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Measurement on vapor pressure, density and viscosity for binary mixtures of JP-10 and methylcyclohexane
Fluid Phase Equilibria 305 (2011) 192–196
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Fluid Phase Equilibria journal homepage: www.elsevier.com/locate/fluid
Measurement on vapor pressure, density and viscosity for binary mixtures of JP-10 and methylcyclohexane Yan Xing a,b , Xi Yang a , Wenjun Fang a,∗ , Yongsheng Guo a , Ruisen Lin a a b
Department of Chemistry, Zhejiang University, Hangzhou 310027, China Zibo Municipal Center for Disease Control and Prevention, Shandong 255026, China
a r t i c l e
i n f o
Article history: Received 21 January 2010 Received in revised form 30 March 2011 Accepted 30 March 2011 Available online 13 April 2011 Keywords: High density fuel Tricycle [5.2.1.02.6 ] decane (JP-10) Methylcyclohexane (MCH) Vapor pressure Density Viscosity
a b s t r a c t Measurement on bubble-point vapor pressure, density and viscosity at several temperatures for binary mixtures tricycle [5.2.1.02.6 ] decane (JP-10), a high density fuel, and methylcyclohexane (MCH) were carried out. The correlation between vapor pressures and equilibrium temperatures of each mixture was performed and the Antoine equation parameters were given correspondingly. The experimental VLE E data were correlated with the Wilson model. From the density and viscosity data, excess volume, Vm , and viscosity deviation, , for the binary mixtures were calculated and fitted with the Redlich–Kister equation. The viscosities correlated with several semi-empirical equations were also performed. The excess molar volumes and the viscosity deviations are negative over the entire composition range. © 2011 Elsevier B.V. All rights reserved.
1. Introduction Tricycle [5.2.1.02.6 ] decane (JP-10) is usually used as a high density fuel for missiles and a candidate fuel for supersonic aircrafts. The increased viscosities and large C/H ratios of such high density fuels suggest that difficulties will be encountered when attempting to spray them and that the flame radiation will be much stronger than that of a conventional fuel [1–4]. In order to improve the performance of a high density fuel, hydrocarbon components with relatively high volatility and low viscosity can be selected as additives. In this work, detailed measurements are performed to understand the volatility, volumetric and viscous prosperities of binary mixtures of JP-10 and methylcyclohexane (MCH). The results are provided to give important information on the property optimization of high-energy density hydrocarbon fuels. 2. Experimental 2.1. Materials The sample of JP-10 fuel was checked by GC–MS analysis with the mass purity of 98.5%. The MCH sample with 99.2% mass purity purchased from Sinopharm Chemical Reagent Company was dried
∗ Corresponding author. Tel.: +86 571 88981416; fax: +86 571 87951895. E-mail address: [email protected] (W. Fang). 0378-3812/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.fluid.2011.03.030
over 0.4 nm molecular sieves and degassed by ultrasound. Binary mixtures of JP-10 and MCH were prepared by directly weighing the constituent components to ±0.0001 g using a Mettler Toledo AL204 balance. The uncertainty of mole fraction was estimated to be ±10−4 . The physical properties of JP-10 and MCH are listed in Table 1, where Tb is the normal boiling point measured by the ebulliometer, is the density measured by vibrating-tube digital densimeter and is the viscosity measured by Ubbelohde viscometer, respectively. 2.2. Vapor pressure measurement On the basis of the ebulliometry, inclined ebulliometers with pump-like stirrers were used to measure the vapor pressures. The inclined structure can reduce the effect of height of liquid and the stirring function is useful for circulation of the sample. As a result, the reflux ratio R and liquid holdup can be reduced. The vapor–liquid equilibrium (VLE) temperatures of a sample and a reference material (ethanol) in two separate ebulliometers were measured under the same pressure with two standard platinum resistance thermometers connected to Keithley 195A digital multimeters. The equilibrium pressures were calculated from the VLE temperatures and the vapor pressure equation of ethanol [5]. Bubble-point pressures at various temperatures for the mixtures were measured over the equilibrium pressure range from about 8 kPa to 102 kPa. The uncertainty of the pressure was estimated to be ± 0.1 kPa.
Y. Xing et al. / Fluid Phase Equilibria 305 (2011) 192–196
193
Table 1 The physical properties of JP-10 and MCH. Compound
JP-10 MCH a b c d e f
(g cm−3 ) (298.15 K)
Tb (K)
(mPa s) (298.15 K)
Exptl.
Lit.
Exptl.
Lit.
Exptl.
Lit.
458.09 372.13
457.76a 373.96c
0.9314 0.76500
0.9318b 0.765d 0.7649e
2.739 0.678
2.767b 0.685f
Ref. [5]. Ref. [6]. Ref. [7]. Ref. [8]. Ref. [9]. Ref. [10].
