vanilla essential oil co2 extraction machine

Advantages of using co-solvents in CO2 extraction process

Why co-solvents are used in CO2 extraction processes

The research of supercritical CO2 extraction process using co-solvent, the equipment required for supercritical fluid extraction with CO2 as a single medium and the process parameters required for research are necessary in supercritical co2 extraction process using co-solvent.

The difference is that the device adds an co-solvent addition system.

When optimizing the co2 extraction process operating parameters, it is necessary to consider the type, addition method, amount and speed of co-solvent addition to the target substance extraction rate (or recovery rate) and selectivity influences.

Does CO2 extraction use solvents?

Unlike some websites claim that CO2 extraction method does not use any solvent other than CO2 fluid.
In fact, when extracting some special materials, we also use some co-solvents to help better extraction and improve the efficiency of CO2 extraction process.
A commonly used co-solvent is ethanol (edible alcohol).
In fact, in the CBD oil CO2 extraction process, alcohol will also be used in large quantities, in the process of dewaxing (winterization ).

Supercritical co2 extraction of rosemary essential oil using an entrainer

Advantages of using co-solvents in CO2 extraction process

Taking the extraction of effective components from andrographis paniculata as an example to illustrate the advantages of supercritical CO2 extraction process using an co-solvent.

Studies have shown that andrographolide and dehydroandrographolide are the effective components in andrographolide, both of which are diterpene lactones.

However, andrographolide and dehydrated andrographolide are unstable under heat and are easily damaged during the traditional alcohol extraction pharmaceutical process.

Simply the most complete
CO2 extraction process you can find

CO2 Extraction Process

From raw material preparation, we offer you the most complete CO2 essential oil extraction process.
At the same time, more than 100 CO2 essential oil extraction methods from the laboratory are also provided for you.


how to extract essential oils

Detailed explanation of CO2 extraction process steps of plant essential oils。

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how to extract cbd

About the co2 extraction machine cannabis.
You can read a lot of articles about cbd oil extraction from the Internet, but I can tell you for sure that they are not comprehensive at all, and even have wrong descriptions.

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cosolvent pump of co2 extraction machine
cosolvent pump of co2 extraction machine

pure CO2 extraction process VS ultrasonic ethanol extraction and cold extraction with ethanol

Supercritical pure CO2 extraction has the lowest yield, only 1/10 of other extraction methods; when using 95% ethanol as an co-solvent, operate according to optimized process conditions (extraction pressure 25MPa, extraction temperature 40 ° C, extraction time At 4h, the amount of co-solvent is 1/2 of the raw material), the rate of extracting andrographolide (8.3%), the content of andrographolide (19.79%), and the content of dehydrated andrographolide (12.27%) are much higher than the traditional extraction method, and the product quality is stable and the drug effect is high, and all the indicators are better than the original solvent method.

Although the ultrasonic ethanol extraction method and cold extraction with ethanol have better extraction results, the amount of solvent treatment is large and the solvent loss is large.

The following table compares the effects of different extraction methods on andrographis paniculata.

Extraction methodExtraction rate /%Andrographolide content /%Dehydrated andrographolide content /%
Cold ethanol6.1515.724.35
Ultrasonic ethanol extraction5.0510.173.43
Effect of different extraction methods on andrographis paniculata
Why CO2 is used in supercritical fluid extraction

Advatages and Disadvantages of using co-solvents in CO2 extraction process

The supercritical CO2 extraction process using co-solvents can broaden the application range of supercritical extraction, especially when the extracted components have little solubility in supercritical solvents or require highly selective extraction.

The SFE process using an co-solvent not only improves the solvent’s ability to extract solutes and reduces the amount of solvent required, but also greatly reduces the required pressure.

However, the disadvantage is that the co-solvent complicates the separation of the solute from the solvent and requires the addition of a special recovery system, such as the use of operation units such as evaporation and rectification.It is far less simple than using a single SCF process. The advantages and disadvantages of the method are determined.


CO2 Extraction Machine Buyer’s Guide

As you can imagine, not all supercritical CO2 extractors are made the same.
For more than 30 years, we have customized many CO2 extraction machines (Tabletop CO2 Extractor) for many companies and university laboratories (1 lb CO2 extractor). Because each customer’s CO2 extraction process requirements are different, there are almost no identical machines.

How many liters of CO2 extraction vessels are needed?

The first factor that determines the size of the CO2 extraction vessel is the daily working hours of the plant, which determines the daily extraction batch. The vessel size of the CO2 extractor depends on the biomass to be processed per day.

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How many separators are needed?

How can I custom my separator when I need more terpenes in my How can I custom my separators when need more terpenes in CBD oil extraction process?
Waxes separation and Light oil separation in 1st separator;
Light oil separation in 2nd separator;
To trap lightest and volatile compounds in 3rd separator.
It is important to choose the right vessel size that will meet your current needs as well as future demand.

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How many pressure is best for your CO2 extraction process requirements?

The choice of CO2 extraction pressure is a changing factor. If the extraction pressure is too high, the useless substances in the plant will be extracted, such as wax and chlorophyll. If the extraction pressure is too low, the extraction time will be increased.

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How can the minimum operating costs be achieved?

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Further Reading: CBD Oil CO2 Extraction Machine

CO2 Extraction Process
CO2 Extraction Process

why and how are co-solvents sometimes used in CO2 extraction processes?

A small amount of a co-solvent increases the ability of supercritical carbon dioxide to dissolve polar compounds.  Neat supercritical CO2 has dissolving properties similar to hexane.  This means that, by itself, carbon dioxide is very good for dissolving relatively non-polar materials.  The addition of just a small quantity of co-solvent enhances the solubilizing power of the supercritical carbon dioxide, making it possible to extract much more polar molecules. Typical co-solvents include: methanol, ethanol, and water.

A liquid co-solvent can be added to CO2 to increase its solvent power on polar molecules.

By adding a polar or medium polar co-solvent (ethanol or light alcohols, esters or ketones) in the right percentage and for a correct and pre-determinated time during extraction, it is possible to fine tune total polarity of the supercritical solvent.

Entraining agents have different properties than supercritical CO2. The critical point (CP) of CO2 is 73.8 bar and 31.5° C; ethanol’s CP is 63 bar and 241° C. A mathematical description requires computational chemistry to show how the entraining agents interact with the CO2. Suffice it to say, CO2 will be in the supercritical phase and the entraining agents will be in the liquid phase. This changes the solvent characteristics of the CO2 and improves extraction yields.