Article pubs.acs.org/jced
Vapor−Liquid Equilibria Measurements for Di‑n‑Propyl Ether and Butyl Ethyl Ether with n‑Heptane Jamie T. Cripwell, Cara E. Schwarz, and Andries J. Burger* Department of Process Engineering, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa S Supporting Information *
ABSTRACT: Isobaric vapor−liquid equilibrium (VLE) data were measured for two binary systems comprising n-heptane with one of di-n-propyl ether (DNPE) or butyl ethyl ether (BEE) at 60 kPa. Slight positive deviations from ideality were apparent in both systems, but not so strong as to result in azeotropic behavior. The data for both systems were shown to be thermodynamically consistent using both the Wisniak L/W and McDermottEllis consistency tests. Data were further well correlated by the nonrandom twoliquid (NRTL) activity coefficient model and fairly predicted using the Dortmund-modified UNIFAC model. The data presented serve to fill the gap in the literature for data sets of structural isomers of C6 ethers with n-heptane, where data for the linear isomers are absent. This data, combined with that available for the branched isomers, serve to highlight the role of polar functional group location on associated mixture behavior in such systems.
1. INTRODUCTION Properties of mixtures containing ethers and hydrocarbons, and in particular the phase behavior of these systems, have garnered much attention in recent years. This has been largely due to industrial interest in these ethers as fuel additives to increase octane ratings and decrease automotive emissions associated with these fuels. Particular attention has been given to mixtures of hydrocarbons with methyl tert-butyl ether (MTBE),1−4 tertamyl methyl ether (TAME),1,5−11 ethyl tert-butyl ether (ETBE),2,12−15 and di-iso-propyl ether (DIPE);16,17 an extensive review of vapor−liquid equilibrium (VLE), liquid− liquid equilibrium (LLE), and excess properties for industrially relevant ethers with nonpolar solvents is also available in the literature.18 This plethora of available data highlights the drive for generating experimental phase equilibrium data for specific industrial applications. In two previous works, a more systematic approach was taken in the generation of new phase equilibrium data for binary systems of hydrocarbons with medium length linear ketones19 and esters.20 There, VLE data for different structural isomers of the polar molecule coupled with the same n-alkane were generated and, in this way, the effect of the polar functional group location on phase behavior of the different isomers could be investigated. The rationale for this theoretical approach is to use the systematically measured phase equilibrium data, previously unavailable in the literature, as a test for the analytical capacity of predictive thermodynamic models. The aim of this work is to extend that analysis to linear ethers. To our knowledge, no data has been measured for the constitutional isomers of medium length (C6 to C9) linear ethers with a common n-alkane. Within the existing literature, © XXXX American Chemical Society
however, there are multiple data sets for the branched C6 ethers (i.e., ETBE,2,13,14,18 TAME,5,6,11,18 and DIPE17,18) with nheptane, but not for their linear chain isomers. This presents an ideal opportunity to systematically expand the body of available data for structural isomers with a common second component, as has been the aim of this series of data papers. Thus, the aim of this work will be to generate isobaric VLE data for two C6 ether structural isomers with n-heptane and to model these systems using correlative and predictive activity coefficient models.
2. MATERIALS AND METHODS 2.1. Apparatus and Procedure. A Pilodist VLE 100 D allglass dynamic recirculating still was used for the generation of the vapor−liquid equilibrium data presented here. The system pressure was measured using a Wika UT-10 pressure transmitter, with an operating range of 0−1.6 bar absolute and an uncertainty of 0.1% of full scale output, namely, 1.6 mbar. The equilibrium temperature was measured with a 4-wire Pt-100 probe connected to a digital Hart Scientific Thermometer, with a calibrated uncertainty of 0.1 K between 313 and 413 K. The calibration was performed by a SANAS (South African National Accreditation System) approved laboratory, adhering to international calibration standards. The unit is the same as that used in our previous works and the reader is directed to the paper dealing with the ester/nalkane systems20 for a detailed account of the experimental procedure. Received: July 5, 2016 Accepted: November 1, 2016
A
DOI: 10.1021/acs.jced.6b00587 J. Chem. Eng. Data XXXX, XXX, XXX−XXX
Journal of Chemical & Engineering Data
Article
The instrumental uncertainty in the pressure transmitter is equivalent to an absolute value of 1.6 mbar. Over and above this value, control of the system pressure by manual throttling induced pressure fluctuations of no more than 0.2 kPa during unit operation. These values are once again additive and result in a maximum absolute uncertainty in the pressure, u(P), of 0.36 kPa. The most significant contribution to compositional uncertainty was found to be drift in the calibrated response factors of the GC over the time the samples were analyzed. This was accounted for by analyzing samples of known composition, using the same calibration curves, after all experimental samples for a given system had been analyzed. These deviations resulted in an average compositional uncertainty of 0.006 mol fraction, with a maximum deviation 0.010 mol fraction. Thus, the reported uncertainty in vapor, u(y), and liquid, u(x), mole fractions reported here is 0.010 mol fraction.