Table 2 Bubble-point vapor pressure data for MCH (1) + JP-10 (2) binary mixtures. T (K)
p (kPa)
x1 = 0.0000
p (kPa)
T (K)
x1 = 0.0287
396.02 401.42 413.88 418.34 426.86 431.22 434.56 436.68 439.31 441.13 442.70 442.81 444.37 446.13 445.73 450.08 457.66
16.64 20.62 30.30 34.79 44.86 50.70 55.76 59.20 63.22 66.63 69.49 69.77 72.58 75.89 75.11 83.92 101.10
T (K)
p (kPa)
x1 = 0.5813 335.27 348.23 357.03 364.62 370.21 374.37 378.96 383.08 388.40 389.58 391.94 395.06 399.25
T (K)
x1 = 0.1341
384.81 393.52 404.29 406.54 407.42 413.04 418.45 425.66 427.18 429.27 430.70 433.84 437.06 443.62
13.78 19.94 31.94 35.01 36.47 44.42 53.57 65.64 68.04 73.55 76.33 82.52 87.46 101.46
T (K)
p (kPa)
x1 = 0.6770 11.95 19.63 27.50 35.90 43.55 50.54 57.81 65.53 77.45 80.86 85.56 93.63 102.10
328.70 340.83 347.98 354.44 362.42 368.38 373.07 376.28 379.21 384.00 386.67 390.22 394.23
p (kPa)
p (kPa)
x1 = 0.3728
372.45 380.83 387.60 390.60 399.09 403.49 408.59 415.57 416.83 422.43 422.32 426.24 429.23
13.96 21.89 30.49 35.24 47.42 53.68 62.47 73.44 76.10 85.46 85.60 92.00 101.11
T (K)
p (kPa)
x1 = 0.7697 11.70 19.52 25.48 33.11 43.27 51.99 59.96 65.28 70.99 79.89 86.09 93.57 102.80
T (K)
11.97 19.57 26.92 34.74 39.85 50.69 58.13 65.46 72.82 79.74 87.61 95.84 102.81
11.44 18.19 26.29 33.77 42.29 50.34 55.65 64.37 69.55 78.45 85.05 90.28 96.15 101.63
T (K)
p (kPa)
318.11 329.07 338.56 345.46 351.38 356.58 360.66 364.92 368.56 371.25 374.13 376.42 379.69
p (kPa)
x1 = 0.4804
345.26 357.35 365.72 372.48 379.83 383.94 386.91 391.34 393.68 397.99 401.06 403.64 405.44 407.68
x1 = 0.8473
320.22 332.06 340.50 347.63 351.64 358.99 363.32 367.17 370.76 373.92 377.12 380.32 382.89
T (K)
338.71 351.46 359.91 365.16 372.43 375.69 379.95 381.36 384.22 388.01 391.51 395.97 398.70 399.17
11.53 19.16 27.57 33.03 41.66 46.79 54.24 59.04 64.89 71.69 79.90 89.82 95.87 100.11
T (K)
p (kPa)
x1 = 1.0000 12.02 19.09 27.50 35.32 43.36 51.48 58.71 66.88 74.77 81.01 87.91 93.98 102.72
321.98 331.50 336.81 342.39 346.95 350.74 355.20 359.18 362.32 364.88 366.43 369.81 373.92
17.91 25.77 31.22 37.99 44.45 50.35 58.09 65.61 72.29 79.09 85.13 92.76 100.77
Table 3 Correlation results of vapor pressure by Antoine equation for MCH (1) + JP-10 (2) binary mixtures. x1
0.0000 0.0287 0.1341 0.3728 0.4804 0.5813 0.6770 0.7697 0.8473 1.0000
Temperature range (K)
396–458 384–444 372–430 345–408 338–400 335–400 328–395 320–383 318–380 321–374
Antoine equation coefficients −3
A
B × 10
C
11.71 8.22 6.84 11.65 12.19 12.86 9.80 12.88 12.78 13.62
2.16 5.80 2.74 1.83 2.07 2.50 1.14 2.50 2.41 2.87
153.53 281.79 307.34 148.02 127.43 94.86 174.23 79.62 84.34 55.01
AAD (kPa)
ARD (%)
0.21 0.60 0.62 0.54 0.86 0.56 0.26 0.05 0.04 2.20
0.49 1.29 1.03 1.25 1.68 1.00 0.64 0.09 0.07 3.87
194
Y. Xing et al. / Fluid Phase Equilibria 305 (2011) 192–196
Exp Ref. [7]
100
0.04
0.02
Δp/ pexp
p / kPa
80
60
40
A B C D E F G H I J
0.00
-0.02 20
-0.04 0
310
320
330
340
350
360
370
300
380
320
340
360
380
T/K Fig. 1. Experimental vapor pressures of MCH compared with the literature data.
400
420
440
460
480
500
T/K Fig. 3. Scatter plots of deviation distributions of the calculated values of the Antoine equation from the experimental vapor pressures for MCH (1) + JP-10 (2) binary mixtures: A, x1 = 0.0000; B, x1 = 0.0287; C, x1 = 0.1341; D, x1 = 0.3728; E, x1 = 0.4804; F, x1 = 0.5813; G, x1 = 0.6770; H, x1 = 0.7697; I, x1 = 0.8473; J, x1 = 1.0000.
2.3. Density and viscosity measurement Density, , was measured by a vibrating-tube digital densimeter (Anton Paar DMA5000M). The densimeter was calibrated with dry air. The precision of density measurement was estimated to be ±5 × 10−5 g cm−3 . The dynamic viscosity is calculated from the measured kinematic viscosity and density : =×
Table 4 Correlation parameters by the Wilson model. T (K)
12
21
378.15 383.15 388.15 393.15 398.15
2.890 2.309 2.207 2.132 2.081
0.241 0.421 0.442 0.459 0.469
(1) 3. Results and discussion
4.8
A B C D E F G H I J
4.4
ln P
4.0 3.6 3.2 2.8
3.1. Vapor pressures and phase diagrams The measured vapor pressure data for MCH compared with the literature data [7] are shown in Fig. 1. The average absolute deviation (AAD) and average relative deviation (ARD) [11] are calculated to be 0.45 kPa and 1.10%, respectively. Bubble-point vapor pressures at various temperatures for binary mixtures of JP-10 and MCH were then measured and the results are listed in Table 2. The plots of ln p against 1/T for the mixtures are shown in Fig. 2. The vapor pressure–temperature behaviors are
200 180
378.15 K 383.15 K 388.15 K 393.15 K 398.15 K
160 140 120
p / kPa
The kinematic viscosity was determined by using a Ubbelohde viscometer. The viscometer was filled with 15 mL solution and was submerged into a thermostatic bath with a resolution of 0.01 K. The flow time was measured with a stopwatch and was reproducible to be ±0.2 s. The viscometer was calibrated with twice-distilled water. Each viscosity value of the fluid was reported by averaging over three consecutive runs. The uncertainty of viscosity was within ±0.002 mPa s. s
100 80 60 40
2.4 0.0022
0.0024
0.0026
0.0028
0.0030
0.0032
-1
(1/ T) ( K ) Fig. 2. Temperature dependence of vapor pressures for MCH (1) + JP-10 (2) binary mixtures: A, x1 = 0.0000; B, x1 = 0.0287; C, x1 = 0.1341; D, x1 = 0.3728; E, x1 = 0.4804; F, x1 = 0.5813; G, x1 = 0.6770; H, x1 = 0.7697; I, x1 = 0.8473; J, x1 = 1.0000.
