title: Bioethanol production optimization: a thermodynamic analysis.
abstract: In this work, the phase equilibrium of binary mixtures for bioethanol production by continuous extractive process was studied. The process is composed of four interlinked units: fermentor, centrifuge, cell treatment unit, and flash vessel (ethanol-congener separation unit). A proposal for modeling the vapor-liquid equilibrium in binary mixtures found in the flash vessel has been considered. This approach uses the Predictive Soave-Redlich-Kwong equation of state, with original and modified molecular parameters. The congeners considered were acetic acid, acetaldehyde, furfural, methanol, and 1-pentanol. The results show that the introduction of new molecular parameters r and q in the UNIFAC model gives more accurate predictions for the concentration of the congener in the gas phase for binary and ternary systems.
authors.affiliation: School of Chemical Engineering, State University of Campinas, P.O. Box 6066, 13083-970, Campinas, SP, Brazil.
authors.forename: Víctor H
authors.initials: VH
authors.lastname: Alvarez
authors.forename: Elmer Ccopa
authors.initials: EC
authors.lastname: Rivera
authors.forename: Aline C
authors.initials: AC
authors.lastname: Costa
authors.forename: Rubens Maciel
authors.initials: RM
authors.lastname: Filho
authors.forename: Maria Regina
authors.initials: MR
authors.lastname: Wolf Maciel
authors.forename: Martín
authors.initials: M
authors.lastname: Aznar
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000379:methods*; D003198:Computer Simulation; D000431:Ethanol / Q000378:metabolism*; D008954:Models, Biological; D011786:Quality Control; D013816:Thermodynamics; D015003:Yeasts / Q000378:metabolism*
chemical_list: D000431:Ethanol