Duplicate analytical samples were prepared from each equilibrium phase using 2-ethyl-1-hexanol as a solvent. The samples were then analyzed by gas chromatography using a Varian CP-3380 gas chromatograph (GC) with flameionization detector. The GC had a ZB Wax capillary column (dimensions 30 m × 0.32 mm × 1 μm) installed and was operated at 523 K using helium as the carrier gas. Quantification of sample compositions was achieved making use of established calibration curves based on peak areas from the GC, using 2-heptanone as an internal standard. 2.2. Materials. The components, internal standard, and analytical solvent were all supplied by Sigma-Aldrich, with manufacturer purities as indicated in Table 1. The n-heptane Table 1. Chemicals Used (Supplied by Sigma-Aldrich) and Manufacturer Purities component
CAS No.
purity (mass fraction)
n-heptane di-n-propyl ether butyl ethyl ether 2-ethyl-1-hexanol 2-heptanone
142-82-5 111-43-3 628-81-9 104-76-7 110-43-0
0.99 ≥0.99 0.99 ≥0.996 0.98
3. THERMODYNAMIC CONSISTENCY Experimental phase equilibrium data need to adhere to the thermodynamic limitations imposed by the Gibbs−Duhem equation. To this end, the experimental data in this work were tested for thermodynamic consistency using both the Wisniak L/W24 and McDermott−Ellis25 consistency tests. The Wisniak L/W test imposes a maximum value of 5 for the value of D for a given system to be considered thermodynamically consistent. Both the DNPE/n-heptane and BEE/nheptane systems adhered to this restriction with D values of 4.28 and 3.15, respectively. The McDermott−Ellis consistency test works on a point-topoint basis, which serves to remove thermodynamically inconsistent data points in a pairwise comparative fashion. Each pair of data points has a calculated maximum deviation, Dmax, which is based on the temperature, pressure, and compositional uncertainties. This maximum should not be exceeded by the D value of the pair, which is a function of the activity coefficients of the system’s components. The D values of all data presented in this work were lower than their respective maximums and thus considered thermodynamically consistent by this test.
and both ethers were analyzed by gas chromatography to ensure that supplier assays were as listed. Results showed that no significant impurities were present and that the component purities met or exceeded the assays listed by the manufacturer. As a result, all components were considered appropriate for experimentation and used without any further treatment. Further support for the component purity is provided by the good agreement between the experimentally measured normal boiling points and their corresponding literature values,21 provided in Table 2. This good agreement extends to a larger Table 2. Comparison between Measured Normal Boiling Points and Accepted Values in the DIPPR 801 Database21 for n-Heptane and the Two Linear C6 Ether Isomersa
a
component
measured
literature
n-heptane di-n-propyl ether butyl ethyl ether
371.28 362.87 365.25
371.58 363.10 365.35
4. EXPERIMENTAL RESULTS The T−x−y data for both the DNPE/n-heptane and BEE/nheptane systems at 60.0 kPa are tabulated in Table 4. Also included are the corresponding experimental activity coefficients, calculated by Aspen Plus. The T−x−y and x−y plots for these systems are presented in Figure 2a,b while calculated activity coefficients and dimensionless excess Gibbs energies are shown in Figure 3a,b. Liquid phase activity coefficients are calculated using the γ−φ approach to describing phase equilibrium, as per eq 1:
Standard uncertainty: u(T) = 0.12 K.