20 0
0.0
0.1
0.2
0.3
0.4
0.5
X1
0.6
0.7
0.8
0.9
Fig. 4. The p–x1 diagrams for the binary mixtures of MCH (1) + JP-10 (2).
1.0
Y. Xing et al. / Fluid Phase Equilibria 305 (2011) 192–196
a
Table 5 E ; viscosity, ; viscosity deviation, , for MCH (1) + JPDensity, ; excess volume, Vm 10 (2) binary mixtures at several temperatures. (mPa s)
(mPa s)
0.0000 −0.1476 −0.2356 −0.3218 −0.3397 −0.3582 −0.3238 −0.2687 −0.1851 −0.1055 0.0000
2.522 2.047 1.754 1.502 1.258 1.113 0.975 0.866 0.772 0.693 0.627
0.000 −0.209 −0.277 −0.320 −0.320 −0.307 −0.269 −0.210 −0.145 −0.077 0.000
0.92348 0.90345 0.88565 0.86872 0.84773 0.83382 0.81758 0.80158 0.78595 0.77116 0.75629
0.0000 −0.1564 −0.2487 −0.3383 −0.3569 −0.3745 −0.3420 −0.2802 −0.1968 −0.1135 0.0000
2.298 1.891 1.616 1.386 1.163 1.020 0.897 0.798 0.711 0.644 0.581
0.000 −0.166 −0.237 −0.278 −0.280 −0.280 −0.243 −0.189 −0.132 −0.067 0.000
0.91958 0.89948 0.88163 0.86467 0.84361 0.82966 0.81338 0.79733 0.78166 0.76683 0.75193
0.0000 −0.1606 −0.2557 −0.3515 −0.3700 −0.3877 −0.3550 −0.2894 −0.2035 −0.1171 0.0000
2.107 1.736 1.475 1.275 1.078 0.963 0.862 0.754 0.675 0.612 0.554
0.000 −0.153 −0.229 −0.258 −0.256 −0.241 −0.197 −0.168 −0.116 −0.059 0.000
-0.10 -0.15 -0.20
E
0.92741 0.90742 0.88967 0.87278 0.85185 0.83798 0.82176 0.80584 0.79022 0.77547 0.76065
0.00 -0.05
ΔV
303.15 K 0.0000 0.1404 0.2593 0.3693 0.4981 0.5813 0.6745 0.7630 0.8469 0.9245 1.0000 308.15 K 0.0000 0.1404 0.2593 0.3693 0.4981 0.5813 0.6745 0.7630 0.8469 0.9245 1.0000 313.15 K 0.0000 0.1404 0.2593 0.3693 0.4981 0.5813 0.6745 0.7630 0.8469 0.9245 1.0000
E Vm (cm3 mol−1 )
(g cm−3 )
-0.25 -0.30
303.15 K 308.15 K 313.15 K
-0.35 -0.40
b
0.0
0.1
0.2
0.7
0.8
0.9
1.0
-0.15 -0.20 -0.25 303.15 K 308.15 K 313.15 K
-0.30 -0.35
(2)
Table 6 E and by the Correlation parameters and standard deviation for Vm Redlich–Kister equation. A4
A1
A2
A3
−1.40161 −1.27363
−0.22050 0.22392
0.10895 −0.28884
0.05032 0.3431
0.0087 0.005
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
−1.46921 −1.13984
−0.21125 0.11577
0.08038 −0.10014
0.00184 0.25851
0.0091 0.004
−1.52351 −1.02589
−0.22120 0.29173
0.10360 −0.09621
−0.00578 −0.02786
0.0099 0.005
Fig. 5. Plots of excess molar volume (a) and viscosity deviation (b) versus mole fraction for MCH (1) + JP-10 (2) binary system.
shows the scatter plots of the ARD values. The results indicate that the Antoine equation well represents the vapor pressurestemperature behaviors over the entire experimental range. The vapor–liquid equilibrium (VLE) at constant temperatures are correlated with the Wilson model [12] of the liquid phase activity coefficients i ln i = −ln(xi − ij ) + xj [ij /(xi + ij xj ) − ji /(xj + ji xi )]
(i = / j) (3)
Table 7 Parameters and standard deviation for viscosity correlation with several semiempirical equations. Semi-empirical equation
Kendall–Monroe Grunberg–Nissan Hind Frenkel
0.6
-0.10
where p is the vapor pressure in kPa, T is the equilibrium temperature in K, and A, B, C are constants. Table 3 gives the Antoine constants, together with the errors given by AAD and ARD. Fig. 3
303.15 K E (cm3 mol−1 ) Vm (mPa s) 308.15 K E (cm3 mol−1 ) Vm (mPa s) 313.15 K E (cm3 mol−1 ) Vm (mPa s)
0.5
X1
X1
B T −C
Property
0.4
0.00
correlated with the Antoine equation: ln p = A −
0.3
-0.05
Δη
x1
195
A12
– −0.01 0.9 1.24
where ij and ji are adjustable parameters. Considering the ideal gaseous phase and non-ideal liquid phase, at vapor–liquid equilibrium, yi p = xi i p∗i
where xi and yi are the liquid and vapor phase mole fractions, respectively, p is the total pressure, p∗i is the vapor pressure of pure component i. The thermodynamic consistency of the VLE data is checked by the area test, and the value of I < 0.001. I=
(mPa s) 303.15 K
308.15 K
313.15 K
0.081 0.009 0.025 0.007
0.068 0.007 0.019 0.033
0.063 0.010 0.036 0.063
(4)
1 1 ln
0
2
dx1
(5)
The parameters of the Wilson model optimized from Eqs. (3) to (5) on the basis of the experimental vapor pressures are given in Table 4. The correlation results with the solid lines are shown in Fig. 4.
