Speed of Sound in (Carbon Dioxide + Propane) and Derived Sound Speed of Pure Carbon Dioxide at Temperatures between (248 and 373) K and at Pressures up to 200 MPa

Abstract

The speed of sound in (carbon dioxide + propane) mixtures, with mole fractions of carbon dioxide between 0.938 and 0.998, has been measured at temperature from (248 to 373) K and at pressure between (8 and 200) MPa. We find that the addition of propane to carbon dioxide is highly effective in catalyzing vibration-translation energy transfer and reduces the sound absorption coefficient sufficiently to permit sensitive measurements of the speed of sound at frequencies in the low-MHz range. In this work, a 2 MHz ultrasonic cell based on the double-

Density, Speed of Sound, Compressibility, and Excess Properties of the Carbon Dioxide + n-Heptadecane Binary Mixture from 10 to 70 MPa

“…There is surprisingly limited data concerning the speed of sound in pure CO 2 . High-pressure data were taken from the works of Lin and Trusler and Rivas et al that consisted in extrapolating to 100% of carbon dioxide measurements performed in different CO 2 -rich binary mixtures formed by addition of a doping agent in high-pressure CO 2 . Unfortunately, the reported data were limited to pressures above 20 MPa in conditions where CO 2 was dense enough.…”

Density, Speed of Sound, Compressibility, and Excess Properties of Carbon Dioxide + n-Dodecane Binary Mixtures from 10 to 70 MPa

“…To complement our data, speed of sound data of the literature for pure carbon dioxide are added in Figure 2. These data were obtained from works of Lin and Trusler 22 and Rivas et al 23 for pressure higher than 20 MPa, with an uncertainty of 0.2%, whereas speed of sound values corresponding to 10 and 20 MPa were estimated by the Span and Wagner equation 13 with an uncertainty given by the authors of 1% in this p,T range. Comparison of Figures 2 and 3 shows an opposite trend with CO 2 mole fraction.…”

“…Density and isothermal compressibility of both components were taken from Tables and . Isentropic compressibility of n -dodecane was obtained from Table , whereas those of pure carbon dioxide were determined from density measurement of Table and from speed of sound data taken from the literature. ,, Finally, the isobaric expansion of both components was obtained by derivation of density data by a numerical method based on a perturbation Monte Carlo technique similar to those introduced for isothermal compressibility. Additional density measurements, not reported here, were performed to extend the temperature range from 293 to 343 K and the number of experimental points used for describing an isobar before derivation.…”

Density, Speed of Sound, Compressibility, and Excess Properties in a Carbon Dioxide + n-Docosane Binary Mixture from 10 to 70 MPa

“…For this purpose, the density of pure CO 2 was also measured, but it was impossible to measure the speed of sound due the high absorption of sound waves by pure CO 2 at the working frequency. Consequently, the speed of sound values were taken from the experimental works carried out by Lin and Trusler and Rivas et al for pressures above 20 MPa and from correlations proposed by Span and Wagner developed to represent the thermodynamic properties of pure carbon dioxide across extended pressure and temperature ranges. The density and speed of sound values as well as compressibilities thus obtained for pure CO 2 at 333.15 and 343.15 K together with their estimated uncertainties are listed in Table S1 in the Supporting Information.…”

“…Speed of sound c of the CO 2 + n -C 22 system as a function of CO 2 mole fraction x CO2 at temperature T = 343.15 K and at various pressures p : 10 MPa (blue circle, closed); 20 MPa (black square, open); 30 MPa (red triangle, closed); 40 MPa (black diamond, open); 50 MPa (green square, closed); 60 MPa (black circle, open); 70 MPa (blue cross) (data of pure CO 2 are from the literature − ).…”