquified gas. ‘Propane’s low boiling point (-43.6°F) is excellent for preserving temperature-sensitive terpenes. Propane can be purged easily and makes a slightly different extraction than butane.

Butane/Propane Blend

However, because propane is much more expensive than butane, it’s common to find closed-loop extraction equipment that works on a blend of butane and propane. Blending butane with propane creates a gas mixture that strips additional terpenes and purges more efficiently than butane alone.

Ethanol and Carbon Dioxide

There are other types of solvents used in extraction, like ethanol and carbon dioxide, and they have their advantages. Ethanol extraction is considered the most efficient at capturing cannabinoids. 

The Key Benefits of Closed-Loop Extraction

The key closed-loop extraction benefits include safety, efficiency, cost-effectiveness, and higher quality products.

Safety

One key closed-loop extraction benefit is safety.  Cannabis industry professionals regard closed-loop extraction as the safest way to extract cannabinoids. 

Hydrocarbon solvents are flammable, pressurized gases. In closed-loop extraction systems, there are no opportunities for leaks if the equipment is maintained and operated at the appropriate standards. A contained system makes the risk of hazard almost non-existent. In fact, in our several thousand installations, we have never had a client have a safety issue or accident with Precision equipment.

Efficiency

Another closed-loop extraction benefit includes a higher-pressure capacity than open-loop extraction equipment. High pressure allows for maximum extraction of cannabinoids.

In addition to controlling temperature, closed-loop extraction systems are excellent at regulating temperature. Temperature directly controls the solubility of cannabinoids, so it’s essential to be able to control the temperature in the system.

Closed-loop extraction systems also prevent the solvent from being evaporated into the atmosphere and allow the solvent to be used many times without needing to be recharged.

Cost-effectiveness

One huge closed-loop extraction benefit is that hydrocarbon solvent is unable to leak out into the atmosphere. Equipment operators can reuse the solvent for extraction after extraction. This benefit leads to savings on solvent purchasing costs for businesses.

Higher-quality product

Closed-loop extraction technologies provide exceptional control over pressure and temperature, which offer an opportunity to produce the strongest, purest cannabis concentrates available. The vacuum oven removes most or all of the solvent’s residue, so many consumers also regard closed-loop extraction products as the safest to consume.

How Precision Extraction Can Help 

Closed-loop extraction is a method of extracting cannabinoids from cannabis plant material that occurs in an entirely closed system. Closed-loop extraction benefits include safety, efficiency, cost-effectiveness, and a higher-quality product.

Industry professionals choose Precision Extraction because of the closed-loop extraction benefits offered by their top quality extraction systems, not to mention the service and support Precision Extraction provides accompanying their equipment. Click here to find out more about closed-loop extraction systems by Precision Extraction.