Effect of MgCI2 and CaCI2 on the Bubble Point of Mixed- Solvents (Toluene-Isopropyl Alcohol-H20 System)


Nathaniel P. Dugos(1*), Noel P. Cabigon(2), Yolanda P. Brondial(3)

(1) Department of Chemical Engineering Adamson University, Manila, Philippines
(2) MACCH Management and Consultancy Corp.Manila, Philippines
(3) Department of Chemical Engineering De La Salle University, Manila, Philippines
(*) Corresponding Author


This study investigated the effect of CaCl2 and MgCI2,both alkaline earth metal salts on the boiling points of a mixed-solvent system composed of toluene, isopropyl alcohol and water. The effect of the concentration of the salt on the boiling point of this ternary system was also examined. Results showed that mixed- solvents added with CaCl2 boil at higher temperatures than those with MgCl2even though the latter salt is higher in molal concentration. This proves that MgCI2, which has a smaller ionic radius than CaCl2 is more effective in reducing the molecular affinity to polar and associating solvents (water and isopropyl alcohol) than to the non-polar solvent (toluene). The mixed- solvent system added with MgCl2 registered higher boiling point deviation than those with CaCI2, though both showed positive deviations. Based on the results, either of the two salts can be an effective mass separating agent. However it is shown that MgCl2is better than CaCl2 because the solutions with MgCI2 generally exhibited lower boiling points. Though the difference in temperature deviations of the two salts is statistically not significant, a difference in temperature of one degree is economically significant considering the cost of energy.


bubble point, azeotrope, salt effect, molecular affinity

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  1. Bader, M. S. H. (1999) Thermodynamicsoflons Precipitation in Mixed-Solvent Mixtures, J. of Hazardous Materials B69 319-334.
  2. Nagvekar, M., E Tihminlioglu E and Danner R.P. (1997) Colligative Properties of Polyelectrolyte Solutions, Fluid Phase Equilibria 145 15-41.
  3. Cabigon, N.P. and Dugos N.P. (2003) " Bubble Point of Ternary Mixed-Solvents with Alkali Salts (Toluene- Isopropyl Alcohol- Water - NaCI System)" Journal of Research in Science, Computing and Engineering Vol 2 No.1
  4. Dugos, N.P.and Cabigon N.P.(2002) "Separation of Ternary Mixed Solvents (IPA-Toluene- Water System)", Proc. Chemical Engineering Congress 2002
  5. Elliot, R.J. and Lira C.T. (1999). Introductory Chemical Engineering Thermodynamics, Prentice Hall International Series, NJ USA
  6. lliuta, M. C., Thomsen K. and Rasmussen P. (1999) Extended UNIQUAC Model for Correlation and Prediction of Vapor- Liquid-Solid Equilibria in Aqueous Salt System Containing Non-electrolytes. Part A. Methanol-Water-Salt Systems. Chemical Engineering Science, 55, 2673- 2686.
  7. Laidler, Keith J. and MeiserJ.H. (1999). Physical Chemistry 3rd ed. Houghton Mifflin Company, Boston USA
  8. Meyers Raymond H. and Montgomery D.C. (2002). Response Surface Methodology {Process and Product Optimization Using Designed Experiments) 2nded. John Wiley and Sons, NY USA
  9. Smith, J. M.,Van Ness H.C. and Abbot M.M. (2002). Introduction to Chemical Engineering Thermodynamics,6th ed. McGraw-Hill,Inc., New York

DOI: https://doi.org/10.22146/ajche.50147

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ASEAN Journal of Chemical Engineering  (print ISSN 1655-4418; online ISSN 2655-5409) is published by Chemical Engineering Department, Faculty of Engineering, Universitas Gadjah Mada.