Densities and speeds of sound of jatropha curcas biodiesel + (C ₄-C ₅) alkan-1-ol binary mixtures

Densities (ρ _mix) and speeds of sound (u _mix) for binary blends of Jatropha curcas biodiesel (1) + n-butanol or n-pentanol (2) were measured at T = (288.15 to 308.15) K and atmospheric pressure, over the entire composition range, with the help of a density and sound velocity meter (DSA 5000 M, Anton Paar). The density values were used to evaluate the excess molar volumes V _mix ^E. The Redlich-Kister polynomial equation was adopted to compute and correlate the results, and a good agreement has been observed between experimental and calculated values. It has been observed that the ρ and u values of pure components and their binary blends decreased with respect to temperature. Further, results have been analyzed in terms of molecular forces functioning between biodiesel and alcohols.