How molecular distillation works

Molecular distillation is a distillation method that operates under high vacuum. At this time, the mean free path of vapor molecules is greater than the distance between the evaporation surface and the condensation surface, so that the difference in evaporation rate of each component in the feed liquid can be used to improve the liquid mixture. Separation.
How molecular distillation works
Molecular distillation is a special liquid-liquid separation technology. It is different from traditional distillation which relies on the separation principle of boiling point difference, but relies on the difference in the mean free path of the molecular motion of different substances to achieve separation.
When the liquid mixture flows along the heating plate and is heated, the light and heavy molecules will escape from the liquid surface and enter the gas phase. Because the light and heavy molecules have different free paths, the molecules of different substances move different distances after escaping from the liquid surface. If a condensing plate can be properly set up, light molecules reach the condensing plate and be condensed and discharged, while heavy molecules cannot reach the condensing plate and are discharged along the mixed liquid. In this way, the purpose of material separation is achieved.
The pressure difference between the boiling film and the condensing surface is the driving force for the steam flow direction, and a small pressure drop will cause the steam to flow. Operation under 1mbar requires a very short distance between the boiling surface and the condensing surface. A still made based on this principle is called a short-path still.
Short path distiller is a process of thermal separation technology that works at a pressure of 1~0.001mbar. Its lower boiling temperature is very suitable for heat-sensitive and high-boiling substances. Its basic composition: a cylindrical cylinder with a heating jacket, a rotor and a built-in condenser; a film wiper and an anti-splash device are installed on the fixed frame of the rotor. The built-in condenser is located in the center of the evaporator, and the rotor rotates between the cylindrical barrel and the condenser.
The short-path distiller consists of an externally heated vertical cylinder, its central condenser and a film wiper rotating between the distiller and the condenser. Molecular distillation