range of the pure component vapor pressures for all three components, as indicated by the comparison in Figure 1a with the experimental values tabulated in Table 3. From the relative deviation plot of Figure 1b, deviations between the experimental vapor pressures and the literature values22,23 are consistently less than 2%, with the majority of the data showing deviations of less than 1%. These highly favorable comparisons support the claim that component purities are acceptable for the experimental work. 2.3. Uncertainty. According to the most recent certificate of calibration, the Pt-100 probe did not exhibit temperature deviations greater than 0.1 K over the temperature ranges of interest to the systems in this study. Further, at the time of sampling, fluctuations in the order of 0.02 K were apparent for the equilibrium temperature. Given the additive nature of these uncertainties, the total uncertainty in temperature measurement, u(T), recorded here is 0.12 K.
xiPisatγi = yP i
φi φisat
⎛ v sat(P − Pisat) ⎞ exp⎜ − i ⎟ RT ⎠ ⎝
(1)
Here, Pisat and visat are the saturated vapor pressure and liquid density of component i, respectively, and φi and φisat are the fugacity coefficients of component i in solution and at saturation, respectively. The ratio of the fugacity coefficients in eq 1 is determined using the second virial coefficients by means of eq 2 B
DOI: 10.1021/acs.jced.6b00587 J. Chem. Eng. Data XXXX, XXX, XXX−XXX
Journal of Chemical & Engineering Data
Article
Figure 1. Comparison between experimental and literature vapor pressures for components used in this work. (a) Direct comparison with literature values, where reference data are represented by means of a correlation through the actual data points for ease of reference. (b) Relative deviation of measured values compared to reference data. Key: n-heptane (◇, double dot-dash line22), DNPE (△, dotted line23) and BEE (○, solid line23).
Table 3. Experimentally Measured Vapor Pressures for nHeptane and the Two Linear C6 Ether Isomersa P/kPa
T/K
n-Heptane 101.30 371.28 88.40 366.87 83.45 364.95 76.47 362.11 70.24 359.38 64.60 356.78 56.20 352.58 50.97 349.68 46.80 347.16 38.89 341.94 30.59 335.45 26.15 331.39 a
P/kPa
T/K
P/kPa
DNPE 101.30 96.32 89.30 84.25 78.97 72.36 62.30 57.75 49.98 42.54 36.71 29.35
given how narrow the phase envelope is for these systems and that the activity coefficients are calculated from the experimental compositions. The Gibbs free energy of the BEE system appears to be larger than that for the DNPE system. This trend supports the arguments for the effect of functional group location on phase behavior as the gE/RT for the more sterically hindered molecule is lower than the isomer whose polar group is more terminally located.
T/K BEE
362.87 361.18 358.73 356.85 354.82 352.11 347.55 345.34 341.15 336.55 332.57 326.73
101.30 96.36 90.59 79.60 71.58 63.63 56.24 51.67 44.96 38.60
365.25 363.47 361.44 357.31 354.01 350.44 346.80 344.21 340.35 336.22
5. THERMODYNAMIC MODELING The experimental data were correlated with the NRTL activity coefficient model and predicted using the Dortmund-modified UNIFAC27 model. Regression of the NRTL interaction parameters was achieved using the built-in regression procedure in Aspen Plus. The value of the nonrandomness parameter (α) was set to a constant value of 0.2 for both systems, as per the recommendation for systems of hydrocarbons with nonassociating compounds.28 The regression procedure in Aspen Plus defines the τij parameter as per eq 3, with the required Aij and Bij parameters determined by minimizing the objective function for the activity coefficients, as defined in eq 4.
