Phase equilibriums in hydrocarbon systems. Phase behavior in the methane-propane-n-decane system

A re-entrant resonator for the measurement of phase boundaries: dew points for {0.4026CH4+0.5974C3H8}

“…The results reported by May et al [14], from measurements with a dual-sinker densimeter, and those of May et al [15], with a version of the re-entrant cavity optimised to determine ratio of the gas-to-liquid volume within the two-phase region, are both for (1 À x) > 0.75 and cannot be compared directly with our results. Similarly, the majority of the results obtained by (p, V, T, x) methods [8][9][10][11][12][13] differ considerably from our mole fraction and hence cannot be compared directly with our results. However, linear interpolation of p d (x, T) results reported in [9] to our T(p, x) gave a value that is 0.02 MPa (about 0.5 %) below our result at T = 329.11 K, and lies 0.005 MPa below our result at T = 333.83 K, both well within the uncertainty cited in table 1.…”

“…The p d predicted by NIST14 differ from PR SPECS by between 0.67 and 0.96 % while both SRK estimates lie 0.4 % above at T = 315 K and these differences diverge from PR SPECS and our results to be À2.5 % at T = 337 K that is about a factor of 5 greater than the estimated expanded uncertainty of our measurements. To our knowledge, there are only eight publications [8][9][10][11][12][13][14][15] that report the dew pressure of {(1 À x)CH 4 + xC 3 H 8 } as a function of (1 À x) at temperatures in the range (273 to 363) K and all are shown in figure 7 with those listed in table 1. The results reported by May et al [14], from measurements with a dual-sinker densimeter, and those of May et al [15], with a version of the re-entrant cavity optimised to determine ratio of the gas-to-liquid volume within the two-phase region, are both for (1 À x) > 0.75 and cannot be compared directly with our results.…”

“…The operation of the re-entrant cavity is demonstrated with measurements of the dew pressure for {0.4026CH 4 + 0.5974C 3 H 8 } at temperatures in the range (315 to 340) K. There are eight publications [8][9][10][11][12][13][14][15] that report the phase behaviour of {(1 À x)CH 4 + xC 3 H 8 } at temperatures in the range (273 to 363) K. References [8][9][10][11][12][13] report results obtained from (p, V, T, x) measurements, while [14] reports dew pressures obtained with a dual-sinker densimeter. May et al [15] used a re-entrant cavity modified to optimise the determination of liquid drop-out-volume with a resonance at frequencies of GHz.…”

Predicting the phase equilibria of synthetic petroleum fluids with the PPR78 approach

“…In 1970, Wiese et al 52 measured 61 bubble-point pressures and 61 dew-point pressures on 122 ternary systems containing methane þ propane þ n-decane. Unfortunately, it is not always possible from the article of Wiese et al to know whether the dew-point pressures are upper or lower dew-point pressures.…”

Hyperbaric reservoir fluids: High-pressure phase behavior of asymmetric methane +n-alkane systems

“…The coordinates of the second critical endpoint of different methane + ,-alkane systems determined in this work are listed in Table II [17]; I~ [ 14]; I~ [5]; * points based on wide extrapolations.…”