Thermodynamic properties of binary system eugenol + 4- propylguaiacol in wide ranges of temperature and pressure

Abstract

The negative consequences of the use of fossil fuels, as well as the unsustainability of meeting ever-increasing energy requirements with limited reserves of fossil fuels, have led to the intensification of research in the field of renewable energy sources. Thermo-chemical conversion of biomass results in bio-oil with low energy density due to high oxygen content which can be upgraded by hydrodeoxygenation process (HDO). HDO consists of a number of reactions that can overlap so the process management requires knowledge on the thermodynamic properties of all compounds present in the biomass valorization process. Eugenol is promising biomass-derived platform chemical that, depending on used catalyst and reaction conditions, can be converted into a variety of important products including 4-propylguaiacol. Densities of eugenol and 4-propylguaiacol were measured at temperatures (293.15 – 413.15) K and pressures up to 60 MPa. The obtained results were correlated using the modified Tammann-Tait equation, which enabled the calculation of the valuable derived thermodynamic properties, such as the isothermal compressibility, the isobaric thermal expansivity, the internal pressure and the difference between isobaric and isochoric heat capacity. Densities of the binary mixtures eugenol + 4-propylguaiacol were measured at atmospheric pressure and temperatures (288.15 – 343.15) K to examine the influence of interactions between the studied components on the thermodynamic properties of their mixtures.