Phase Behavior and Densities of Propylene + Hexane Binary Mixtures to 585 K and 70 MPa

Abstract

In this study, we report phase behavior data for propylene + hexane mixtures at temperatures of 295 to 468 K and pressures to 5.5 MPa and high-pressure mixture density data at temperatures of 295 to 584 K and pressures to 70 MPa. Both the phase behavior and density data are simultaneously determined using a variable volume, high-pressure view cell that is coupled with a linear variable differential transformer. The phase behavior and mixture density data are modeled with the Soave–Redlich–Kwong (SRK), Peng–Robinson (PR), modified Sanchez–Lacombe (MSL), and perturbed-chain statistical associating fluid theory (PC-SAFT) equations of state (EoS). The PC-SAFT and MSL EoS provide the best fit of the phase behavior data with a nonzero value of 0.028 for k ij . Likewise, the PC-SAFT EoS provides the best fit of the high-pressure mixture density data, though the PC-SAFT equation slightly overpredicts the solution density and the calculated densities are relatively insensitive to changes in k ij from zero to 0.028.

Experimental and modeling investigations of the phase behavior and densities of diesel + nitrogen mixtures

“…The apparatus and techniques used to measure HPHT BP and density measurements for each diesel + N2 mixture are described in detail elsewhere [21][22][23][24] and are only briefly presented here.…”

A Multipore Model for Heterogeneous Catalytic Polymerization: Structure–Performance Relationships

“…Instead of the density data of the propylene/n-heptane system which to the best of our knowledge is not yet available, we calculated the density of the very similar propylene/n-hexane mixture at T = 303.15 K and P = 115 kPa by extrapolation of the data presented by Mallepally et al [43] The calculated value is presented in Table 1.…”

Fluid properties at high pressures and temperatures: Experimental and modelling challenges

“…Currently, many research laboratories use the synthetic technique with a variable-volume, view cell to visually observe and map the pressure, temperature, and composition of phase transitions. The versatility of the view cell apparatus is exemplified by its use for a wide range of applications, including the determination of vapor-liquid equilibria [17,18], the solubility of a polymer in pure and multicomponent solvents [19], the solubility of a solid in a supercritical fluid, the formation of gas hydrates, and the cloud point behavior of ionic liquid-CO2 systems.…”

“…However, there is still only a modest amount of density data for higher alkanes at temperatures greater than 373K (212°F), likely due to the temperature sensitivity of the highly accurate electronic techniques used for these measurements. Similarly, a modest amount of density data exists for simple binary mixtures, such as hexane + propylene, toluene + propylene, and toluene + ethylene [17,18]. The techniques used to measure HPHT density are oftentimes coupled with those used to measure viscosity, and these techniques are briefly mentioned in the next section.…”