196
Y. Xing et al. / Fluid Phase Equilibria 305 (2011) 192–196
ln = x12 ln 1 + x22 ln 2 + 2x1 x2 ln A12
3.2. Density and viscosity Experimental data of density and viscosity, calculated values of E , and viscosity deviation, , for the binary mixexcess volume, Vm tures are given in Table 5. The excess volume and viscosity deviation are obtained from Eqs. (6) and (7). E Vm =
M1 x1 + M2 x2 −
M x 1 1 1
+
M2 x2 2
= − (x1 1 + x2 2 )
k
Ai (x1 − x2 )i−1
4. Conclusion
(7)
Measurements on bubble-point vapor pressure, density and viscosity at several temperatures for binary mixtures of tricycle [5.2.1.02.6 ] decane (JP-10) and methylcyclohexane (MCH) were carried out. Correlation between vapor pressures and equilibrium temperatures of each mixture was performed and the Antoine equation parameters were given. The experimental VLE data were correlated with Wilson model. From the density and viscosity E , and viscosity deviation, , for the data, excess volume, Vm binary mixtures were calculated and fitted with the Redlich–Kister equation. The viscosities correlated with semi-empirical equations were also performed. The excess molar volumes and the viscosity deviations are negative over the entire composition range, which are mainly induced by the different structural characteristics of the components. The thermodynamic data and calculations are helpful to adjust or control the volatility, fluidity and combustibility of high-energy density hydrocarbon fuels.
(8)
i=1 E or . A are the polynomial coefficients. The where Y implies Vm i correlated results are given in Table 6, in which the tabulated standard deviation, , is defined as
=
1/2 (Y − Ycal )2 n−k
(9)
where n is the number of datum points, k is the number of estimated parameters, Y is the experimental value and Ycal is the calculated value from Eq. (8). E , and the viscosity deviation, , against The excess volume, Vm the mole fraction for the investigated binary mixtures at different temperatures are shown in Fig. 5. It is observed that the excess molar volumes and the viscosity deviations are negative over the entire composition range. These excess values reflect the interactions between the molecules of JP-10 and MCH. Because both of JP-10 and MCH are nonpolar cyclic alkane compounds, the intermolecular forces between JP-10 and MCH are relatively weak and the structural characteristics of the components dominated the interactions. When the rigid and nonpolar JP-10 molecules are mixed with MCH molecules, the smaller molecules of MCH can E enter the space of JP-10 molecules and result in the negative Vm values. 3.3. Viscosity correlation Four typical semi-empirical equations [14–17] are employed to correlate the experimental viscosity data of the binary mixtures. Kendall–Monroe [14], Hind, Grunberg–Nissan and Frenkel [17] are respectively as the following equations. 1/3
= (x1 1 =
x12 1
1/3 3
+ x2 2 )
+ x22 2
+ 2x1 x2 A12
ln = x1 ln 1 + x2 ln 2 + x1 x2 A12
where A12 is an interaction parameter. The standard deviations and correlation parameters are shown in Table 7. The Grunberg–Nissan expression gives best correlation results among the four equations for the binary mixtures.
(6)
where Mi , xi , i and i are the molecular weight, mole fraction, density and viscosity of pure component i, respectively. and are the density and viscosity of the binary mixture, respectively. The excess volume or viscosity deviation as a function of composition was fitted to the Redlich–Kister type equation [13]: Y = x1 x2
(13)
(10) (11) (12)
Acknowledgements The authors are grateful for the financial supports from the National Natural Science Foundation of China (No. 20973154) and Scientific Research Foundation for Returned Scholars, Ministry of Education of China (No. J20080412). References [1] Z.H. Huang, H.B. Lu, D.M. Jiang, K. Zeng, B. Liu, J.Q. Zhang, X.B. Wang, Energy Fuels 19 (2005) 403–410. [2] G.D. Roy, J. Propulsion Power 16 (4) (2000) 546–551. [3] B.G. Mónica, M.B. Carlos, N.S. Horacio, Energy Fuels 18 (2004) 334–337. [4] P.E. Sojka, J.P. Gore, AIAA-1992-3378-786. [5] Y. Xing, Y.S. Guo, D. Li, W.J. Fang, R.S. Lin, Energy Fuels 21 (2007) 1048– 1051. [6] T.J. Bruno, M.L. Huber, A. Laesecke, E.W. Lemmon, R.A. Perkins, National Institute of Standards and Technology, NISTIR 6640, 2006. [7] M.C. Sánchez-Russinyol, A. Aucejo, S. Loras, J. Chem. Eng. Data 49 (2004) 1258–1262. [8] J.G. Baragi, M.I. Aralaguppi, M.Y. Kariduraganavar, S.S. Kulkarni, A.S. Kittur, T.M. Aminabhavi, J. Chem. Thermodyn. 38 (2006) 75–83. [9] N. Calvar, B. González, E. GÓmez, J. Canosa, J. Chem. Eng. Data 54 (2009) 1334–1339. [10] J.D. Ye, C.H. Tu, J. Chem. Eng. Data 50 (2005) 1060–1067. [11] W.J. Fang, Q.F. Lei, Fluid Phase Equilib. 213 (2003) 125–138. [12] G.M. Wilson, J. Am. Chem. Sci. 86 (1964) 127–129. [13] O.R. Redlich, A.T. Kister, Ind. Eng. Chem. 40 (1948) 345–348. [14] S.D. Chen, Q.F. Lei, W.J. Fang, Fluid Phase Equilib. 234 (2005) 22–33. [15] Q. Lei, Y. Hou, Fluid Phase Equilib. 154 (1999) 153–163. [16] Q. Lei, Y. Hou, R. Lin, Fluid Phase Equilib. 140 (1997) 221–231. [17] A.S. Al-Jimaz, J.A. Al-Kandary, A.M. Abdul-Latif, Fluid Phase Equilib. 218 (2004) 247–260.
