Article pubs.acs.org/jced
Measurement and Correlation of the Vapor Pressure of a Series of α‑Pinene Derivatives YingShu Wang, NaRu Huang, BingHui Xu, BiYu Wang,* and ZhengShuai Bai College of Chemistry and Chemical Engineering, Fuzhou University, 350108, Xueyuan Road No. 2, Shangjie Town, Minhou Country, Fuzhou, China ABSTRACT: The saturated vapor pressures of a series of α-pinene derivatives including camphene, isobornyl acetate, (±)-limonene, dihydromyrcenol, pinane, and dihydromyrcene were determined at the pressure ranging from (0.8 to 50.0) kPa by the boiling point method. Good agreement of the correlated values was obtained when the experimental data of vapor pressure and temperature were correlated by the Antoine equation, and the parameters A, B, and C were estimated. The molar enthalpies of vaporization ΔvapHm of these compounds were estimated within the experimental temperature range by the Clausius−Clapeyron equation. Furthermore, the reliability of regressed parameters obtained from the Antoine equation in the range of experimental data was verified.
1. INTRODUCTION α-Pinene ((1S,5S)-2,6,6-trimethyl bicyclo[3.1.1]hept-2-ene ((−)-α-pinene)) can be transformed into a variety of valuable product such as camphor, camphene (3,3-dimethyl-2-methylenenorcamphane), isobornyl acetate ((1R,2R,4S)-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl acetate), (±)-limonene (1-methyl-4(1-methylethenyl)cyclohexene), dihydromyrcenol, (DHMOH, 2,6-dimethyl-7-octen-2-ol), pinane (2,6,6-trimethyl-bicyclo(3.1.1)heptan), and dihydromyrcene (DHM, 3,7-dimethyl-1,6octadiene) by different chemical reactions and processes. These chemicals are useful synthetic intermediates, which are commercially important in pharmaceuticals, perfumes, flavors, cosmetics, and fragrance industries.1 Isomerization of α-pinene2,3 to camphene and acetoxylation of camphene4,5 to isobornyl acetate are the key steps of synthesizing camphor6 using α-pinene as the starting material. Isomerization of α-pinene also can give the industrial useful product of (±)-limonene. Meanwhile, as an important component in the artificial flavor product, dihydromyrcenol was mainly obtained via the hydrogenation of α-pinene,7 thermal isomerization of pinane,8 and then hydration of DHM.9 The saturated vapor pressure and the molar enthalpy of vaporization were very important thermodynamic parameters and can be used in the design and operation of multicomponent systems.10 However, only a few experimental vapor pressure data were reported.11−19 Stull et al. reported seven experimental vapor pressure data for camphene. Zhu et al. reported the vapor pressure data of pinane in pressure range (59.34 to 93.93) kPa. Yang et al. measured vapor pressures of DHMOH and DHM at the minimum pressure of 2.6 kPa and 2.4 kPa, respectively. Most of the reported experimental pressure vapor data were based on the atmospheric pressure for these compounds, and the temperature dependence of vapor pressure and related thermodynamic properties of isobornyl acetate were not found. As we know, the vacuum pressure of industrial distillation for a series of α-pinene derivatives was generally under 10 kPa. In this work, the vapor pressures of camphene, isobornyl acetate, (±)-limonene, dihydromyrcenol, (DHMOH), pinane, and © 2014 American Chemical Society
dihydromyrcene (DHM) were determined by boiling point method in the range of (0.8 to 50) kPa. The vapor pressure data were fitted by the Antoine equation, and the parameters A, B, and C were obtained. The molar enthalpies of vaporization for each compound were calculated, and the reliability of regressed parameters obtained from the Antoine equation in the range of experimental data was verified.
