Molecular distillation is an efficient liquid-liquid separation method, which is to separate substances though the difference among molecular motion mean free path of different substances. Therefore, the whole working process of molecular distillation is about molecular motion. The working process of molecular distillation is as follow:
1. The molecules diffuse from the liquid body to the evaporation surface: in this step, users should thin the thickness of the liquid layer and enhance the flow of the liquid layer as we can, in order to control the speed of distilling molecules.
2. Free evaporation of molecules on the surface of the liquid layer: in this step, the heating temperature is set according to the heated material’s boiling temperature. In the meanwhile, the evaporating speed will increase with the increase of temperature, and vise versa. Therefore, users should choose a economic and proper temperature.
3. The molecules fly from the evaporation surface to the condensation surface: in this step, the vapor molecules may collide with each other or with air molecules remaining between the two sides. And the number of residual gas molecules is the main factor affecting the direction of flight and the evaporation rate.
4. The molecules condense on the condensation surface: this step is the final step, pointed molecules are extracted out. The molecules are gas-phase, so it is necessary to condense the gas-phase molecules into liquid-phase molecules. In this step, it is essential to choose a economic and proper condenser.