Densities, Sound Velocities, and Refractive Indexes of Tetralin + n-Hexadecane at (293.15, 303.15, 313.15, 323.15, 333.15, and 343.15) K

Abstract

Mixtures of tetralin (1,2,3,4-tetrahydronaphthalene), an aromatic cyclic molecule, and n-hexadecane present asymmetries in chemical nature, shape, and chain length and are frequently found in kerosene and diesel fractions. Aiming at understanding the impact of these asymmetries on some thermophysical properties, this work presents densities, sound velocities, and refractive indexes for this binary system along with the properties of the pure components at (293.15, 303.15, 313.15, 323.15, 333.15, and 343.15) K over whole composition range and at atmospheric pressure. From these data, molar refractivity and excess volume were obtained. Several sound velocity mixing rules were tested, and the best result was for the Wada mixing rule. Pure component densities and sound velocities were correlated with the Prigogine–Flory–Patterson (PFP) model. The binary interaction parameter for this model was obtained from correlation of excess volumes. This model calculated experimental mixture densities very well and calculated reasonably good mixture sound velocities. A negative and high binary interaction parameter allowed us to describe positive excess volume.

Thermodynamic modeling and experimental speeds of sound, densities, and refractive indexes of (tetralin+n-dodecane)

“…It happens because the effect of temperature on the properties is misled, as already mentioned. We also observed this failure of the PFP model for systems (tetralin (1) + n-hexadecane (2)) [5] and (tetralin (1) + n-decane (2)) [6]. The fitted values for the characteristic parameters and binary interaction parameters are summarized in table 4.…”

“…Density and speed of sound data were used to estimate Prigogine-Flory-Patterson (PFP) model [8,9] parameters, allowing the correlation of pure component and mixture data and aiming at helping future studies involving tetralin mixtures. Following the works of Yu and Tsai [10] and our recent works on tetralin mixtures [5,6], (tetralin + n-dodecane) is expected to presented V E close to zero. Also, we had derived isothermal compressibility, k T , from our data and compared it to the values obtained from high pressure density measurements for pure tetralin [11], pure dodecane [12], and a mixture of tetralin and dodecane [13].…”

“…As performed in our previous papers [5,6], experimental density, speed of sound, and derived data have been correlated by Prigogine-Flory-Patterson (PFP) model [8,9]. According to this model, an equation of state is applicable in reduced form to pure liquids and mixtures:…”

“…In this work, the mixing rules of Rao [18], equation (13); Nomoto [19], equation (14); Wada [20], equation (15); Van Dael [21], equation (16), which was meant to be applied to ideal gas mixtures; simplified ideal isentropic compressibility, equation (17); and collision factor theory [22], equation (18), are studied, along with a modification [5,6] of the latter theory presented in equation (19), where the collision factor of the mixture was considered additive in volume fraction instead of in molar fraction. The expressions presented here were subject to proper rearrangement.…”

“…Our previous research has presented some physical properties of two tetralin mixtures, such as (tetralin (1) + n-hexadecane (2)) [5] and (tetralin (1) + n-decane (2)) [6]. In addition, many equations of state [7] have been developed to predict liquid mixture properties.…”