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Steam Distillation

Steam distillation allows you to distill the free base of E or Chili at the temperature of steam 100 degrees C.
If you were to attempt to distill  at  the boiling point of these substances it would take a considerably higher temperature.
depending upon  which  free base you would be up in the range of 250 degrees .
This methods is equal or superior to the use of a separatory funnel to clean up the reaction mixture, it is much simpler and if done properly can be more effective. The use of steam increases the purity in most cases and involves many less steps, in addition NO non-polar solvent is ever needed, this is a blessing in that a source of contamination is eliminated totally.
The reason this works is that the steam carries these substances across with respect to their vapor pressure.
Here is a simple and effective unit

The product comes across to the collector in the form of a clear free base oil floating on top of distilled water, if HCl is added and the pH adjusted to 7.0, the HCl salt is produced and the solution may be evaporated to give the solid product.
Additional information is provided by placebo
A link to the hive concerning steam distilling

Here are some details for chili,
After the reaction is completed, you may desire to filter out the RP although this is not necessary, either way the post reaction mixture is treated with NaOH, bringing the pH up over 12.5.
This is then placed in the steaming flask and the pressure cooker is turned on, the steam is allowed to bubble through the alkaline reaction mixture carrying Chili free base and steam to the cooling condenser,  condensed into a liquid and drips into the collector vessel.
To make the process more efficient the steaming flask is warmed up in the above example a warming tray is used.
It is important that the steam is still very hot when reaching the steaming flask, so keep the distance between the source of the steam and the flask short, and well insulated.
Use a large steaming flask and don't fill it past 1/2 way to prevent the  alkaline solution from splashing up and contaminating the steam in the condenser.
You may have seen the term splash-head on the hive. A splash-head is designed to prevent this from occurring.

You can use a separatory funnel before steaming to remove the NaOH water and wash the free base, although this entire process is  avoided if you use steam , that is why the steam was initially introduced.

An advanced form of this device would use the following modifications, these are designed to give a consistent temper steam and a hotter steam and to maintain the temperature of the steam constant until it leaves the steaming flask.
First the steam is re-heated by a gas flame before it enters the steam flask
Second the Steam flask is enclosed and surrounded by steam to maintain it at the proper temperature.
These two modifications will give a more pure free base and will allow less water into the condenser , as well as make the process much faster.

If you have access to equipment specific glassware is available to streamline your designs, or the last picture is of a metal super steamer available commercially at a lab supply.

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