Vapor−Liquid Equilibria and Saturated Liquid Densities in Binary Mixtures of Nitrogen, Methane, and Ethane and Their Correlation Using the VTPR and PSRK GCEOS

Abstract

New experimental data are presented for the vapor−liquid equilibria in the binary systems nitrogen + methane, nitrogen + ethane, and methane + ethane including data for the saturated liquid densities covering a temperature range of 130 K to 270 K and pressures up to 10.1 MPa. On the basis of the new experimental data for these binary mixtures, which may be regarded as model mixtures, the performance of the widely used group contribution equations of state VTPR and PSRK was investigated. These studies focused on the equations' ability to represent accurately saturated liquid densities over a wide range of temperatures and pressures when a constant volume translation was applied.

Reference Quality Vapor–Liquid Equilibrium Data for the Binary Systems Methane + Ethane, + Propane, + Butane, and + 2-Methylpropane, at Temperatures from (203 to 273) K and Pressures to 9 MPa

“…(a) Measured and predicted (curves) bubble-pressures for methane (1) + ethane (2) as a function of the measured liquid mole fraction of methane, x 1 : green +, Gupta et al T = 270 K; red ○, Wei et al T = 270 K; blue □, Raabe et al T = 270 K; green △, Janisch et al T = 270 K; ⧫, Davalos et al T = 250 K; red ●, Wei et al T = 250 K. (b) Deviations of the measured methane liquid mole fractions, x 1 , in panel (a) from the corresponding calculated methane liquid mole fraction, x 1,calc , of the default HYSYS PR EOS as a function of x 1 .…”

“…Deviations of measured CH 4 liquid mole fractions ( x 1 ) from the values calculated with the default HYSYS PR EOS ( x 1,calc ) for CH 4 (1) + C 2 H 6 (2) as a function x 1 : red ◊, Wichterle 190 < T /K < 200; blue ×, Wichterle and Kobayashi, , 130 < T /K < 213; green ○, Wilson T = 111 K; +, Davalos et al T = 250 K; purple □, Miller et al 160 < T /K < 180; brown △, Gupta et al 260 < T /K < 280; orange ∗, Wei et al 210 < T /K < 270; red block cross, Raabe et al . 240 < T /K < 270; ▽, Janisch et al 140 < T /K < 270.…”

Density Measurements of (0.99 Methane + 0.01 Butane) and (0.98 Methane + 0.02 Isopentane) over the Temperature Range from (100 to 160) K at Pressures up to 10.8 MPa

“…Such measurements of binary mixtures, in particular in the homogeneous liquid and the supercritical region, at low temperatures and over a wide pressure range are unique thus far. To the best of our knowledge, measurements like reported here have not been carried out elsewhere before as already discussed in our earlier work [5,[9][10][11][12]; other authors only measured data for saturated-liquid densities of binary mixtures and LNG-like mixtures [13][14][15][16][17][18][19][20][21] but not in the homogeneous liquid region below the cricondenbar pressure. For the presented two mixtures, however, no measurements of saturated-liquid densities could be found in literature.…”

Semi-empirical correlation for binary interaction parameters of the Peng–Robinson equation of state with the van der Waals mixing rules for the prediction of high-pressure vapor–liquid equilibrium

“…Data for hydrocarbon systems and related compounds were obtained from a variety of literature sources [8–51] . The first column in Table 1 enumerates the systems considered.…”