High-Pressure Density Measurements for the Binary System Cyclohexane + n-Hexadecane in the Temperature Range of (318.15 to 413.15) K

Abstract

The densities of binary mixtures of n-hexadecane and cyclohexane at high pressures were measured in the range of (6.895 to 62.053) MPa at six different temperatures varying from (318.15 to 413.15) K and for eight compositions. The measurements were made by a high-pressure Anton Paar DMA 512 P densimeter integrated with the Ruska 2370 mercury Free PVT System. The densimeter was calibrated using analytical grade toluene, cyclohexane, and n-heptane as calibration fluids. The experimental error of density measurements is estimated as 0.5 kg·m-3. The measured densities at 348.15 K agree well with the available literature values at different pressures. The excess volumes, thermal expansion, and isothermal compressibility coefficients were obtained from measured densities. All data were correlated successfully with a modified Peng−Robinson equation of state.

Modeling high-pressure densities at wide temperature range with volume scaling: Cyclohexane+n-hexadecane mixtures

“…High-pressure density for this mixture was presented previously by Tanaka et al [26], at only three temperatures. The recent data [24] allows the study of density and derived properties of this mixture for a wider range of temperatures and compositions.…”

“…The isobaric thermal expansion (α) and the isothermal compressibility (k T ) coefficients, and excess volume (V E ) were derived from experimental [24] densities (ρ). These properties are defined, respectively, in Eq.…”

“…(1) at a given pressure P*, from a given temperature T* to a temperature T. A density value at T* and P* must be known, and here values presented by Amorim et al [24] were used. The final step is to integrate Eq.…”

“…The RMSD between calculated and experimental [24] pure components cyclohexane and n-hexadecane densities are presented in Table 1, obtained after estimation of the model parameters. The regressed parameters are presented in Table 2.…”

Correlation and Prediction of Dense Fluid Transport Coefficients. VIII. Mixtures of Alkyl Benzenes with Other Hydrocarbons

“…In Table 1, the experimental measurements [12][13][14][15], T. Makita, Personal communication (1985), [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] used to compute the aforementioned equations for the parameters a i , b i , and C and the experimental temperature ranges and maximum pressures considered are shown. It should be noted that the maximum pressure shown in the table refers to the point above which deviations started to increase considerably, i.e., the correlation is valid up to the maximum pressure quoted in the table.…”