Wiped Film Distillation Operation - Post 2

Wiped Film Distillation Operation - Post 2

Dialing in the distillation

Running a robust distillation starts with understanding your feed material and your goals. It is important to understand the components of your feed and have a goal for the first pass. For instance, if you know your material contains 30% solvent, your goal for pass one should be to remove that solvent.

Once you know what your mixture contains, then it is time to select parameters. If your first target is a solvent, you should select a pressure where the solvent boils readily. For instance, if the vapor pressure of the pure solvent at 25°C is 80 Torr, then 80 Torr would be a good choice for the vacuum level of the still.

Simply choose a condenser temperature of about 15°C, or use cold water. This will provide enough cooling to condense the solvent vapors into distillate.

Then, perform the actions from post 1 of this series. Set the vacuum to 80 Torr. Warm the jacket to about 100°C. Start the flow into the system. Turn up the wipers to about 300 RPM. And there you have it - you are distilling.

Once the distillate and residue streams seem equilibrated, it is time to check the distillation. If you have gear pumps and can pump out of the system, the distillation can be checked by weighing the streams. Take a cup and collect 1 minute of distillate. Weigh the amount collected. Repeat with the residue stream. Use the weights to determine the percent distillate being collected. Compare that number to the goal and adjust heat as needed.

The startup process is really very simple. If there are more questions about this, please check out my website for all the posts I have written about wiped film distillation: https://lnkd.in/gjQHSzPr

Photo is courtesy of Pope Scientific, Inc.