2. EXPERIMENTAL SECTION 2.1. Chemicals. The source, purity, and purification method were listed in Table 1.The purity of the sample was determined by a gas chromatograph (GC-2010, Shimadzu Corporation) equipped with a flame ionization detector (FID). A DB-5MS column (30 m × 0.25 mm × 0.25 μm) was used with a temperature-programmed analysis. Column temperature: 373 K maintain 0 min, 10 K·min−1 heating for 8 min, 453 K maintain 0 min, 20 K·min−1 heating for 1 min, 473 K maintain 0 min; injection mode, split ratio 50/1; injector temperature, 493 K and detector temperature, 523 K; carrier gas, helium; injected volume 0.2 μL liquid sample. 2.2. Apparatus and Procedure. In this work, the boiling point method was applied to measure the vapor pressures for these chemicals. The similar apparatus for vapor pressure data measurement had been described previously.20,21 It was composed of a heating system including a three-neck flask (250 cm3) and a heating magnetic whisk, a measurement system, and a vacuum control system, as shown in Figure 1. The pressure of the system was adjusted by a vacuum pump, an absolute pressure transmitter (Shanghai Welltech Automation Co., Ltd.) with the accuracy of ± 0.001 kPa and an intelligent control instrument (HP604 model, Zhejiang Chint Electric Co., Ltd.). The temperature was measured by a precision mercury-in-glass thermometer with the accuracy of ± 0.1 K. Received: October 31, 2013 Accepted: January 17, 2014 Published: February 4, 2014 494
dx.doi.org/10.1021/je400951k | J. Chem. Eng. Data 2014, 59, 494−498
Journal of Chemical & Engineering Data
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Table 1. Materials Description
a
materials
sources
purity (mass fraction)
purification method
CAS NO.
1-octanol camphene (±)-limonene isobornyl acetate pinane DHMa DHMOHb
Sinopharm Grop Chemical Co., Ltd. FuJian Qing Song Co., Ltd. Tokyo Chemical Industry Co., Ltd. FuJian Qing Song Co., Ltd. Huaian National Spices Industry Co., Ltd. Jiangxi Kaiyuan Fragrance Co., Ltd. Huaian National Spices Industry Co., Ltd.
≥ 0.99 ≥ 0.984 (cis-: 0.963, trans: 0.21) ≥ 0.968 ≥ 0.99 ≥ 0.997 (cis: 0.978, trans: 0.19) ≥ 0.99 ≥ 0.99
none vacuum distillation none vacuum distillation vacuum distillation vacuum distillation none
111-87-5 79-92-5 138-86-3 125-12-2 473-55-2 2436-90-0 18479-58-8
DHM is dihydromyrene. bDHMOH is dihydromyrcenol.
The standard uncertainty of the temperature measurement is 0.1 K. The relative uncertainty of the pressure sensor is estimated within 0.00015, and the vapor pressure reproducibility for three times measurement of each equilibrium point is within 0.003. The relative combined standard uncertainty uc,r of the vapor pressure is estimated within 0.003; thus Ur = k·uc,r defines a coverage factor k = 2 for a level of confidence of approximately 95 %. The relative expanded uncertainty of the vapor pressure Ur(p) is 0.006. 2.3. Validation Experiments. The vapor pressure of water and 1-octanol was measured to validate the reliability and accuracy of the apparatus, which was consistent with the reported data,22,23 and the results are listed in Table 2. It could be seen that the maximum absolute deviations of water and 1-octanol were no more than 0.359 kPa and 0.293 kPa, respectively, together with the root-mean square deviations (rmsd’s) of 0.138 kPa and 0.125 kPa. It indicated that our apparatus was reliable and the measurement was feasible.
Figure 1. Schematic diagram for the measurement of saturated vapor pressure. (1) Three-neck flask; (2) condenser; (3) thermometer used for dew neck calibration; (4) thermometer used for measurement; (5) magnetic whisk; (6) absolute pressure transmitter; (7) intelligent controller; (8) electromagnetic valve; (9), (10) valve; (11) pressure buffer tank; (12) vacuum pump.
First, the sample of 100 mL was charged into the three-neck flask. The intelligent controller was set to the required value. The vacuum pump was started, and then the valve “9” was closed. Second, when the intelligent controller was controlled at the desired value, the valve “10” was closed immediately. Then, the pressure of the system was automatically controlled by the intelligent controller and electromagnetic valve “8”. Finally, the sample was heated by heating magnetic whisk gradually and partially evaporated. The vapor was condensed and completely mixed with the liquid phase. When the system was stable and the equilibrium was established, the temperature and pressure were recorded. This procedure was usually finished within 30 min. Certain vapor pressures of these compounds were measured when increasing pressure. The experimental temperature and pressure values of each stage were measured three times to guarantee the reliability and accuracy of the experimental data.