Standard uncertainties: u(T) = 0.12 K, u(p) = 0.36 kPa. φi φi
sat
⎡ B (P − P sat) + P(1 − y)2 (2B − B − B ) ⎤ i 12 11 22 ⎥ = exp⎢ ii RT ⎣ ⎦ (2)
τij = Aij +
In this equation, Bii and Bij are the second virial coefficients which are calculated by means of the Tsonopoulos correlation,26 with pure component properties (Pisat, visat, and Bii) calculated using the appropriate DIPPR21 correlations. The difference between the types of intermolecular forces exhibited by the polar ether and nonpolar alkane are highlighted by the positive deviations exhibited by both systems. These deviations are strong enough to produce a constricted phase envelope, but not so strong as to result in azeotropic behavior. The role of the dipolar ether group’s location in the carbon backbone on the mixture behavior is manifested in the pure component boiling points within these systems: for DNPE, the centrally located and sterically hindered oxygen atom produces weaker polar interactions than the more terminally located oxygen in the BEE, resulting in its lower boiling point. Both systems exhibit some scatter in the activity coefficient and excess Gibbs energy data. This can however be attributed to the compositional uncertainty, which will have a large impact
n
OF =
Bij (3)
T n
∑ (γ1exp − γ1calc)i2 + ∑ (γ2exp − γ2calc)i2 1
1
(4)
Regressed NRTL parameters are reported in Table 5, along with the absolute average deviations (AAD) in y and T, as well as the root-mean-square errors (σ) in γ and gE/RT for both the NRTL correlation and the UNIFAC prediction. The NRTL correlations can be seen to fit the equilibrium data of both systems well in Figure 2a,b, highlighted by the low AAD values for both the vapor composition and the temperature. Considering the correlations of the activity coefficients and the excess Gibbs energy in Figure 3a,b, the correlation can be expected to fit the activity coefficient data well, given the nature of the objective function in eq 2. However, the effect of the scatter in the experimental activity coefficients is highlighted in the overshoot of the gE/RT correlations. Nonetheless, root-mean-square errors (σ) in γ and C
DOI: 10.1021/acs.jced.6b00587 J. Chem. Eng. Data XXXX, XXX, XXX−XXX
Journal of Chemical & Engineering Data
Article
Table 4. Experimental VLE Dataa for Temperature T, Liquid Phase Mole Fraction x, and Vapor Phase Mole Fraction y for the DNPE (1)/n-Heptane (2) and BEE (1)/n-Heptane (2) Systems at 60.0 kPa T/K
a
y1
x1
354.63 354.42 354.01 353.65 353.33 352.66 352.55 352.34 352.17 351.94 351.75 351.66 351.25 351.07
0.000 0.038 0.078 0.115 0.144 0.215 0.232 0.266 0.273 0.307 0.325 0.339 0.381 0.386
0.000 0.027 0.055 0.082 0.101 0.154 0.180 0.207 0.209 0.232 0.250 0.256 0.301 0.310
354.63 354.63 354.37 354.22 353.87 353.79 353.41 353.34 352.90 352.71 352.68 352.43 352.32 352.06
0.000 0.000 0.035 0.049 0.095 0.111 0.160 0.166 0.212 0.245 0.248 0.293 0.305 0.344
0.000 0.000 0.026 0.035 0.071 0.082 0.121 0.127 0.169 0.197 0.195 0.236 0.250 0.285
γ1
γ2
T/K
1.109 1.120 1.128 1.151 1.152 1.072 1.071 1.095 1.120 1.105 1.130 1.093 1.080
1.000 0.994 0.995 0.994 0.992 0.988 1.000 0.996 0.995 0.983 0.987 0.977 0.988 0.999
350.92 350.65 350.46 350.29 349.60 349.60 349.23 349.07 348.96 348.71 348.62 348.54 348.35 348.09
1.127 1.157 1.133 1.162 1.144 1.134 1.102 1.102 1.128 1.108 1.093 1.089
