Experimental Measurements and Modeling of Vapor-Liquid Equilibrium of Isobutane and Ethyl Mercaptan Binary System


  • Esther Neyrolles Mines ParisTech PSL University, Fontainebleau, France
  • Alain Valtz Mines ParisTech PSL University, Fontainebleau, France
  • Eric Boonaert Mines ParisTech PSL University, Fontainebleau, France
  • Christophe Coquelet Mines ParisTech PSL University, Fontainebleau, France




Isobutane, Oil and gases, Ethyl mercaptan, Equation of state, Vapor-liquid equilibrium


In this work, new isothermal experimental data of vapor-liquid equilibrium of the isobutane and ethyl mercaptan binary system are presented. The pressure and temperature conditions are up to 1 MPa and between 298 and 343K. The experimental apparatus is based on a “static-analytic method” specially developed for low-pressure measurements. Two online capillary samplers are used to take vapor and liquid samples that are analyzed with a gas chromatograph. The classical Peng Robinson Equation of State is used to correlate the experimental data. The van Ness test is used to check the consistency of the data. The measured data are also compared to predicted values from two predictive models, and a good agreement is found between the PSRK UNIFAC and the PPR78 models and the experimental measurements.


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How to Cite

Neyrolles E, Valtz A, Boonaert E, Coquelet C. Experimental Measurements and Modeling of Vapor-Liquid Equilibrium of Isobutane and Ethyl Mercaptan Binary System. Int. J. Petrol. Technol. [Internet]. 2021Sep.3 [cited 2021Sep.16];8:43-54. Available from: https://www.avantipublishers.com/jms/index.php/ijpt/article/view/993