Vapor Liquid Equilibrium Lab TAs Faculty instructor Prof. - PowerPoint PPT Presentation

TH-206 Vapor Liquid Equilibrium Lab TA’s Faculty instructor Prof. H.S.Shankar Mriganka Mondal Yogendra singh M Bhavishya Staff member: Mrs. Annie

Objective of the Experiment  To generate vapor liquid equilibrium data for acetone-benzene binary system. Check thermodynamic consistency of the I. experimental data. Present the thermodynamic characteristics and II. calculate constants of Van Laar equation and Margules equation.

Measurement of concentration  Concentration of the sample mixture is calculated by measuring refractive index using analog Refractometer.  Refractive index is nothing but ratio of velocity of light in vacuum to a certain medium.

Experimental set up RTD for temp measurement Vapor sample collector Liquid sample collector

Steps involved during experiment • Get calibration curve for RI Vs Concentration. • Initially mixture - 420ml Acetone + 80ml Benzene. Measure its RI. • Run the expt. till the equilibrium reaches. • Take liquid and vapor samples for RI calculation. Take some amount of mixture out and add same • amount of Benzene to the mixture. Repeat this . •

Calculations  Modified Rault’s law  Calculation of Van Laar equations  Plot ln γ A , ln γ B (on the same graph) and ln( γ A / γ B ) vs X A (as another graph) and check for thermodynamic consistency.  Calculate back the van Laar coefficients using

Problems and precautions  The improper measurement of temperature by RTD sometimes effects the calibration.  Low efficiency of the dimmerstat (heating element).  Non uniform heating leads to sudden build up of pressure inside the container.  Glasses must be used during the experiment as a necessary precaution.

Thank you