3. RESULTS AND DISCUSSION 3.1. Regressed Parameters of the Antoine Equation and Vapor-Pressure Data. The measured temperatures for these compounds at pressures ranging from (0.8 to 50) kPa are listed in Table 3 and Table 4. The Antoine equation correlating the measured data of vapor pressures can be determined by eq 1, where ps/kPa is the vapor pressure and T/K is the temperature. Parameters A, B, and C were calculated by using a regression method of Hooke−Jeeves pattern search with Matlab software. Table 5 gave the parameters of A, B, and C for these compounds, respectively. B log ps = A − (1) T+C Tables 3 and 4 showed the maximum absolute deviations (AD) were 0.312 kPa, 0.587 kPa, 0.148 kPa, 0.257 kPa,
Table 2. Vapor Pressure Data for Water and 1-Octanola water no.
Texp/K
1 292.54 2 303.48 3 310.23 4 315.78 5 319.82 6 327.62 7 334.02 8 343.07 9 max absolute deviation rmsdc
1-octanol
ps,exp/kPa
ps,lit/kPa
ADb/kPa
Texp/K
ps,exp/kPa
ps,cal/kPa
ADb/kPa
2.160 4.430 6.190 8.497 10.498 15.712 20.832 30.040
2.178 4.459 6.231 8.583 10.546 15.649 20.744 29.681
0.018 0.029 0.041 0.086 0.048 0.063 0.088 0.359
358.05 363.99 368.73 381.98 393.36 401.09 410.79 418.15 429.75
1.088 1.527 2.016 4.073 7.08 10.039 15.039 20.032 30.198
1.087 1.545 2.022 4.070 7.026 9.924 14.894 19.900 30.491
0.001 0.018 0.006 0.003 0.054 0.115 0.145 0.132 0.293 0.293 0.125
0.359 0.138
a
The standard uncertainty u is u(T) = 0.1 K, and the relative expanded uncertainty Ur is Ur(p) = 0.006 (0.95 level of confidence). bAbsolute deviations (AD)water = |ps,exp − ps,lit|; Absolute deviations (AD)1‑octanol = |ps,exp − ps,cal|, where ps,exp is the experimental value, ps,lit is the literature value, and ps,cal is calculated by the Wagner equation. crmsd = (∑ni=1((Mi,exp − Mi,cal)2)/n)0.5 where n is the number of data points and M represents p. 495
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Table 3. Vapor Pressure for the Camphene, Isobornyl Acetate, and (±)-Limonenea camphene
isobornyl acetate
(±)-limonene
Texp/K
ps,exp/kPa
ps,cal/kPa
ADb/kPa
Texp/K
ps,exp/kPa
ps,cal/kPa
ADb/kPa
Texp/K
ps,exp/kPa
ps,cal/kPa
ADb/kPa
309.70 322.72 331.06 337.27 342.04 346.21 350.07 353.23 355.98 358.83 365.69 369.58 378.51 384.98 390.65 399.95 407.61
1.007 2.026 3.053 4.056 5.043 6.007 7.068 8.029 9.003 10.074 13.055 15.064 20.124 25.003 29.955 40.038 50.016
1.007 2.026 3.053 4.072 5.033 6.021 7.073 8.041 8.970 10.024 12.973 14.937 20.359 25.200 30.150 39.923 49.704
0.000 0.000 0.000 0.016 0.010 0.014 0.005 0.012 0.033 0.050 0.082 0.127 0.235 0.197 0.195 0.115 0.312
381.09 390.08 397.10 402.69 407.45 411.60 414.92 418.66 421.67 427.93 434.61 442.35 452.64 457.89 463.13 468.12 472.63
2.004 3.021 4.013 5.010 6.023 7.027 8.014 9.042 10.032 12.038 15.024 19.119 26.010 30.148 35.001 40.123 45.253
2.041 3.007 4.005 4.985 5.970 6.955 7.935 8.937 9.913 12.224 15.160 19.254 26.042 30.181 34.820 39.747 44.666
0.037 0.014 0.008 0.025 0.053 0.072 0.079 0.105 0.119 0.186 0.136 0.135 0.032 0.033 0.181 0.376 0.587
346.96 353.19 358.22 362.25 366.08 369.31 372.54 375.27 379.93 386.12 394.56 401.29 407.10 416.21 420.21
3.010 4.013 5.008 6.002 7.018 8.018 9.043 10.023 12.035 15.044 20.006 25.044 30.085 39.911 44.804
3.017 4.021 5.021 5.965 6.993 7.970 9.057 10.067 12.002 15.031 20.131 25.124 30.205 39.763 44.659
0.007 0.008 0.013 0.037 0.025 0.048 0.014 0.044 0.033 0.013 0.125 0.080 0.120 0.148 0.145
a
The standard uncertainty u is u(T) = 0.1 K, and the relative expanded uncertainty Ur is Ur(p) = 0.006 (0.95 level of confidence). bAbsolute deviations (AD) = |ps,exp − ps,cal|, where ps,exp is the experimental value and ps,cal is calculated by the Antoine equation.
