LLE experimental data, thermodynamic modeling and sensitivity analysis in the ethyl biodiesel from macauba pulp oil settling step

• Published in: Bioresource technology 2013-03, Vol.131, p.468-475
• Main Authors: Basso, Rodrigo Corrêa, Silva, César Augusto Sodré da, Sousa, Camila de Oliveira, Meirelles, Antonio José de Almeida, Batista, Eduardo Augusto Caldas
• Format: Article
• Language: English
• Subjects: Biodiesel; Biofuel production; Biofuels - analysis; Biological and medical sciences; Biotechnology; Computer Simulation; Energy; Ethanol; Ethanol - chemistry; Ethyl alcohol; Fundamental and applied biological sciences. Psychology; Glycerols; Industrial applications and implications. Economical aspects; Liquid–liquid equilibrium; Macauba oil; Mathematical models; Models, Chemical; Palm Oil; Plant Oils - chemistry; Sensitivity analysis; Settling; Streams; Themodynamic modeling; Thermodynamics
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2012.12.190

► LLE data of glycerol+ethanol+ethylic biodiesel from macauba oil was determined. ► NRTL and UNIQUAC parameters were estimated; UNIFAC parameters were tested. ► LL thermodynamic flash was performed considering biodiesel settling step. ► Ethanol in excess hamper the biodiesel settling. ► Glycerol and biodiesel in settling process output streams were quantified. The aim of this study was to obtain experimental data related to liquid–liquid equilibrium (LLE) of systems containing glycerol+ethanol+ethyl biodiesel from macauba pulp oil, perform thermodynamic modeling and simulate the settling step of this biodiesel using simulation software. Binary interaction parameters were adjusted for NRTL and UNIQUAC models. The UNIFAC-LLE and UNIFAC-Dortmund models were used to predict the LLE of the systems. A sensitivity analysis was applied to the settling step to describe the composition of the output streams as a function of ethanol in the feed stream. Ethanol had greater affinity for the glycerol-rich phase. The deviations between experimental data and calculated values were 0.44%, 1.07%, 3.52% and 2.82%, respectively, using the NRTL, UNIQUAC, UNIFAC-LLE and UNIFAC-Dortmund models. Excess ethanol in the feed stream causes losses of ethyl ester in the glycerol-rich stream and high concentration of glycerol in the ester-rich stream.