1.000 1.000 0.998 0.999 0.998 0.994 0.993 0.995 1.002 0.999 0.993 0.992 0.997 0.996
352.00 351.62 351.59 351.50 351.39 351.29 351.17 351.19 351.05 350.96 350.89 350.77 350.73 350.78
y1
x1
γ1
DNPE (1) + n-Heptane (2) 0.411 0.332 1.082 0.450 0.372 1.066 0.467 0.386 1.073 0.496 0.418 1.057 0.558 0.485 1.048 0.570 0.494 1.050 0.619 0.545 1.046 0.632 0.564 1.037 0.652 0.583 1.039 0.683 0.618 1.035 0.688 0.627 1.032 0.712 0.651 1.031 0.738 0.683 1.024 0.762 0.714 1.020 BEE (1) + n-Heptane (2) 0.348 0.289 1.088 0.395 0.336 1.076 0.400 0.346 1.061 0.413 0.357 1.066 0.436 0.381 1.056 0.459 0.403 1.053 0.466 0.410 1.054 0.479 0.423 1.051 0.504 0.444 1.057 0.511 0.455 1.050 0.525 0.472 1.042 0.528 0.475 1.045 0.543 0.490 1.043 0.546 0.488 1.052
γ2
T/K
y1
x1
γ1
γ2
0.993 0.995 0.993 0.996 1.010 1.002 0.999 1.013 1.004 1.007 1.017 1.006 1.015 1.032
348.09 347.94 347.74 347.60 347.49 347.26 347.11 346.98 346.82 346.72 346.63 346.55
0.765 0.792 0.813 0.837 0.857 0.883 0.911 0.933 0.955 0.979 1.000 1.000
0.715 0.747 0.776 0.804 0.828 0.858 0.892 0.920 0.946 0.974 1.000 1.000
1.022 1.017 1.013 1.011 1.009 1.011 1.007 1.006 1.006 1.004 1.000 1.000
1.023 1.028 1.046 1.047 1.053 1.046 1.065 1.071 1.075 1.069
0.998 1.004 1.011 1.008 1.011 1.010 1.013 1.009 1.002 1.010 1.015 1.019 1.018 1.004
350.51 350.35 350.22 349.98 349.85 349.71 349.55 349.32 349.25 349.12 349.01 348.93 348.89 348.84
0.579 0.615 0.644 0.680 0.716 0.749 0.783 0.811 0.851 0.879 0.927 0.963 0.985 1.000
0.528 0.565 0.603 0.644 0.684 0.721 0.760 0.790 0.835 0.867 0.921 0.960 0.984 1.000
1.041 1.038 1.024 1.021 1.016 1.012 1.010 1.013 1.008 1.008 1.004 1.002 1.001 1.000
1.019 1.018 1.033 1.043 1.049 1.058 1.064 1.072 1.078 1.088 1.103 1.132 1.121
Standard uncertainties: u(T) = 0.12 K, u(p) = 0.36 kPa, and u(x1) = u(y1) = 0.010.
Figure 2. T−x−y (○, vapor and △, liquid) and x−y (⧫) representations of experimental data for (a) DNPE (1)/n-heptane (2) and, (b) BEE (1)/nheptane (2). Included are the corresponding NRTL correlations (gray, long-dashed line) and UNIFAC predictions (red, short-dashed line). Stick model representations of the ethers show the location of the ether functional group.
gE/RT are of the same order of magnitude as our experimental uncertainties and reaffirm a good correlative fit of the data. The UNIFAC model provides an accurate prediction of the DNPE/n-heptane system and agrees well with the NRTL correlation for this system, as typified by the T−x−y and x−y plots in Figure 2a. The prediction for the BEE/n-heptane
system however does not exhibit the same degree of agreement in Figure 2b; the predicted bubble and dew points temperatures appear to be systematically overpredicted in the mixture composition space. The relatively small AAD values in y and T (Table 5) suggest that these deviations are small but the difficulty in accurately modeling this system is emphasized by D
DOI: 10.1021/acs.jced.6b00587 J. Chem. Eng. Data XXXX, XXX, XXX−XXX
Journal of Chemical & Engineering Data
Article
Figure 3. Activity coefficient (○, ln γester; △, ln γn‑octane;) and gE (■, system gE) plots for (a) DNPE (1)/n-heptane (2) and, (b) BEE (1)/n-heptane (2), including corresponding NRTL correlations (gray, long-dashed line) and UNIFAC predictions (red, short-dashed line).
