Densities (p) and sound velocities (u) of the pure liquids obtained from different biomass conversion: furfural, furfuryl alcohol, toluene, and ethanol were measured at temperature range from 283.15 K to 31335 K at 10 K interval using a vibrating tube densimeter and sound velocity analyzer (Anton Paar DSA 5000M). Besides that, the densities and sound velocities of the binary systems {furfural or furfuryl alcohol (1) + toluene (2)) and {furfuryl alcohol (1) + ethanol (2)) in the above mentioned conditions and over the entire range of composition were also measured. From these physicochemical data, thermodynamic excess functions, such as excess molar volumes, V-m(E), isentropic compressibility, kappa(s), and deviation in isentropic compressibility, Delta kappa(s), were calculated and correlated using the Redlich Kister polynomial equation. The sign and magnitude of these quantities have been interpreted in term of molecular interactions between components of molecules. (C) 2015 Elsevier B.V. All rights reserved.