Vaporization from Binary Mixture Surface under Vacuum

Abstract

The rates of evaporation of binary solutions, DBP(dibutyl phthalate)-EHP(di-2-ethyl-hexyl phthalate) and EHP-EHS(di-2-ethylhexyl sebacate), and the compositions of distillate were measured, using a pot still with stirrer under the vacuum. Then the following results were obtained.
1) The observed relative rates of evaporation were found to be smaller than the theoretical ones obtained from the rate of evaporation of pure liquids.
2) The relative rate of evaporation increases with increase of rotating speed, but decreases with increase of rates of evaporation.
3) The results mentioned above can be well explained by a simultaneous heat and mass transfer model, in which both convection and diffusion are considered in the liquid film.