Azeotropic points with relative volatility-prediction and calculation

Azeotropic points with relative volatility-prediction and calculation

Saida FedaliHakim Madani 

Department of Mechanics, Faculty of Technology, Laboratory of Studies of the Industrial Energy Systems (LESEI), University of Batna, Algeria

Corresponding Author Email: 
saida_fedali@yahoo.fr
Page: 
38-42
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DOI: 
https://doi.org/10.18280/mmep.040108
Received: 
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Accepted: 
| | Citation

OPEN ACCESS

Abstract: 

In this study, we predict the locus of azeotropes for binary mixtures by using the relative volatility is presented. A simple method is used in binary mixtures: At first we applied the method which is based on experimental data and then we evaluated by thermodynamic model. The model composed:

• Peng-Robinson equation of state

• Mathias-Copeman alpha function

• Wong-Sandler mixing rules

• NRTL model

1,1-difluoroethane (R152a) + n-butane (R600) , carbon dioxide (R744) + 1,1-difluoroethane (R152a) and 1,1,1,2-Tétrafluoroéthane (R134a) + 1,1-difluoroethane (R152a) are the binary mixtures used in this work. The results confirm that there is a good agreement between the predicted values and the experimental data and the relative error does not exceed 1% for the molar fraction and 0.5% for the pressure. In conclusion, this method is considered able to predict the azeotropic location.

Keywords: 

Equation of State, Mixing Rules, Excess Free Energy, Azeotrope, Relative Volatility.

1. Introduction
2. Methods
3. Results
4. Discussion
5. Conclusion
Acknowledgement
Nomenclature
  References

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