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Fluid Phase Equilibria journal homepage: www.elsevier.com/locate/fluid
Measurement on vapor pressure, density and viscosity for binary mixtures of JP-10 and methylcyclohexane Yan Xing a,b , Xi Yang a , Wenjun Fang a,∗ , Yongsheng Guo a , Ruisen Lin a a b
Department of Chemistry, Zhejiang University, Hangzhou 310027, China Zibo Municipal Center for Disease Control and Prevention, Shandong 255026, China
a r t i c l e
i n f o
Article history: Received 21 January 2010 Received in revised form 30 March 2011 Accepted 30 March 2011 Available online 13 April 2011 Keywords: High density fuel Tricycle [5.2.1.02.6 ] decane (JP-10) Methylcyclohexane (MCH) Vapor pressure Density Viscosity
a b s t r a c t Measurement on bubble-point vapor pressure, density and viscosity at several temperatures for binary mixtures tricycle [5.2.1.02.6 ] decane (JP-10), a high density fuel, and methylcyclohexane (MCH) were carried out. The correlation between vapor pressures and equilibrium temperatures of each mixture was performed and the Antoine equation parameters were given correspondingly. The experimental VLE E data were correlated with the Wilson model. From the density and viscosity data, excess volume, Vm , and viscosity deviation, , for the binary mixtures were calculated and fitted with the Redlich–Kister equation. The viscosities correlated with several semi-empirical equations were also performed. The excess molar volumes and the viscosity deviations are negative over the entire composition range. © 2011 Elsevier B.V. All rights reserved.
1. Introduction Tricycle [5.2.1.02.6 ] decane (JP-10) is usually used as a high density fuel for missiles and a candidate fuel for supersonic aircrafts. The increased viscosities and large C/H ratios of such high density fuels suggest that difficulties will be encountered when attempting to spray them and that the flame radiation will be much stronger than that of a conventional fuel [1–4]. In order to improve the performance of a high density fuel, hydrocarbon components with relatively high volatility and low viscosity can be selected as additives. In this work, detailed measurements are performed to understand the volatility, volumetric and viscous prosperities of binary mixtures of JP-10 and methylcyclohexane (MCH). The results are provided to give important information on the property optimization of high-energy density hydrocarbon fuels. 2. Experimental 2.1. Materials The sample of JP-10 fuel was checked by GC–MS analysis with the mass purity of 98.5%. The MCH sample with 99.2% mass purity purchased from Sinopharm Chemical Reagent Company was dried
∗ Corresponding author. Tel.: +86 571 88981416; fax: +86 571 87951895. E-mail address: [email protected] (W. Fang). 0378-3812/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.fluid.2011.03.030
over 0.4 nm molecular sieves and degassed by ultrasound. Binary mixtures of JP-10 and MCH were prepared by directly weighing the constituent components to ±0.0001 g using a Mettler Toledo AL204 balance. The uncertainty of mole fraction was estimated to be ±10−4 . The physical properties of JP-10 and MCH are listed in Table 1, where Tb is the normal boiling point measured by the ebulliometer, is the density measured by vibrating-tube digital densimeter and is the viscosity measured by Ubbelohde viscometer, respectively. 2.2. Vapor pressure measurement On the basis of the ebulliometry, inclined ebulliometers with pump-like stirrers were used to measure the vapor pressures. The inclined structure can reduce the effect of height of liquid and the stirring function is useful for circulation of the sample. As a result, the reflux ratio R and liquid holdup can be reduced. The vapor–liquid equilibrium (VLE) temperatures of a sample and a reference material (ethanol) in two separate ebulliometers were measured under the same pressure with two standard platinum resistance thermometers connected to Keithley 195A digital multimeters. The equilibrium pressures were calculated from the VLE temperatures and the vapor pressure equation of ethanol [5]. Bubble-point pressures at various temperatures for the mixtures were measured over the equilibrium pressure range from about 8 kPa to 102 kPa. The uncertainty of the pressure was estimated to be ± 0.1 kPa.
Y. Xing et al. / Fluid Phase Equilibria 305 (2011) 192–196
193
Table 1 The physical properties of JP-10 and MCH. Compound
JP-10 MCH a b c d e f
(g cm−3 ) (298.15 K)
Tb (K)
(mPa s) (298.15 K)
Exptl.
Lit.
Exptl.
Lit.
Exptl.
Lit.
458.09 372.13
457.76a 373.96c
0.9314 0.76500
0.9318b 0.765d 0.7649e
2.739 0.678
2.767b 0.685f
Ref. [5]. Ref. [6]. Ref. [7]. Ref. [8]. Ref. [9]. Ref. [10].
