Evolution and Testing of a Metallic Ebulliometer for VLE Determination

Document Type : Research Article


Escuela de Ingenierías Industriales y Civiles. Universidad de Las Palmas de Gran Canaria 35017 Las Palmas de Gran Canaria, Canary Islands, SPAIN


An ebulliometer designed with automated feeding was tested and verified in this work. The ebulliometer is made of stainless steel. The feeding of the substances is automatically controlled with a computer. In the equipment, both the liquid and vapor phases are recirculated.  The binary mixtures isobutyl acetate + 1–propanol and isobutyl acetate + 2–propanol were studied and the vapor–liquid equilibrium of these mixtures was determined at 101 kPa. The isobaric T–x–y data are reported, including the azeotropic point of the isobutyl acetate + 1–propanol binary system. The calculations have been carried out considering the non–ideal vapor phase and the activity coefficients of the liquid phase have been obtained. The thermodynamic consistency of the system was verified with the Van Ness point–to–point test. The f–f approach was used to evaluate the data reproducibility by considering the Perturbed Chain–Statistical Associating Fluid Theory (PC–SAFT).


Main Subjects

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