Speed of Sound and Derivative Properties of Ethyl Laurate from Rayleigh–Brillouin Light-Scattering Spectroscopy

Abstract

The experimental speeds of sound combined with Brillouin frequency shifts of ethyl laurate at temperatures from 294.97 to 572.89 K along six isobaric lines from 0.1 to 10.0 MPa were measured by Rayleigh–Brillouin light-scattering spectroscopy. The expanded relative uncertainty in the reported speeds of sound in ethyl laurate is estimated to be 1.3% (coverage factor k = 2 with a confidence level of 0.95). Within the temperature limits of 303.15–383.15 K and at pressures up to 10.0 MPa, the derived thermoacoustic properties of ethyl laurate including density, specific isobaric heat capacity, isentropic compressibility, isobaric thermal expansivity, isothermal compressibility, the difference in isobaric and isochoric heat capacity, internal pressure, and intermolecular free length were studied. Because of the heavily updated data of density and the speed of sound in the literature, a modified Jacobson’s model for biodiesels was proposed over the temperature range from 293.15 to 343.15 K, which is able to calculate the intermolecular free length of ethyl laurate with higher accuracy compared with Jacobson’s model.

Thermodynamic Properties of 1-Butanol + Ethyl Laurate Binary Mixtures by Combining Experimental Speeds of Sound with Volume Translated Peng–Robinson Equation of State

“…The superscripts cal and exp stand for calculated value and experimental value of fluid, respectively. This work employs the fluid density data, the sound of speed data of 1-butanol, ,, and the sound of speed data of ethyl laurate from the literature to fit the volume translation parameter. Then, the experimental data of the mixture are utilized to fit the binary interaction parameter k ij .…”

“…The detailed equipment information used in the system, as demonstrated in Figure S4 has been introduced in our earlier papers. 39,45,53 In the Supporting Information, Figure S5 shows the schematics of the temperature and pressure control system.…”

“…The Brillouin frequency shift can be accurately measured by using a Fabry–Perot interferometer (FPI) that has a FSR of 1.5 GHz. The detailed equipment information used in the system, as demonstrated in Figure S4 has been introduced in our earlier papers. ,, In the Supporting Information, Figure S5 shows the schematics of the temperature and pressure control system.…”

“…The previous literature reports on the speed of sound for 1-butanol or ethyl laurate are listed in Table . The investigated temperatures of the above studies are generally in the low-temperature region (while the temperature during the engine injection process can reach as high as 600 K , ), and no scholars have investigated the 1-butanol + ethyl laurate binary system.…”