Table 5. NRTL Correlation Parameters, with Average Absolute (AAD) and Root Mean Square (σ)a Deviations for Both NRTL and UNIFAC system
A12
B12 (K)
A21
DNPE/nC7 BEE/nC7
15.201 16.397
−4760.86 −5423.31
−3.587 −7.536
B21 (K)
AAD (y1)
AAD (T)
σ (γ1)
σ (γ2)
σ (gE/RT)
NRTL 869.0 2408.2 UNIFAC
0.000(3) 0.000(1)
0.04 0.02
0.02 0.01
0.02 0.01
0.004 0.004
0.032 0.005
0.29 0.20
0.03 0.03
0.18 0.01
0.033 0.034
DNPE/nC7 BEE/nC7 a
Root mean square deviation: n
σ(F ) =
∑1 (F exp − F calc)2 (n)
where n is the number of data points excluding those for the pure component.
before, the effect of the location of the polar ether functional group within the carbon backbone appears to significantly affect the macroscopic phase behavior of binary mixtures containing a structural isomer with a common second component. The witnessed phase behavior is well correlated by semiempirical activity coefficient models and predicted qualitatively by group contribution methods, although a bias toward one molecular orientation is suggested in the predictions of the latter.
how narrow the phase envelope for this system is. Considering the activity coefficient and gE plots of Figure 3, the UNIFAC model can be seen to underpredict the excess Gibbs energy of the system and exhibit larger root-mean-square errors than the corresponding NRTL correlation. This trend holds for the BEE/n-heptane system, in which the system gE is more notably underpredicted. Combined with the phase equilibrium prediction results, this suggests a bias in the UNIFAC prediction for one molecular orientation of the linear C6 ether over the other investigated here. The data and modeling results presented in this work serve to extend the previous works done on ketone and ester systems. The overall focus of these works has been to investigate the effect of functional group location on the phase behavior of polar structural isomers with a common second component. This data, and that presented in our previous works, will serve to test the capabilities of predictive thermodynamic models in future work.
■
ASSOCIATED CONTENT
S Supporting Information *
The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jced.6b00587. Relative volatility plots for the DNPE/n-heptane and BEE/n-heptane systems at 60.0 kPa (PDF)
■
AUTHOR INFORMATION
Corresponding Author
6. CONCLUSIONS Isobaric VLE data for the binary systems of DNPE/n-heptane and BEE/n-heptane at 60 kPa presented positive deviations from ideality, but not azeotropic behavior. The data served to expand the pool of available data for structural isomers of C6 ethers with a common normal alkane, adding data for linear isomers to the data sets available in the literature for the branched isomers. As with the similar ketone and ester systems
*E-mail:
[email protected]. Tel: +27 21 8084494. Fax: +27 21 8082059. Funding
This work is based on the research supported in part by the National Research Foundation of South Africa (Grant specific unique reference number (UID) 83966) and Sasol Technology (Pty) Ltd. E
DOI: 10.1021/acs.jced.6b00587 J. Chem. Eng. Data XXXX, XXX, XXX−XXX
Journal of Chemical & Engineering Data
Article
Notes