Table 2 Bubble-point vapor pressure data for MCH (1) + JP-10 (2) binary mixtures. T (K)
p (kPa)
x1 = 0.0000
p (kPa)
T (K)
x1 = 0.0287
396.02 401.42 413.88 418.34 426.86 431.22 434.56 436.68 439.31 441.13 442.70 442.81 444.37 446.13 445.73 450.08 457.66
16.64 20.62 30.30 34.79 44.86 50.70 55.76 59.20 63.22 66.63 69.49 69.77 72.58 75.89 75.11 83.92 101.10
T (K)
p (kPa)
x1 = 0.5813 335.27 348.23 357.03 364.62 370.21 374.37 378.96 383.08 388.40 389.58 391.94 395.06 399.25
T (K)
x1 = 0.1341
384.81 393.52 404.29 406.54 407.42 413.04 418.45 425.66 427.18 429.27 430.70 433.84 437.06 443.62
13.78 19.94 31.94 35.01 36.47 44.42 53.57 65.64 68.04 73.55 76.33 82.52 87.46 101.46
T (K)
p (kPa)
x1 = 0.6770 11.95 19.63 27.50 35.90 43.55 50.54 57.81 65.53 77.45 80.86 85.56 93.63 102.10
328.70 340.83 347.98 354.44 362.42 368.38 373.07 376.28 379.21 384.00 386.67 390.22 394.23
p (kPa)
p (kPa)
x1 = 0.3728
372.45 380.83 387.60 390.60 399.09 403.49 408.59 415.57 416.83 422.43 422.32 426.24 429.23
13.96 21.89 30.49 35.24 47.42 53.68 62.47 73.44 76.10 85.46 85.60 92.00 101.11
T (K)
p (kPa)
x1 = 0.7697 11.70 19.52 25.48 33.11 43.27 51.99 59.96 65.28 70.99 79.89 86.09 93.57 102.80
T (K)
11.97 19.57 26.92 34.74 39.85 50.69 58.13 65.46 72.82 79.74 87.61 95.84 102.81
11.44 18.19 26.29 33.77 42.29 50.34 55.65 64.37 69.55 78.45 85.05 90.28 96.15 101.63
T (K)
p (kPa)
318.11 329.07 338.56 345.46 351.38 356.58 360.66 364.92 368.56 371.25 374.13 376.42 379.69
p (kPa)
x1 = 0.4804
345.26 357.35 365.72 372.48 379.83 383.94 386.91 391.34 393.68 397.99 401.06 403.64 405.44 407.68
x1 = 0.8473
320.22 332.06 340.50 347.63 351.64 358.99 363.32 367.17 370.76 373.92 377.12 380.32 382.89
T (K)
338.71 351.46 359.91 365.16 372.43 375.69 379.95 381.36 384.22 388.01 391.51 395.97 398.70 399.17
11.53 19.16 27.57 33.03 41.66 46.79 54.24 59.04 64.89 71.69 79.90 89.82 95.87 100.11
T (K)
p (kPa)
x1 = 1.0000 12.02 19.09 27.50 35.32 43.36 51.48 58.71 66.88 74.77 81.01 87.91 93.98 102.72
321.98 331.50 336.81 342.39 346.95 350.74 355.20 359.18 362.32 364.88 366.43 369.81 373.92
17.91 25.77 31.22 37.99 44.45 50.35 58.09 65.61 72.29 79.09 85.13 92.76 100.77
Table 3 Correlation results of vapor pressure by Antoine equation for MCH (1) + JP-10 (2) binary mixtures. x1
0.0000 0.0287 0.1341 0.3728 0.4804 0.5813 0.6770 0.7697 0.8473 1.0000
Temperature range (K)
396–458 384–444 372–430 345–408 338–400 335–400 328–395 320–383 318–380 321–374
Antoine equation coefficients −3
A
B × 10
C
11.71 8.22 6.84 11.65 12.19 12.86 9.80 12.88 12.78 13.62
2.16 5.80 2.74 1.83 2.07 2.50 1.14 2.50 2.41 2.87
153.53 281.79 307.34 148.02 127.43 94.86 174.23 79.62 84.34 55.01
AAD (kPa)
ARD (%)
0.21 0.60 0.62 0.54 0.86 0.56 0.26 0.05 0.04 2.20
0.49 1.29 1.03 1.25 1.68 1.00 0.64 0.09 0.07 3.87
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Y. Xing et al. / Fluid Phase Equilibria 305 (2011) 192–196
Exp Ref. [7]
100
0.04
0.02
Δp/ pexp
p / kPa
80
60
40
A B C D E F G H I J
0.00
-0.02 20
-0.04 0
310
320
330
340
350
360
370
300
380
320
340
360
380
T/K Fig. 1. Experimental vapor pressures of MCH compared with the literature data.
400
420
440
460
480
500
T/K Fig. 3. Scatter plots of deviation distributions of the calculated values of the Antoine equation from the experimental vapor pressures for MCH (1) + JP-10 (2) binary mixtures: A, x1 = 0.0000; B, x1 = 0.0287; C, x1 = 0.1341; D, x1 = 0.3728; E, x1 = 0.4804; F, x1 = 0.5813; G, x1 = 0.6770; H, x1 = 0.7697; I, x1 = 0.8473; J, x1 = 1.0000.
2.3. Density and viscosity measurement Density, , was measured by a vibrating-tube digital densimeter (Anton Paar DMA5000M). The densimeter was calibrated with dry air. The precision of density measurement was estimated to be ±5 × 10−5 g cm−3 . The dynamic viscosity is calculated from the measured kinematic viscosity and density : =×
Table 4 Correlation parameters by the Wilson model. T (K)
12
21
378.15 383.15 388.15 393.15 398.15
2.890 2.309 2.207 2.132 2.081
0.241 0.421 0.442 0.459 0.469
(1) 3. Results and discussion
4.8
A B C D E F G H I J
4.4
ln P
4.0 3.6 3.2 2.8
3.1. Vapor pressures and phase diagrams The measured vapor pressure data for MCH compared with the literature data [7] are shown in Fig. 1. The average absolute deviation (AAD) and average relative deviation (ARD) [11] are calculated to be 0.45 kPa and 1.10%, respectively. Bubble-point vapor pressures at various temperatures for binary mixtures of JP-10 and MCH were then measured and the results are listed in Table 2. The plots of ln p against 1/T for the mixtures are shown in Fig. 2. The vapor pressure–temperature behaviors are
200 180
378.15 K 383.15 K 388.15 K 393.15 K 398.15 K
160 140 120
p / kPa
The kinematic viscosity was determined by using a Ubbelohde viscometer. The viscometer was filled with 15 mL solution and was submerged into a thermostatic bath with a resolution of 0.01 K. The flow time was measured with a stopwatch and was reproducible to be ±0.2 s. The viscometer was calibrated with twice-distilled water. Each viscosity value of the fluid was reported by averaging over three consecutive runs. The uncertainty of viscosity was within ±0.002 mPa s. s
100 80 60 40
2.4 0.0022
0.0024
0.0026
0.0028
0.0030
0.0032
-1
(1/ T) ( K ) Fig. 2. Temperature dependence of vapor pressures for MCH (1) + JP-10 (2) binary mixtures: A, x1 = 0.0000; B, x1 = 0.0287; C, x1 = 0.1341; D, x1 = 0.3728; E, x1 = 0.4804; F, x1 = 0.5813; G, x1 = 0.6770; H, x1 = 0.7697; I, x1 = 0.8473; J, x1 = 1.0000.
