Essential Oil (Solvent Extraction)

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About: Hi, I am an amature artist and photographer with a passion for science, technology, the environment and human physiology

If you are anything like me, you would most definitely adore the fresh, stark fragrance of thyme or the sobering whiffs of sage and an easy, cost effective way of capturing these fragrances is to extract them yourself.This instructable is designed to demonstrate and instruct on the solvent extraction of essential oils and fragrances from plant matter. the products of this extraction can be used in perfumes, cooking, and even aromatherapy.

Step 1: Materials and Apparatus

  • An organic solvent (e.g food grade ethanol, if consumption is intended) I used Acetone
  • A whole lot of Plant matter(e.g peppers,cinnamon, rosemary, sage, basil, thyme,etc.)
  • Beaker/ Mason jar
  • Coffee grinder or blender
  • Filter paper
  • Paper towels
  • Baking sheet
  • Hot plate
  • Fan
  • Mesh strainer

Step 2: Leaf Dehydration

  • Thoroughly wash the freshly picked herbs, removing dirt and debris.
  • Spread leaves on paper towel to allow to dry completely.
  • Place the leaves onto a baking sheet and place into the oven or a dehydrator at 180°F/82.2°C.

NOTE: High temperatures can cause oils to aerosolize, hence diminishing yields.

  • leave thee leaves for about 2-4 hours or until they are completely dehydrated (can crumble easily).

Step 3: Leafe Disnitegration

During this step, we take the leaves and chop them up into a powder or flakes. This step optimises the process as it increases the surface area of the leaves and hence exposing more plant matter with the oils to the solvent. The solvent can now easily dissolve more oils.

  • Place the leaves into a coffee grinder or blender and pulse until the desired particulate size is achieved.
  • Empty fragmented leaves in to the extraction vessel.

Step 4: Solvent Extraction

For this step i used a 1:2 ratio of plant matter to solvent

  • Place the allotted amount of solvent into the extraction vessel.
  • Stir or shake continuously for anywhere up to an hour.
  • To optimize this extraction, the suspension can be left for extensive periods of time, in addition to introducing to a low heat (below the boiling point of the solvent). This allow more oils to dissolve into the solvent.

Within the leaves and other plant matter, there are oils and other aromatic substances that give the extract its distinctive scent. the solvent's purpose is therefore to extract the desired compounds by dissolving them into solution.

Step 5: Filtration

During this step, we will attempt to achieve the lowest visual particulate count for the solution.

Filtration and decanting would result in cleaner oil samples.

  • Decant the suspension into a mesh strainer, removing heavy fragments.
  • Pour the filtrate into a coffee filter.
  • Repeat these steps if necessary.
  • Wash leaf matter and filter paper in a little solvent.

NOTE: to remove the chlorophyll from the solution, the solution can be placed under a bright light or in the sun in a caped container to prevent excess solvent loss.

Step 6: Evaporation

NOTE: THIS STEP SHOULD BE DONE IN A WELL VENTILATED AREA AS THE INHALATION OF VOLATILE ORGANIC COMPOUNDS ARE KNOWN TO CAUSE HEALTH COMPLICATIONS.

  1. Place the filtrate onto a hot plate. a water bath can be used if the vessel is not heat competent.
  2. Set the hot plate to the appropriate temperature which facilitates the boiling of the solvent, stir continuously.
  3. Placing a fan to blow across the surface of the solution will decrease the time needed for complete evaporation.
  4. Stop the evaporation process when the solution begins to thicken and/or when the pungent scent of the solvent is minimal.
  5. Step 1-4 is completely optional and dependent on the amount of solvent used.

What occurs during this step is, the solution of our extract and solvent is being separated. the solvent evaporates, leaving behind oils and other compounds.

Step 7: Bottling & Storage

  • The essential oils/extracts should be stored in a dark, air-tight bottle and in a cool place, as heat, light and air are known to degrade the quality of the oil/extract.

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    8 Discussions

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    ziont2DIY Hacks and How Tos

    Reply 4 months ago

    Hi, thanks for the feedback. Much appreciated as it is my first instructable.

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    belseyziont2

    Reply 3 months ago

    Excellent job, especially if it's your first instructable!

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    bcihlar

    4 months ago

    hmmm? 1/2 oz shake or buds use coconut oil instead & medical butter...much sager ways 2 extract oils etc than using chemical 2 break down....better 2 let sit in 90 proof ever clear mason jar then just strain w/cheese clothes & get pure oil...just you tube medical cannabis edibles

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    Cat00x

    4 months ago

    I’m also a little confused about solvents. Would you please explain what they are, what types are available, where to get them, etc? I have seen thyme oil used in healing but am not sure what a food grade solvent is. Thanks in advance for your answer.

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    ziont2Cat00x

    Reply 4 months ago

    Hi, we use solvents because we want to dissolve the oil and other aromatic compounds. I say "food grade" because someone had concerns with it being edible. Some solvents have consumption deterrents that induce nausea and a bitter taste; hence, getting food grade solvent would avoid that contamination and negative effects.

    So a solvent is a liquid that dissolves a solute. In this case the solvent could be ethanol, methanol, hexane, acetone,isopropanol, mentholated spirits etc. and the solute would be the oils and aromatic substances. You can get near pure acetone, and methanol at your local hardware or pharmacy. Ethanol can be obtained through vodka or a chem store. ethanol in high concentrations are generally harder to source.

    NOTE: if you're planning on using the oil medically, you should know that medical thymol has just thymol as its main ingredient. The extract we made in this instructable has other compounds such as chlorophyll, waxes, etc.which came from the leaf.

    To get your near pure thymol i would recommend steam extraction and not solvent extraction.

    Thank you for your comment and let me know if there is anything that i can help with or should change in the instructable.

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    Ninzerbean

    Question 4 months ago

    So am I to understand that there are oils hiding in the herbs? The solvent gets the oils to be oils? Then what? What would one do with say thyme oil that was made with something I would not feel safe in drinking. You say that the solvents can be used in all sorts of ways - but how exactly and why? Thank you for writing this up, I just don't understand.

    1 more answer
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    ziont2Ninzerbean

    Answer 4 months ago

    In most aromatic substances, such as spices and so on, the usual cause of its scent is the presence of an oil and other aromatic substances,like an essential oil. We use solvents to extract the oils from the plant while dissolving it. I used thyme just as an example. I don't necessarily recommend drinking but if its unavoidable, try using ethanol (the alcohol present in beverages) as your solvent and use a low heat and a fan to get off as much residual ethanol as possible.

    Thanks for the comment, let me know if i can explain it a little better.