Isobaric (vapour + liquid) equilibria for three binary systems (toluene + anisole, n-butylbenzene + anisole, and guaiacol + anisole) at 101.33 kPa

• Isobaric VLE data of three binary systems containing anisole were measured.
• The data were never reported before and are useful for pyrolysis oil separation.
• The VLE data were correlated well by the activity coefficient models.

Bio-oil, derived from biomass flash pyrolysis, has been recognized as an important renewable resource for resolving the current energy crisis. However, the pyrolysis oil consists of complicated composition and has some undesired properties, including acidity, relatively high viscosity, limited thermal stability, low heating value, which hinder the direct application of bio-oil. So, separation and purification of the pyrolysis oil are important and the phase equilibrium data of the bio-fuel related mixtures is essential for the design and simulation of the processes. In this context, isobaric vapor–liquid equilibrium (VLE) data for the three binary mixtures in the pyrolysis oil, toluene + anisole, n-butylbenzene + anisole, and guaiacol + anisole, have been measured at 101.33 kPa by a modified Rose–Williams still. All of the experimental VLE data were checked by the Herington analysis method and were verified the thermodynamic consistency. No azeotropic behavior was observed in the three binary systems. The measured data were well correlated by the non-random two-liquid (NRTL), universal quasi-chemical activity coefficient (UNIQUAC), and Wilson model, respectively. The corresponding parameters for the three models were obtained. The average absolute deviations of the temperature and the vapor compositions correlated by the three models for all the systems are below 0.55 K and 0.019, respectively.