20 0
0.0
0.1
0.2
0.3
0.4
0.5
X1
0.6
0.7
0.8
0.9
Fig. 4. The p–x1 diagrams for the binary mixtures of MCH (1) + JP-10 (2).
1.0
Y. Xing et al. / Fluid Phase Equilibria 305 (2011) 192–196
a
Table 5 E ; viscosity, ; viscosity deviation, , for MCH (1) + JPDensity, ; excess volume, Vm 10 (2) binary mixtures at several temperatures. (mPa s)
(mPa s)
0.0000 −0.1476 −0.2356 −0.3218 −0.3397 −0.3582 −0.3238 −0.2687 −0.1851 −0.1055 0.0000
2.522 2.047 1.754 1.502 1.258 1.113 0.975 0.866 0.772 0.693 0.627
0.000 −0.209 −0.277 −0.320 −0.320 −0.307 −0.269 −0.210 −0.145 −0.077 0.000
0.92348 0.90345 0.88565 0.86872 0.84773 0.83382 0.81758 0.80158 0.78595 0.77116 0.75629
0.0000 −0.1564 −0.2487 −0.3383 −0.3569 −0.3745 −0.3420 −0.2802 −0.1968 −0.1135 0.0000
2.298 1.891 1.616 1.386 1.163 1.020 0.897 0.798 0.711 0.644 0.581
0.000 −0.166 −0.237 −0.278 −0.280 −0.280 −0.243 −0.189 −0.132 −0.067 0.000
0.91958 0.89948 0.88163 0.86467 0.84361 0.82966 0.81338 0.79733 0.78166 0.76683 0.75193
0.0000 −0.1606 −0.2557 −0.3515 −0.3700 −0.3877 −0.3550 −0.2894 −0.2035 −0.1171 0.0000
2.107 1.736 1.475 1.275 1.078 0.963 0.862 0.754 0.675 0.612 0.554
0.000 −0.153 −0.229 −0.258 −0.256 −0.241 −0.197 −0.168 −0.116 −0.059 0.000
-0.10 -0.15 -0.20
E
0.92741 0.90742 0.88967 0.87278 0.85185 0.83798 0.82176 0.80584 0.79022 0.77547 0.76065
0.00 -0.05
ΔV
303.15 K 0.0000 0.1404 0.2593 0.3693 0.4981 0.5813 0.6745 0.7630 0.8469 0.9245 1.0000 308.15 K 0.0000 0.1404 0.2593 0.3693 0.4981 0.5813 0.6745 0.7630 0.8469 0.9245 1.0000 313.15 K 0.0000 0.1404 0.2593 0.3693 0.4981 0.5813 0.6745 0.7630 0.8469 0.9245 1.0000
E Vm (cm3 mol−1 )
(g cm−3 )
-0.25 -0.30
303.15 K 308.15 K 313.15 K
-0.35 -0.40
b
0.0
0.1
0.2
0.7
0.8
0.9
1.0
-0.15 -0.20 -0.25 303.15 K 308.15 K 313.15 K
-0.30 -0.35
(2)
Table 6 E and by the Correlation parameters and standard deviation for Vm Redlich–Kister equation. A4
A1
A2
A3
−1.40161 −1.27363
−0.22050 0.22392
0.10895 −0.28884
0.05032 0.3431
0.0087 0.005
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
−1.46921 −1.13984
−0.21125 0.11577
0.08038 −0.10014
0.00184 0.25851
0.0091 0.004
−1.52351 −1.02589
−0.22120 0.29173
0.10360 −0.09621
−0.00578 −0.02786
0.0099 0.005
Fig. 5. Plots of excess molar volume (a) and viscosity deviation (b) versus mole fraction for MCH (1) + JP-10 (2) binary system.
shows the scatter plots of the ARD values. The results indicate that the Antoine equation well represents the vapor pressurestemperature behaviors over the entire experimental range. The vapor–liquid equilibrium (VLE) at constant temperatures are correlated with the Wilson model [12] of the liquid phase activity coefficients i ln i = −ln(xi − ij ) + xj [ij /(xi + ij xj ) − ji /(xj + ji xi )]
(i = / j) (3)
Table 7 Parameters and standard deviation for viscosity correlation with several semiempirical equations. Semi-empirical equation
Kendall–Monroe Grunberg–Nissan Hind Frenkel
0.6
-0.10
where p is the vapor pressure in kPa, T is the equilibrium temperature in K, and A, B, C are constants. Table 3 gives the Antoine constants, together with the errors given by AAD and ARD. Fig. 3
303.15 K E (cm3 mol−1 ) Vm (mPa s) 308.15 K E (cm3 mol−1 ) Vm (mPa s) 313.15 K E (cm3 mol−1 ) Vm (mPa s)
0.5
X1
X1
B T −C
Property
0.4
0.00
correlated with the Antoine equation: ln p = A −
0.3
-0.05
Δη
x1
195
A12
– −0.01 0.9 1.24
where ij and ji are adjustable parameters. Considering the ideal gaseous phase and non-ideal liquid phase, at vapor–liquid equilibrium, yi p = xi i p∗i
where xi and yi are the liquid and vapor phase mole fractions, respectively, p is the total pressure, p∗i is the vapor pressure of pure component i. The thermodynamic consistency of the VLE data is checked by the area test, and the value of I < 0.001. I=
(mPa s) 303.15 K
308.15 K
313.15 K
0.081 0.009 0.025 0.007
0.068 0.007 0.019 0.033
0.063 0.010 0.036 0.063
(4)
1 1 ln
0
2
dx1
(5)
The parameters of the Wilson model optimized from Eqs. (3) to (5) on the basis of the experimental vapor pressures are given in Table 4. The correlation results with the solid lines are shown in Fig. 4.
