Measurements and Theoretical Modeling of Isobaric Vapor–Liquid Equilibria and Dynamic Viscosity for the Dibutyl Ether and Butan-1-ol Binary Mixture

Given the high relevance of oxygenated fuel additives, this work provides new and consistent measurements on the low-pressure isobaric vapor-liquid equilibria (VLE) and the dynamic viscosity under room conditions of the dibutyl ether and butan-1-ol binary mixture and their modeling within the entire range of composition by applying the SAFT-VR Mie EoS coupled with the A-Scaling Theory. Experimentally, VLE is attained in a Gillespie-type cell under 50.00, 75.00, and 94.00 kPa, while a Stabinger viscometer is used to quantify the viscosity at 298.15 K and 101.3 kPa. The consistency of the VLE data is carried out using isobaric Herrington and point-point Fredenslund tests. From the reported VLE data, azeotropic behavior with a positive deviation from Raoult’s law is observed under all explored isobaric conditions, and it obeys Wrewski’s law. Despite some overestimation of the azeotropic temperatures, the SAFT-VR Mie EoS can reproduce the VLE. The A-Scaling Theory using SAFT-VR Mie EoS predicts the dynamic viscosity of the mixture after modeling the same property for each pure fluid using available experimental data. The transport property is well described qualitatively, while an extended SAFT-based description is provided as an early direct application to biofuels characterization.