Volumetric Properties of Short-Chain Chloroalkanes

Abstract

To study the influence of molecular structure on the volumetric properties of chloroalkanes, the densities of 1-chloropropane, 2-chloropropane, 1-chlorobutane, 2-chlorobutane, 1-chloro-2-methylpropane, and 2-chloro-2-methylpropane have been measured using a high-pressure high-temperature vibrating tube densimeter system over a temperature range from (283.15 to 328.15) K and a pressure range from (0.1 to 65.0) MPa. In the case of 1-chloropropane, 2-chloropropane, and 2-chloro-2-methylpropane the temperature ranges were (283.15 to 318.15) K, (283.15 to 308.15) K, and (283.15 to 323.15) K, respectively. The experimental densities have been satisfactorily correlated with temperature and pressure using the Tait equation. Moreover, using this equation and thermodynamic relations, isobaric expansibility, isothermal compressibility, and internal pressure have been calculated and analyzed in terms of molecular interactions and structure. The analyzed chloroalkanes follow the regular behavior of the liquids, and dipole−dipole interactions are stronger in primary than in secondary or tertiary chlorinated compounds, as it could be expected. ■ INTRODUCTIONThe reliable knowledge of the volumetric behavior of pure compounds and their mixtures is of great importance in many fields of research as well as in industrial practice. The densities of fluids as a function of temperature, pressure, and composition are particularly important for the design of industrial plants, pipelines, and pumps. Furthermore, reliable density values are the basis for the development of correlation equations and equations of state. 1−4 Chloroalkanes are compounds of great interest due to their use in industry mainly as degreasing agents, detergents, paint removers, solvents, and chemical intermediates; 5,6 moreover, from a theoretical point of view, the study of density and derived properties provides valuable information about the strength of dipole−dipole interactions and free-volume effects. In this study we report densities of 1-chloropropane, 2-chloropropane, 1-chlorobutane, 2-chlorobutane, 1-chloro-2-methylpropane, and 2-chloro-2-methylpropane in a temperature range from (283.15 to 328.15) K (in the case of 1-chloropropane, 2-chloropropane, and 2-chloro-2-methylpropane the temperature ranges were (283.15 to 318.15) K, (283.15 to 308.15) K, and (283.15 to 323.15) K, respectively) and in a pressure range from (0.1 to 65.0) MPa.Different approaches are used in the literature for the correlation of compressed liquid densities; from equations of state 7 to explicit density-equations. 8 In this work we have employed the well-known Tait equation 9 to correlate our experimental results with temperature and pressure. Using the fitting equation and thermodynamic relations some related properties, such as isobaric expansibility, isothermal compressibility, and internal pressure, have been obtained.A survey of the literature shows that ρT and pρT studies involving the chloroalkanes considered here are scarce 6,10−15 and most of them are mainly focused on 1-...

Speed of Sound and Density of 1-Chloropropane in the Range of Temperatures 180–373 K and Pressures up to 196.1 MPa

“…To compare these data with the ones available in literature, we choose corresponding isotherms and interpolated our experimental data by six-order polynomials (AAD < 0.01%) to the pressure values given in the reference sources. The resulting average absolute deviations are, respectively, 0.40% for the isotherms T = 313.15 K up to the pressure value P = 65 MPa from ref., and 0.059% and 0.057% for the isotherms T = 313.15K and T = 333.15K, each of which is represented by the pressures P = 0.274 MPa and P = 4.994 MPa, from ref .…”

“…2,3 At the same time, available experimental thermodynamic data for this substance are extremely used by the temperature range around the room temperature for the both atmospheric pressure (and the saturation 4−9 line) and the single phase region limited in addition by relatively low pressures. 10,8 For this reason, the principal goal of this work is to provide a set of measurements of the volumetric properties, the isobaric heat capacity, and the speed of sound in 1-chloropropane for the sufficiently wider region of temperatures from around 20−30 K above up to the melting point at atmospheric pressure, and the density and the speed of sound for larger temperatures up to around 60 K above the boiling point at saturation conditions as well as the density and the speed of sound under high pressure from the ambient temperature to the maximal temperature 373.15 K mentioned above. In addition, we will discuss the possibility, which provides the fluctuation theory-based Tait-like equation of state (FT-EoS) for predicting the density under high pressures in the points, which were not covered by the direct measurements.…”

“…Halogenated normal alkanes are widely applied to various industrial applications; in particular, 1-choropropane is used for synthesis of ionic liquids and reactions with their participation. , At the same time, available experimental thermodynamic data for this substance are extremely used by the temperature range around the room temperature for the both atmospheric pressure (and the saturation − line) and the single phase region limited in addition by relatively low pressures. , …”

“…Figure 1. Comparison of the measured values of the density ρ (dots supplied with error bars) fitted by the cubic polynomial with coefficients given in Table2(solid line) and the literature-based data: squares, 4 diamonds, 5 circles, 6 pentagons,7 and asterisks 8. Inset: the measured and fitted values of the speed of sound c (dots and line as above) and the literature-based data shown as pentagons, 7 up-directed triangles,14 and down-directed triangle 15.…”

Volumetric Study of the Binary Mixtures Containing a Branched Hexane and an Isomeric Chlorobutane

“…The rest of the parameters can be obtained using Flory's theory [12,13]. Physical properties of the pure compounds [14,15] together with calculated Flory's parameters are given in Table 3, the number of contact sites per segment of a molecule, s, has been calculated using the method proposed by Bondi [16].…”