| Some plant material cannot tolerate the heated | | | | in aromatherapy or skin care products. |
| forms of extraction such as steam distillation. High | | | | |
| heat damages these plants and once damaged, their | | | | Super Critical Carbon Dioxide (CO2) Extraction |
| essential oils too are damaged and are no longer able | | | | |
| to be extracted. For these plants, as well as others, | | | | The end result of super critical carbon dioxide (CO2) |
| solvents such as ether, ethanol, methanol, hexane, | | | | extraction - one of the newest extraction |
| alcohol and petroleum are used instead. The problem | | | | technologies - is a super-concentrated, high-quality |
| with using solvents to extract essential oils is that | | | | version of essential oil. This rapid extraction method |
| most of the time, residual solvents or impurities | | | | uses lower temperatures and higher pressure to |
| remain in the end product. Because they're impure, | | | | transform carbon dioxide, a gas, into a liquid. It's an |
| those true to aromatherapy refuse to use them. | | | | inert solvent meaning that it's non-reactive and |
| | | | | therefore cannot form another chemical compound. |
| As mentioned above, there are times when solvent | | | | When the extraction process is complete, the carbon |
| extraction makes sense. This process involves a lot | | | | dioxide is returned back to a gaseous state |
| of chemistry and is somewhat confusing to | | | | therefore, no residual remains. All that is left is pure |
| understand but in general it is as follows. | | | | essential oil. |
| | | | | |
| Plant material is first washed in a bath of | | | | Although this technology produces one of the purest |
| hydrocarbon solvents. This process dissolves the | | | | forms of essential oil, it is not yet widely used. The |
| necessary plant materials including the aromatic | | | | equipment needed for this extraction process is very |
| molecules, waxy matter and pigment and the | | | | expensive, which keeps production costs high. And |
| dissolved matter mixes in with the solvent. The | | | | because production costs are high, so too are the |
| solvent mixture is then filtered and distilled using low | | | | costs of the essential oils that are produced via |
| pressure. After distillation and further processing, | | | | carbon dioxide extraction. |
| either a resin or a concentrated concrete remain. | | | | |
| Additional processing using alcohol helps extract the | | | | Maceration |
| essential oils. | | | | |
| | | | | With this essential oil extraction method, hot oil is |
| This is a very fast and cost-effective method of | | | | used as a way to rip apart cell membranes. The plant |
| essential oil extraction, but there is a downside. With | | | | material is first saturated with hot oil and allowed to |
| solvent extraction, residual solvents remain and their | | | | soak until the cell membranes rupture. As they break |
| presence can cause problems if used by individuals | | | | apart, essential oils are released into the oil in which |
| with allergies or sensitive skin. That's another reason | | | | the plant material is soaking. When the release period |
| why essential oils extracted using solvents are used | | | | is complete, the plant material is removed from the |
| in the manufacturing of perfumes and fragrances, not | | | | oil. The oil that remains then gets decanted. |