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Y. Xing et al. / Fluid Phase Equilibria 305 (2011) 192–196
ln = x12 ln 1 + x22 ln 2 + 2x1 x2 ln A12
3.2. Density and viscosity Experimental data of density and viscosity, calculated values of E , and viscosity deviation, , for the binary mixexcess volume, Vm tures are given in Table 5. The excess volume and viscosity deviation are obtained from Eqs. (6) and (7). E Vm =
M1 x1 + M2 x2 −
M x 1 1 1
+
M2 x2 2
= − (x1 1 + x2 2 )
k
Ai (x1 − x2 )i−1
4. Conclusion
(7)
Measurements on bubble-point vapor pressure, density and viscosity at several temperatures for binary mixtures of tricycle [5.2.1.02.6 ] decane (JP-10) and methylcyclohexane (MCH) were carried out. Correlation between vapor pressures and equilibrium temperatures of each mixture was performed and the Antoine equation parameters were given. The experimental VLE data were correlated with Wilson model. From the density and viscosity E , and viscosity deviation, , for the data, excess volume, Vm binary mixtures were calculated and fitted with the Redlich–Kister equation. The viscosities correlated with semi-empirical equations were also performed. The excess molar volumes and the viscosity deviations are negative over the entire composition range, which are mainly induced by the different structural characteristics of the components. The thermodynamic data and calculations are helpful to adjust or control the volatility, fluidity and combustibility of high-energy density hydrocarbon fuels.
(8)
i=1 E or . A are the polynomial coefficients. The where Y implies Vm i correlated results are given in Table 6, in which the tabulated standard deviation, , is defined as
=
1/2 (Y − Ycal )2 n−k
(9)
where n is the number of datum points, k is the number of estimated parameters, Y is the experimental value and Ycal is the calculated value from Eq. (8). E , and the viscosity deviation, , against The excess volume, Vm the mole fraction for the investigated binary mixtures at different temperatures are shown in Fig. 5. It is observed that the excess molar volumes and the viscosity deviations are negative over the entire composition range. These excess values reflect the interactions between the molecules of JP-10 and MCH. Because both of JP-10 and MCH are nonpolar cyclic alkane compounds, the intermolecular forces between JP-10 and MCH are relatively weak and the structural characteristics of the components dominated the interactions. When the rigid and nonpolar JP-10 molecules are mixed with MCH molecules, the smaller molecules of MCH can E enter the space of JP-10 molecules and result in the negative Vm values. 3.3. Viscosity correlation Four typical semi-empirical equations [14–17] are employed to correlate the experimental viscosity data of the binary mixtures. Kendall–Monroe [14], Hind, Grunberg–Nissan and Frenkel [17] are respectively as the following equations. 1/3
= (x1 1 =
x12 1
1/3 3
+ x2 2 )
+ x22 2
+ 2x1 x2 A12
ln = x1 ln 1 + x2 ln 2 + x1 x2 A12
where A12 is an interaction parameter. The standard deviations and correlation parameters are shown in Table 7. The Grunberg–Nissan expression gives best correlation results among the four equations for the binary mixtures.
(6)
where Mi , xi , i and i are the molecular weight, mole fraction, density and viscosity of pure component i, respectively. and are the density and viscosity of the binary mixture, respectively. The excess volume or viscosity deviation as a function of composition was fitted to the Redlich–Kister type equation [13]: Y = x1 x2
(13)
(10) (11) (12)
Acknowledgements The authors are grateful for the financial supports from the National Natural Science Foundation of China (No. 20973154) and Scientific Research Foundation for Returned Scholars, Ministry of Education of China (No. J20080412). References [1] Z.H. Huang, H.B. Lu, D.M. Jiang, K. Zeng, B. Liu, J.Q. Zhang, X.B. Wang, Energy Fuels 19 (2005) 403–410. [2] G.D. Roy, J. Propulsion Power 16 (4) (2000) 546–551. [3] B.G. Mónica, M.B. Carlos, N.S. Horacio, Energy Fuels 18 (2004) 334–337. [4] P.E. Sojka, J.P. Gore, AIAA-1992-3378-786. [5] Y. Xing, Y.S. Guo, D. Li, W.J. Fang, R.S. Lin, Energy Fuels 21 (2007) 1048– 1051. [6] T.J. Bruno, M.L. Huber, A. Laesecke, E.W. Lemmon, R.A. Perkins, National Institute of Standards and Technology, NISTIR 6640, 2006. [7] M.C. Sánchez-Russinyol, A. Aucejo, S. Loras, J. Chem. Eng. Data 49 (2004) 1258–1262. [8] J.G. Baragi, M.I. Aralaguppi, M.Y. Kariduraganavar, S.S. Kulkarni, A.S. Kittur, T.M. Aminabhavi, J. Chem. Thermodyn. 38 (2006) 75–83. [9] N. Calvar, B. González, E. GÓmez, J. Canosa, J. Chem. Eng. Data 54 (2009) 1334–1339. [10] J.D. Ye, C.H. Tu, J. Chem. Eng. Data 50 (2005) 1060–1067. [11] W.J. Fang, Q.F. Lei, Fluid Phase Equilib. 213 (2003) 125–138. [12] G.M. Wilson, J. Am. Chem. Sci. 86 (1964) 127–129. [13] O.R. Redlich, A.T. Kister, Ind. Eng. Chem. 40 (1948) 345–348. [14] S.D. Chen, Q.F. Lei, W.J. Fang, Fluid Phase Equilib. 234 (2005) 22–33. [15] Q. Lei, Y. Hou, Fluid Phase Equilib. 154 (1999) 153–163. [16] Q. Lei, Y. Hou, R. Lin, Fluid Phase Equilib. 140 (1997) 221–231. [17] A.S. Al-Jimaz, J.A. Al-Kandary, A.M. Abdul-Latif, Fluid Phase Equilib. 218 (2004) 247–260.