Heptane, and Heptane + Tert-Amyl Methyl Ether. J. Chem. Eng. Data 2011, 56, 2256−2265. (12) Wisniak, J.; Galindo, G.; Reich, R.; Segura, H. Isobaric VaporLiquid Equilibrium in the Systems Ethyl 1,1-Dimethylethyl Ether + 2,2,4-Trimethylpentane and + Octane. Phys. Chem. Liq. 1999, 37, 649−660. (13) Reich, R.; Cartes, M.; Segura, H.; Wisniak, J. Isobaric VaporLiquid Equilibria in the Systems Ethyl 1,1-Dimethyl Ether + Hexane and + Heptane. Phys. Chem. Liq. 2000, 38, 217−232. (14) Villamañań , R. M.; Martín, M. C.; Chamorro, C. R.; Villamañań , M. A.; Segovia, J. J. Thermodynamics of Fuels with a Biosynthetic Component: Vapor−Liquid Equilibrium Data for Binary and Ternary Mixtures Containing Ethyl 1,1-Dimethylethyl Ether, n-Heptane, and Toluene at T = 313.15 K. J. Chem. Eng. Data 2006, 51, 2091−2095. (15) Villamañ ań , R. M.; Vega-Maza, D.; Chamorro, C. R.; Villamañań , M. A.; Segovia, J. J. Thermodynamics of Fuels with a Biosynthetic Component. II. Vapor−Liquid Equilibrium Data for Binary and Ternary Mixtures Containing Ethyl 1,1-Dimethylethyl Ether, 1-Hexene, and Cyclohexane at T = 313.15 K. J. Chem. Eng. Data 2008, 53, 247−251. (16) Fuangfoo, S.; Kersting, M.; Viswanath, D. S. Isothermal VaporLiquid Equilibria for Methyl-1,1-dimethylethyl Ether + 2-Methylpropan-2-ol, Diethyl Ether + Ethyl-1,1-dimethylethyl Ether, 2-Methyl2-butene + (2-Methylbutan-2-ol), and Diisopropyl Ether + Octane. J. Chem. Eng. Data 1999, 44, 405−410. (17) Chamorro, C. R.; Segovia, J. J.; Martín, M. C.; Villamañań , M. A. Isothermal V.L.E. and Excess Molar Gibbs Energy of Binary and Ternary Mixtures Containing Diisopropyl Ether, n-Heptane and Isopropanol at T = 313.15 K. J. Chem. Thermodyn. 2002, 34, 13−28. (18) Marsh, K. N.; Niamskul, P.; Gmehling, J.; Bölts, R. Review of thermophysical property measurements on mixtures containing MTBE, TAME, and other ethers with non-polar solvents. Fluid Phase Equilib. 1999, 156, 207−227. (19) Cripwell, J. T.; Schwarz, C. E.; Burger, A. J. Vapor-Liquid Equilibria Measurements for the Nine n -Alkane/Ketone Pairs Comprising 2-, 3-, and 4-Heptanone with n -Octane, n -Nonane, and n -Decane. J. Chem. Eng. Data 2015, 60, 602−611. (20) Cripwell, J. T.; Schwarz, C. E.; Burger, A. J. Vapor-Liquid Equilibria Measurements for the Five Linear C6 Esters with n-Octane. J. Chem. Eng. Data 2016, 61, 2353−2362. (21) DIPPR 801 Database. Design Institute for Physical Properties Sponsored by AIChE. http://dippr.byu.edu/ (accessed June 2015). (22) Selected values of properties of chemical compounds. Thermodynamics Research Center; Texas A&M University: 1991. (23) Ambrose, D.; Ellender, J. H.; Sprake, C. H. S.; Townsend, R. Thermodynamic Properties of Organic Oxygen Compounds - XLIII. Vapour Pressures of Some Ethers. J. Chem. Thermodyn. 1976, 8, 165− 178. (24) Wisniak, J. A New Test for the Thermodynamic Consistency of Vapor-Liquid Equilibrium. Ind. Eng. Chem. Res. 1993, 32, 1531−1533. (25) McDermott, C.; Ellis, S. R. M. A Multicomponent Consistency Test. Chem. Eng. Sci. 1965, 20, 293−296. (26) Tsonopoulos, C. Second Virial Coefficients of Water Pollutants. AIChE J. 1978, 24, 1112−1115. (27) Gmehling, J.; Li, J.; Schiller, M. A Modified UNIFAC Model. 2. Present Parameter Matrix and Results for Different Thermodynamic Properties. Ind. Eng. Chem. Res. 1993, 32, 178−193. (28) Renon, H.; Prausnitz, J. M. Local Compositions I Thermodynamic Excess Functions for Liquid Mixtures. AIChE J. 1968, 14, 135− 144.
The authors declare no competing financial interest.
■
ACKNOWLEDGMENTS The authors acknowledge that opinions, findings and conclusions or recommendations expressed in any publication generated by the supported research are that of the authors, and that the sponsors accepts no liability whatsoever in this regard. The financial assistance of the National Research Foundation (NRF) towards this research is hereby acknowledged. Opinions expressed and conclusions arrived at, are those of the author and are not necessarily to be attributed to the NRF. Aspen Plus is a registered trademark of Aspen Technology, Inc.
