Speed of Sound, Density, and Related Thermophysical Properties of the Methyl Caprate + Methyl Oleate Binary System from 0.1 MPa to 70 MPa at 303.15 K

Measurement and Modeling of Speed of Sound in Binary Mixtures of Methyl Oleate with n-Hexane or n-Decane Under Pressure

“…The results are reported in Tables 2 and 3 for n-C6 + MC18:1 and n-C10 + MC18:1 binary systems respectively. The values measured in pure alkanes were added in these table whereas the speed of sound values of pure methyl oleate obtained from the same batch of chemical products are available in a previous study [27]. No data were already reported for both systems in the open literature.…”

“…For this purpose, additional volumetric measurements were conducted using a vibrating tube density meter to obtain the density values of pure n-hexane and n-decane from the same chemical batch as those investigated. These values were then numerically derived with respect to pressure [38] and temperature [39] to obtain the isothermal compressibility and isobaric thermal expansion. The resulting values for density, isothermal compressibility and isobaric thermal expansivity were entered into Tables S.1 to S.3 in the Supporting Information along with their respective expanded uncertainties.…”

Predicting Speed of Sound in Fatty Acid Alkyl Esters and Biodiesels at High Pressure

“…It can be seen in Table S1 that most of the measurements were performed at atmospheric pressure within a limited temperature range (283–353 K), but some of the data were obtained at high pressure (up to 200 MPa) and others at high temperature (up to 500 K). The high-pressure data come from only three different groups, which worked in the ranges of 0.1–35, 0.1–101, ,, and 0.1–200 MPa, ,,,,, respectively. Most of the data available were acquired at pressures of less than 150 MPa, and so the operating pressure range was limited to 0.1–150 MPa.…”

“…In a recent work, studying mixing properties in a fatty acid methyl ester binary system (MC10:0+MC18:1), it was seen that deviations from ideality are negligible in this type of binary mixture but that, despite this, the speed of sound in fatty acid alkyl ester mixtures cannot be predicted from an ideal thermodynamic relation since it requires knowing several thermodynamic properties (molar volume, isothermal compressibility, isobaric thermal expansion and heat capacity) of pure components in addition to speed of sound. Furthermore, when calculating the ideal speed of sound, the error propagation rule produces a significant combined uncertainty that affects the reliability of the values obtained.…”

“…Consequently, it is necessary to resort to alternative properties to circumvent the problems raised by the absence of simple combination rules for speed of sound and the impossibility of using ideal thermodynamic relations. For that purpose, it was seen that both molar compressibility and the product of speed of sound w and molecular weight M , wM can be used and simple combining rules were proposed to predict these properties in binary mixtures. Study of the same binary system (MC10:0+MC18:1), but considering the product of speed of sound w and molecular weight M raised to the power γ ( wM γ ) instead of wM , shows that wM γ can also be expressed in terms of a linear combination of pure component properties wM γ,i by considering the mole fraction as a weighting factor, as follows: …”