Overview
The Vapour Liquid Equilibrium (VLE) Setup is used to experimentally determine the equilibrium composition of vapour and liquid phases of binary mixtures at specified temperature and pressure conditions. An equilibrium still circulates both vapour and liquid phases until thermodynamic equilibrium is achieved, after which samples are withdrawn for composition analysis. The VLE data obtained is plotted as T-x-y or P-x-y diagrams and compared with thermodynamic models such as Raoult's law, Antoine equation, and activity coefficient models (van Laar, Margules, NRTL). The apparatus is critical for validating thermodynamic models used in distillation column design.
Specifications
| Still type | Othmer or modified equilibrium still |
| Material | borosilicate glass or stainless steel |
| Pressure range | vacuum to 2 bar |
| Temperature | ambient to 150 degrees C |
| Composition analysis | refractometer / GC |
| Thermocouple | precision RTD for vapour and liquid temp |
| Condenser | water cooled reflux type |
| Power supply | 220V AC, 50 Hz |