Table 4. Vapor Pressure for Pinane, DHMOH, and DHMa pinane
DHMOH
DHM
Texp/K
ps,exp/kPa
ps,cal/kPa
ADb/kPa
Texp/K
ps,exp/kPa
ps,cal/kPa
ADb/kPa
Texp/K
ps,exp/kPa
ps,cal/kPa
ADb/kPa
330.27 338.50 344.71 349.80 357.77 360.94 366.78 373.45 379.03 385.72 392.24 397.94 407.54 415.01
2.040 3.030 4.015 4.980 7.015 8.015 10.035 13.040 16.050 20.040 25.055 30.040 40.030 50.030
2.029 3.023 4.022 5.036 7.045 8.012 10.083 12.968 15.874 20.052 24.937 29.973 40.287 50.145
0.011 0.007 0.007 0.056 0.030 0.003 0.048 0.072 0.176 0.012 0.118 0.067 0.257 0.115
351.52 354.37 360.41 365.22 372.31 377.40 381.86 388.97 394.58 401.82 407.61 415.17 421.59
0.820 1.015 1.516 2.030 3.024 4.017 5.015 7.030 9.035 12.040 15.040 20.030 25.040
0.827 1.010 1.507 2.028 3.046 3.998 5.010 7.018 8.993 12.138 15.189 19.989 24.863
0.007 0.005 0.009 0.002 0.022 0.019 0.005 0.012 0.042 0.098 0.149 0.041 0.177
316.50 322.57 327.44 334.96 340.66 345.44 349.51 356.16 361.68 373.78 379.02 385.62 391.11
1.260 1.760 2.260 3.260 4.260 5.260 6.260 8.250 10.230 16.250 20.260 25.260 30.260
1.272 1.755 2.248 3.243 4.230 5.245 6.264 8.291 10.367 16.487 19.951 25.146 30.282
0.012 0.005 0.012 0.017 0.030 0.015 0.004 0.041 0.137 0.237 0.309 0.114 0.022
a
The standard uncertainty u is u(T) = 0.1 K, and the relative expanded uncertainty Ur is Ur(p) = 0.006 (0.95 level of confidence). bAbsolute deviations (AD) = |ps,exp − ps,cal|, where ps,exp is the experimental value and ps,cal is calculated by the Antoine equation.
Table 5. Regressed Antoine Parameters and ARD for All Six Compounds
a
Antoine parameters
A
B
C
R2
rmsda/kPa
camphene isobornyl acetate (±)-limonene pinane DHMOH DHM
5.6833 5.8612 5.7791 6.0518 4.5252 6.4904
1309.39 1596.92 1369.68 1520.85 683.56 1733.48
−79.1841 −93.4262 −88.5047 −65.5155 −203.1697 −45.0462
0.9994 0.9995 0.9997 0.9998 0.9967 0.9999
0.126 0.193 0.076 0.100 0.072 0.120
rmsd = (∑ni=1[(Mi,exp − Mi,cal)2)/n]0.5 where n is the number of data points and M represents p.
