Closed-Loop Extractors: The Basics

Closed-Loop Extractors: The Basics

Posted by USA Lab Equipment on Oct 14th 2020

There are many different ways to extract a substance from another material in order to yield a pure extract. One of the most prominent extraction methods used in many laboratories today is closed-loop extraction. While open-loop extraction was previously the leading extraction method, processes have since evolved to create the safer, more economical, and highly efficient process of closed-loop extraction. To learn about the basics of closed-loop extractors, including what they are, how they work, and what their many benefits are, continue reading this comprehensive guide.

What Is Closed-Loop Extraction?

Closed-loop extraction refers to an advanced extraction method that allows technicians to extract a substance from another material without exposing any solvents to the open air during the process. Instead, the solvents are contained within the closed-loop system, which seals them off from the air as the extraction process takes place. The ability to seal off the solvents from air yields numerous benefits that impacts the safety, quality, cost, and efficiency of the process and resulting product.

Applications of Closed-Loop Extraction

For decades, lab technicians have used closed-loop extractors to separate valuable substances from other materials. Below, we have listed some of the most common applications of the closed-loop extraction process.

  • The extraction of CBD from the hemp plant
  • The extraction of essential oils
  • The extraction of food additives
  • The extraction of scents used to produce perfume
  • The extraction of dyes and other materials for beauty products
  • The extraction of food additives

Basic Components of Closed-Loop Extractors

Closed-loop extractors are highly advanced systems that consist of numerous different parts. Some of the key components of closed-loop extraction systems include:

  • Solvent tank: In a closed-loop extractor, the solvent tank is responsible for containing the desired solvent that you wish to use in your extraction process.
  • Vacuum pump: A pump designed to help the solvent move more easily throughout the closed-loop system. The vacuum pump can also help recover a solvent when used to pull a vacuum on an empty recovery tank.
  • Material column: Contains the material from which you want to extract a substance.
  • Collection basin/chamber: Used to house the solvent-oil mixture during the evaporation process. It will also store the pure extract after the solvent has evaporated, and the extraction process is complete.
  • Blasting chamber: The area where a pressurized pump sprays the solvent onto the material from which the extract is being separated.
  • Recovery pump: Used to depressurize the chamber inside the vacuum oven.

How Does Closed Loop Extraction Work?

Closed-loop extraction begins by placing the desired material from which a substance will be extracted into the material column and placing the solvent into the solvent tank. The solvent will then fill the material column. Once the solvent and the material have made contact, oils will begin to dissolve into the solvent to eventually create a solvent-oil mixture.

The solvent-oil mixture will then make its way into the collection base where its components will be separated to create a pure extract. To do so, the solvent will be evaporated from the mixture by placing the collection base in warm water and the solvent tank in dry ice or ice water. Doing so will create a temperature differential that causes the solvent to evaporate and move from the collection basin to the solvent tank. Because the solvent never comes in contact with the outside air during the closed-loop process, it can be collected and stored for future use in the system.

Once the vaporized solvent has re-entered the solvent tank, it will condense back into a low-pressure liquid. After the solvent has been evaporated and transported back into the solvent tank, a pure extract will remain in the collection basin.

The Benefits of Closed-Loop Extraction

In comparison to other extraction processes, such as open-loop extraction, closed-loop extraction offers numerous advantages that contribute to its widespread popularity. 


One of the most notable benefits of closed-loop extraction is the safety of the process. Closed-loop extraction is currently one of the safest extraction methods in practice. Because closed-loop systems seal off the air, the potential for any gasses from flammable solvents to escape during the process is almost completely eliminated. As a result, the risk of explosions which can occur due to flammable gas leaks in the system is also effectively reduced to a negligible amount. Thus, opting for closed-loop extraction over other processes, such as open-loop extraction, can greatly increase the safety of laboratory personnel. 

Cost Savings

In addition to improving safety, the ability of closed-loop extractors to contain chemical solvents also helps laboratories save resources throughout the extraction process. By containing the chemical solvents used in the extraction process rather than allowing them to escape, they can then be reused for future extractions. As a result, laboratories can save money by not having to purchase as many chemical solvents as they would for a process that isn’t as tightly sealed.


Another key benefit of closed-loop extraction is the efficiency of the process. Because closed-loop systems are fully contained, they prevent any pressure buildup in the system from being lost. As such, the closed-loop extraction process facilitates a greater amount of pressure at a consistent rate, which helps improve the efficiency of the process. 

Product Quality

Closed-loop extraction also offers the added benefit of yielding a higher-quality product. Unlike other extraction processes, closed-loop extraction doesn’t leave a solvent residue. As a result, it produces purer concentrates that can be used to create higher-quality products. Plus, the increased temperature control and pressure balance that results from the sealed system generally yields a more potent, flavorful product, which further attests to its higher quality.

USA Lab Equipment is a leading provider of top-quality laboratory equipment. Our extensive array of innovative laboratory equipment includes a variety of solvents as well as specialized extraction equipment to facilitate efficient closed-loop extraction processes. In addition, we also offer laboratory essentials such as laboratory chest freezers, glassware, filtration equipment, stands, and clamps. To learn more about our stock of over 1,000 different new and used, competitively priced laboratory equipment items, contact us today.

Closed-Loop Extractors: The Basics