Sebastiano Tomassetti , Giovanni Di Nicola , Fabio Polonara , Matteo Moglie , Giulio Santori
{"title":"Liquid-liquid equilibria of biodiesel + glycerol and biodiesel + water binary systems","authors":"Sebastiano Tomassetti , Giovanni Di Nicola , Fabio Polonara , Matteo Moglie , Giulio Santori","doi":"10.1016/j.fluid.2025.114431","DOIUrl":null,"url":null,"abstract":"<div><div>The liquid-liquid equilibria (LLE) of the biodiesel + glycerol and biodiesel + water binary systems are experimentally measured at atmospheric pressure and in the temperature range from 310.35 K to 338.15 K, conditions relevant to the industrial process, solving the experimental challenges related to their direct measurement. The LLE data of these binary systems are pivotal for designing the biodiesel purification processes and determine the chemical equilibrium constant of the transesterification reaction of vegetable oil into biodiesel. However, unlike to the present study, this information is typically indirectly extrapolated from models regressed on ternary systems, undermining the reliability of the results. The experimental data were compared against the calculations provided by the UNIQUAC and UNIFAC models, with the binary interactions parameters (BIPs) of the UNIQUAC model validated on the experimental data. To ensure a thermodynamically consistent representation of the phase behaviour and smooth the experimental scattering of trace components, the BIPs are regressed by means of an algorithm that considers the experimental uncertainty. The results are compared with LLE data for biodiesel + glycerol and biodiesel + water from ternary systems measured by other laboratories.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"595 ","pages":"Article 114431"},"PeriodicalIF":2.8000,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Fluid Phase Equilibria","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0378381225001013","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The liquid-liquid equilibria (LLE) of the biodiesel + glycerol and biodiesel + water binary systems are experimentally measured at atmospheric pressure and in the temperature range from 310.35 K to 338.15 K, conditions relevant to the industrial process, solving the experimental challenges related to their direct measurement. The LLE data of these binary systems are pivotal for designing the biodiesel purification processes and determine the chemical equilibrium constant of the transesterification reaction of vegetable oil into biodiesel. However, unlike to the present study, this information is typically indirectly extrapolated from models regressed on ternary systems, undermining the reliability of the results. The experimental data were compared against the calculations provided by the UNIQUAC and UNIFAC models, with the binary interactions parameters (BIPs) of the UNIQUAC model validated on the experimental data. To ensure a thermodynamically consistent representation of the phase behaviour and smooth the experimental scattering of trace components, the BIPs are regressed by means of an algorithm that considers the experimental uncertainty. The results are compared with LLE data for biodiesel + glycerol and biodiesel + water from ternary systems measured by other laboratories.
期刊介绍:
Fluid Phase Equilibria publishes high-quality papers dealing with experimental, theoretical, and applied research related to equilibrium and transport properties of fluids, solids, and interfaces. Subjects of interest include physical/phase and chemical equilibria; equilibrium and nonequilibrium thermophysical properties; fundamental thermodynamic relations; and stability. The systems central to the journal include pure substances and mixtures of organic and inorganic materials, including polymers, biochemicals, and surfactants with sufficient characterization of composition and purity for the results to be reproduced. Alloys are of interest only when thermodynamic studies are included, purely material studies will not be considered. In all cases, authors are expected to provide physical or chemical interpretations of the results.
Experimental research can include measurements under all conditions of temperature, pressure, and composition, including critical and supercritical. Measurements are to be associated with systems and conditions of fundamental or applied interest, and may not be only a collection of routine data, such as physical property or solubility measurements at limited pressures and temperatures close to ambient, or surfactant studies focussed strictly on micellisation or micelle structure. Papers reporting common data must be accompanied by new physical insights and/or contemporary or new theory or techniques.