0.177 kPa, and 0.309 kPa for camphene, isobornyl acetate, (±)-limonene, pinane, DHMOH, and DHM, respectively. To evaluate the quality of the regressed parameters, the rmsd of vapor pressure between the experimental and the calculated values were calculated and listed in Table 5. The experimental data had an excellent agreement with the fitting values over the experimental pressure range (Figures 2 and 3).
Therefore, the Antoine parameters could meet the needs of engineering design and application. 3.2. Vaporization Enthalpies. The molar enthalpy of vaporization ΔvapHm played an important role in the design of a distillation process. The influence of pressure on ΔvapHm usually could be negligible over the temperature range studied, while the effect of temperature on ΔvapHm should not be neglected. 496
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Table 7. Comparison between the Calculated Value of Temperature by the Antoine Equation and Literature Value of Temperature T/K ps/kPa
material camphene
Figure 2. Comparison between experimental value and fitted value: ▲, experimental value of camphene; , fitted value of camphene; ■, experimental value of isobornyl acetate; ---, fitted value of isobornyl acetate; ●, experimental value of (±)-limonene; -·-, fitted value of (±)-limonene.
101.325 101.325 2.666 5.333 7.999 13.332 26.664 53.329 101.33 99.325 101.325 101.325 97.325 95.991 101.325
pinane
DHM
literature data 11
432.64 432.7412 333.5013 348.8013 358.1013 371.0013 390.6013 411.8113 433.6313 439.0912 438.1414 440.8915 426.6418 428.6419 431.6415
calc.
ADa/K
100 RDb
435.24 435.24 328.24 343.37 353.10 366.43 386.74 410.14 435.23 440.59 441.40 441.40 430.08 429.57 431.58
2.600 2.500 5.260 5.430 5.000 4.570 3.860 1.670 1.600 1.500 3.260 0.510 3.440 0.930 0.060
0.601 0.578 1.577 1.557 1.396 1.232 0.988 0.406 0.369 0.342 0.744 0.116 0.806 0.217 0.014
a Absolute deviations (AD) = |Ts,lit − Ts,cal|. bRelative deviations (RD) = (|Ts,lit − Ts,cal|/Ts,lit), where Ts,lit is the literature value and Ts,cal is calculated by the Antoine equation.
Δ vapHm = mT 2 − nT 3
Thus, eq 5 was obtained by the combination of eq 4 and eq 3. Parameter values of a, b, c, m, and n were displayed in Table 6, and the relationships between ΔvapHm and T were obtained. The value of ΔvapHm at each temperature can be calculated. If the influence of the temperature on ΔvapHm was also neglected, we can obtain eq 6 from eq 2.
Figure 3. Comparison between experimental value and fitted value: ▲, experimental value of pinane; , ,fitted value of pinane; ■, experimental value of DHMOH; ---, fitted value of DHMOH; ●, experimental value of DHM; -·-, fitted value of DHM.