■
REFERENCES
(1) Del Río, A.; Coto, B.; Pando, C.; Renuncio, J. A. R. Vapor− Liquid Equilibria for the Binary Systems Decane + 1,1-Dimethylethyl Methyl Ether (MTBE) and Decane + 1,1-Dimethylpropyl Methyl Ether (TAME) at 308.15, 318.15 and 328.15 K. Fluid Phase Equilib. 2001, 187, 299−310. (2) Del Río, A.; Horstmann, S.; Renuncio, J. A. R.; Gmehling, J. Isothermal Vapor-Liquid Equilibrium and Excess Enthalpy Data for the Binary Systems Methyl Tert-Butyl Ether + Cyclohexane and Ethyl Tert-Butyl Ether + Cyclohexane, n-Hexane, and n-Heptane in a Temperature Range from 298.15 to 393.15 K. J. Chem. Eng. Data 2001, 46, 1181−1187. (3) Watanabe, T.; Honda, K.; Arai, Y. Measurement and Correlation of Isobaric Vapor-Liquid Equilibria for Binary and Ternary Systems Containing Methyl Tertiary Butyl Ether (MTBE), Methanol and Alkanes. Korean J. Chem. Eng. 2003, 20, 906−910. (4) Oh, J.-H.; Park, S.-J. Vapor-Liquid Equilibria for the Ternary Systems of Methyl Tert-Butyl Ether + Methanol + Methylcyclohexane and Methyl Tert-Butyl Ether + Methanol + n-Heptane and Constituent Binary Systems at 313.15 K. J. Chem. Eng. Data 2005, 50, 1564−1569. (5) Chamorro, C. R.; Segovia, J. J.; Martín, M. C.; Montero, E. A.; Villamañań , M. A. Phase Equilibrium Properties of Binary and Ternary Systems Containing Tert-Amyl Methyl Ether (TAME) as Oxygenate Additive and Gasoline Substitution Hydrocarbons at 313.15 K. Fluid Phase Equilib. 1999, 156, 73−87. (6) Kammerer, K.; Oswald, G.; Rezanova, E.; Silkenbäumer, D.; Lichtenthaler, R. N. Thermodynamic Excess Properties and VaporLiquid Equilibria of Binary and Ternary Mixtures Containing Methanol, Tert-Amyl Methyl Ether and an Alkane. Fluid Phase Equilib. 2000, 167, 223−241. (7) Alonso, C.; Montero, E. A.; Chamorro, C. R.; Segovia, J. J.; Martín, M. C.; Villamañań , M. A. Vapour−Liquid Equilibrium of Octane-Enhancing Additives in Gasolines 2. Total Pressure Data and gE for Binary and Ternary Mixtures Containing tert-Amyl methyl Ether (TAME), tert-Amyl Alcohol (TAOH) and n-Hexane. Fluid Phase Equilib. 2001, 182, 241−255. (8) Del Río, A.; Coto, B.; Pando, C.; Renuncio, J. A. R. Vapor-Liquid Equilibria for the Binary System Hexane + 1,1-Dimethylpropyl Methyl Ether at 298.15, 308.15, 318.15, and 328.15 K. Ind. Eng. Chem. Res. 2002, 41, 1364−1369. (9) Del Río, A.; Coto, B.; Pando, C.; Renuncio, J. A. R. Vapor-Liquid Equilibria and Excess Properties Of Octane + 1,1-Dimethylpropyl Methyl Ether (TAME) Mixtures. Fluid Phase Equilib. 2002, 200, 41− 51. (10) Mejía, A.; Segura, H.; Cartes, M.; Cifuentes, L.; Flores, M. Phase Equilibria and Interfacial Tensions in the Systems Methyl Tert-Butyl Ether + Acetone + Cyclohexane, Methyl Tert-Butyl Ether + Acetone and Methyl Tert-Butyl Ether + Cyclohexane. Fluid Phase Equilib. 2008, 273, 68−77. (11) Mejía, A.; Segura, H.; Cartes, M. Vapor-Liquid Equilibrium in the Binary Systems 2-Butanol + Tert -Amyl Methyl Ether, 2-Butanol + F
DOI: 10.1021/acs.jced.6b00587 J. Chem. Eng. Data XXXX, XXX, XXX−XXX
