Acoustic and thermodynamic properties of methanol from 273 to 333 K and at pressures to 280 MPa

Abstract

The speed of sound In liquid methanol has been measured at temperatures from 273 to 333 K and at pressures up to 280 MPa, using a phase comparison pulse-echo technique operating at 2 MHz. The density, the isobarlc thermal expansivity, the Isothermal compressibility, the entropy, the enthalpy, and the specific heat have been evaluated from the measured sound speed following a modified computational method. The derived density data were fitted to a 16-constant equation of state within the accuracy of the measurement. In the region of overlap, the experimental data agree well with those determined by direct measurements.

Thermodynamic properties of mixtures of N-methyl-2-pyrrolidinone and methanol at temperatures between 298.15K and 343.15K and pressures up to 60MPa

“…In figure 6a, the speeds of sound in pure methanol are compared with those of Sun et al [24] as deviations from the equation of state of de Reuck and Craven [25]. The two sets of experimental data and the equation of state agree to with about ±0.2% at p = 0.1 MPa.…”

“…The two sets of experimental data and the equation of state agree to with about ±0.2% at p = 0.1 MPa. At higher pressures, the experimental data fall below the predictions of the equation of state, even though the data of Sun et al [24] where used in its development. The agreement between our results and those of Sun et al is within approximately 0.4%.…”

Study of the Effects of Temperature and Pressure on the Thermodynamic and Acoustic Properties of 2-Methyl-1-butanol at Temperatures from 293K to 318K and Pressures up to 100MPa

“…The dependences of the speed of sound on pressure and temperature were approximated by the equation suggested by Sun et al [22]:…”

Thermophysical and thermodynamic properties of ionic liquids over an extended pressure range: [bmim][NTf2] and [hmim][NTf2]

“…Given an isobar of the density and of C p , it is possible to integrate equations (4) and (6) over pressure [15] thus obtaining the (p, q, T) and (p, C p , T) surfaces within the range of pressure and temperature of the experimental speed of sound data. The numerical integration procedure also allows one to calculate other properties, such as the isentropic compressibility, j S , the isothermal compressibility, j T , isobaric thermal expansivity, a p the isochoric heat capacity C v and the thermal pressure coefficient, c v .…”