ln ps = −
dT
=
Δ vapHm RT 2
(2)
⎛ d ln ps ⎞ Δ vapHm = ⎜ ⎟ ·RT 2 ⎝ dT ⎠
(3)
To solve eq 3, the measured ln(ps/Pa) and temperature data was regressed by using a quadratic polynomial equation24 with the correlation coefficient R2 shown in Table 5 for these compounds, and then eq 4 could be acquired. ln ps = −a + bT − cT 2
Δ vapH̅ m RT
+ C′
(6)
where R is the gas constant (= 8.314 J·mol−1·K−1) and C′ is a constant. The average molar enthalpy of vaporization ΔvapH̅ m was estimated by a linear relationship equation (eq 6) between the ln(ps/Pa) and 1/(T/K) within the range of the experimental temperature for these compounds. The value of ΔvapH̅ m was shown in Table 6 for these compounds, respectively. 3.3. Reliability Analysis of the Parameters. The values of the boiling point for camphene, pinane, and DHM were calculated to verify the reliability of regressed parameters, which was derived from the Antoine equation and presented in Table 7. A comparison of the calculated values of camphene, pinane, and DHM with the corresponding data reported in the literature gives a good agreement, and the relative deviations (RD) were less than 1.577 for these compounds. Furthermore, it was far from enough that the reported data in the literature could be applied in industrial production. Therefore, the
According to Clausius−Clapeyron equation for eq 2, the function relationship between ΔvapHm and temperature can be obtained by eq 3. d ln ps
(5)
(4)
Table 6. Parameter Values of ΔvapHm parameter camphene isobornyl acetate (±)-limonene pinane DHMOH DHM
a 23.2552 22.8118 22.8235 21.8040 49.4982 23.2099
b 0.1416 0.1173 0.1321 0.1301 0.2533 0.1393
c
m −4
1.4523·10 0.9823·10−4 1.2444·10−4 1.2408·10−4 2.6544·10−4 1.3714·10−4 497
1.1772 0.9752 1.0983 1.0816 2.1059 1.1581
ΔvapH̅ m/kJ·mol−1
n −3
2.3695·10 1.6334·10−3 2.0692·10−3 2.0632·10−3 4.4137·10−3 2.2804·10−3
41.59 50.30 44.48 43.08 59.85 43.69
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(11) Lecat, M. Nouveaux azéotropes binaires: 2nd list. Recl. Trav. Chim. Pays-Bas 1926, 45 (9), 620−627. (12) Smith, H. A.; Fuzek, J. F.; Meriwether, H. T. The Catalytic Hydrogenation of Terpenes. J. Am. Chem. Soc. 1949, 71 (11), 3765− 3769. (13) Stull, D. R. Vapor Pressure of Pure Substances Organic and Inorganic Compounds. Ind. Eng. Chem. 1947, 39 (4), 517−540. (14) Pines, H.; Olberg, R. C.; Ipatieff, V. N. Studies in the Terpene Series. XIV. Skeletal Isomerization and Hydrogen Transfer of Cyclic Olefins in the Presence of Alumina-Hydrogen Chloride and SilicaAlumina Catalysts. J. Am. Chem. Soc. 1952, 74 (19), 4872−4876. (15) Pines, H.; Hoffman, N. E.; Ipatieff, V. N. Studies in the Terpene Series. XX. The Thermal Isomerization of Pinane at Atmospheric Pressure. J. Am. Chem. Soc. 1954, 76 (17), 4412−4416. (16) Zhu, Y.; Chen, X.; Wang, L. Measurement and Correlation for Saturated Vapor Pressure of Pinane. J. Chem. Eng. Chin. Univ. 2003, 17 (5), 564−568 (in Chinese). (17) Yang, J.; Li, S.; Chen, Y. Measurement and Correlation for Saturated Vapor Pressure of Dihydromyrcene and Dihydromyrcenol. J. Chem. Eng. Chin. Univ. 2012, 5, 003 (in Chinese). (18) Eschenmoser, A.; Schinz, H. Zur Kenntnis der Sesquiterpene und Azulene. 91. Mitteilung. Zur Konstitution des Zingiberens. Helv. Chim. Acta 1950, 33 (1), 171−177. (19) Fischer, R.; Lardelli, G.; Jeger, O. Ü ber die Reduktion von α, βungesättigten Carbonylverbindungen nach Wolff-Kishner. 3. Mitteilung. Helv. Chim. Acta 1951, 34 (5), 1577−1585. (20) Wang, J.; Zheng, D.; Fan, L. Vapor Pressure Measurement for the Water + 1,3-Dimethylimidazolium Chloride System and 2, 2, 2Trifluoroethanol+ 1-Ethyl-3-methylimidazolium Tetrafluoroborate System. J. Chem. Eng. Data 2010, 55 (6), 2128−2132. (21) Yuan, X. J.; Xue, W. L.; Zeng, Z. X. Vapor pressure and enthalpy of vaporization of 2-amino-3-methylpyridine. J. Chem. Eng. Data 2007, 52 (6), 2431−2435. (22) Wagner, W.; Pruß, A. The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use. J. Phys. Chem. Ref. Data 2002, 31, 387. (23) Poling, B. E.; Prausnitz, J. M.; O’Connell, J. P. The Properties of Gases and Liquids; McGraw-Hill: New York. 2001. (24) Dong, H.; Wu, C.; Yang, X. Measurement and Correlation of Saturated Vapor Pressure of 2,4,6,8,10-Pentamethylcyclopentasiloxane by Means of an Inclined Ebulliometer. Thermochim. Acta 2009, 483 (1), 66−69.
regressed parameters obtained from the Antoine equation in the range of experimental data could satisfy the estimation requirements for chemical engineering design.
