Making Essential Oils with the Alembic Pot Still
The Alembic Pot Still is the perfect set up to distil essential oils.
ESSENTIAL OILS DISTILLATION
- Attach the copper condenser arm to the copper dome by removing the nut and O-ring from the base of the condenser. Sit the condenser on the dome and screw the nut and O-ring back into the condenser (check the lid isn’t spinning anymore) to firmly attach the dome to the condenser.
- Insert the thermometer probe into the hole at the top of the column.
- Attach the tubing for the water cooling of the condenser. The thin tube is for the outlet water and connects near the top of the condenser arm and takes the water back to the sink. The thicker tube connects to the water inlet near the tip of the condenser arm, with the other end connecting to the tap.
- Briefly turn on the cooling water supply to ensure there are no leaks in the system. Check again that the water goes in at the end where the spirit comes out and that the water comes out closest to the top of the lyne arm (the end near the thermometer probe).
Plant material can be distilled in water or ethanol (alcohol) solution. Plant will release essential oils that will be carried by the water or the ethanol vapours into the distillate. If using water, essential oils will float at the surface of the hydrosol. If using ethanol, essential oil will be mixed in and the pure oil can not be collected, you will get a concentrated essential oils solution instead.
You will need:
- Clean plant material, and enough water to cover them. Each plant material will require different volumes of water, as an indication, for 1 kg (2.2 lb) of rosemary leaves, add 15 L (4 US Gal) of water. If using ethanol solution, use a 40% ABV solution max.
- 5 L (1.3 US Gal) glass carbuoy
- 6 x 500 ml (17 US fl oz) containers for collecting fractions
- Cooling water supply and a sink
Collect the distillate in fractions (eg 500 ml (17 fl oz) lots or smaller) so you can monitor quality of the output throughout. The quality will drop of at the end and may become more ‘cooked’. Stop collecting when the quality drops. Collect a maximum distillate of 80% of the volume put in the boiler to make sure it does not boil dry and cook the plant material. If using water, the distillate collected will be mainly hydrosol (water based plant extract) but there will be essential oil with it. The oil will separate out over time and will float on the surface (for nearly all oils, there are a few which are denser than water and will end up on the bottom).
The oil can then be separated off from the hydrosol by pipette. We recommend to leave the distillate settling into a narrow container, as the layer of oil will be thicker. The hydrosol can also often be used (rose water, lavender water etc). Yields of oil are low, a yield of 1-2% is considered good. If using ethanol, you won’t be able to separate the oil from the ethanol, and can use the distillate as is comes out.