How To Extract Plant Essential Oils Using An Ultrasonic Extractor?

1.Raw material pretreatment
Clean plant materials, remove impurities. Dry materials at under 45℃ to moisture 5%–15%. Crush raw materials to 20–60 mesh for full solvent contact.

2. Solvent preparation & material feeding
Common solvents: petroleum ether, n-hexane, food-grade ethanol. Solid-solvent ratio ranges from 1:15 to 1:30. Put plants and solvent into sealed extraction containers.

3. Ultrasonic parameter setup & extraction
Adopt 20kHz frequency. Control temperature at 25–45 ℃ with circulating cooling water to avoid essential oil deterioration. Run ultrasound for 15–40 minutes; pulse ultrasonic mode is preferred to reduce heat accumulation.

4. Residue separation
Separate plant residues via centrifugation (3000–5000 rpm) or vacuum filtration to obtain clear mixed liquid.

5. Solvent removal and purification
Recycle solvent with rotary evaporator under low temperature (≤40 ℃) and vacuum. Dry residual water with anhydrous sodium sulfate. Freeze and filter citrus oils to remove wax.

6. Storage
Store finished essential oils in brown sealed bottles under cool and dark conditions to prevent oxidation.