4. CONCLUSIONS Saturated vapor pressure is an inherent characteristic to the research of vapor−liquid equilibrium. However, this thermodynamic data are not always available in the early literature for α-pinene derivatives. This work expanded the range of measured vapor pressure data for camphene, isobornyl acetate, (±)-limonene, pinane, DHM, and DHMOH, respectively. The vapor pressure data were correlated with Antoine equation for each compound. The rmsd of vapor pressure for the above systems were 0.126 kPa, 0.193 kPa, 0.076 kPa, 0.100 kPa, 0.072 kPa, and 0.120 kPa. The function of ΔvapHm and temperature was obtained by the Clausius−Clapeyron equation, and the ΔvapH̅ m value was estimated for each compound. For reliability analysis, the calculated values by correlating the Antoine equation were in good agreement with reported values found in the literature. The Antoine parameters and the molar enthalpy of vaporization for these compounds provide fundamental data for engineering applications.
■
AUTHOR INFORMATION
Corresponding Author
*E-mail:
[email protected]. Tel.: +86 138 50100079. Funding
The authors would like to thank the National Natural Science Foundation of China (Grant No. 21106020) and the Natural Science Foundation of Fujian Province (Grant No. 2013J05026). Notes
The authors declare no competing financial interest.
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REFERENCES
(1) Monteiro, J. L. F.; Veloso, C. O. Catalytic Conversion of Terpenes into Fine Chemicals. Top. Catal. 2004, 27 (1−4), 169−180. (2) Comelli, N. A.; Ponzi, E. N.; Ponzi, M. I. Isomerization of α-pinene, Limonene, α-terpinene, and Terpinolene on Sulfated Zirconia. J. Am. Oil Chem. Soc. 2005, 82 (7), 531−535. (3) Chimal-Valencia, O.; Robau-Sánchez, A.; Collins-Martınez, V. Ion Exchange Resins as Catalyst for the Isomerization of α-pinene to Camphene. Bioresour. Technol. 2004, 93 (2), 119−123. (4) Dijs, I. J.; Van Ochten, H. L. F.; Van der Heijden, A. J. M. The Catalytic Performance of Sulphonated Cross-linked Polystyrene Beads in the Formation of Isobornyl Acetate. Appl. Catal. A, Gen. 2003, 241 (1), 185−203. (5) De Meireles, A. L. P.; Da Silva Rocha, K. A.; Kozhevnikov, I. V. Esterification of Camphene over Heterogeneous Heteropoly Acid Catalysts: Synthesis of Isobornyl Carboxylates. Appl. Catal. A, Gen. 2011, 409, 82−86. (6) Ritter, J. J. A New Camphor Synthesis. J. Am. Chem. Soc. 1933, 55 (8), 3322−3326. (7) Chouchi, D.; Gourgouillon, D.; Courel, M. The Influence of Phase Behavior on Reactions at Supercritical Conditions: The Hydrogenation of α-pinene. Ind. Eng. Chem. Res. 2001, 40 (12), 2551−2554. (8) Tanaka, J.; Katagiri, T.; Ozawa, K. The Thermal Isomerization of Pinane and its Products. Bull. Chem. Soc. Jpn. 1971, 44 (1), 130−132. (9) Liu, Y.; Zhou, Z.; Yang, G. A Study of Direct Hydration of Dihydromyrcene to Dihydromyrcenol Using Cation Exchange Resins as Catalyst. Int. J. Chem. Reactor Eng. 2010, 8 (1), No. 10.2202/15426580.2100. (10) Dong, H.; Wu, C.; Yang, X. Measurement and correlation of saturated vapor pressure of 2,4,6,8,10-pentamethylcyclopentasiloxane by means of an inclined ebulliometer. Thermochim. Acta 2009, 483, 66− 69. 498
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