Article pubs.acs.org/jced
Liquid−Liquid Equilibria for Ternary Systems: Methyl Butyl Ketone + Phenol + Water and Methyl Butyl Ketone + Hydroquinone + Water at 298.15 K and 323.15 K Yun Chen, Zhuo Wang,* and Libo Li School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, P. R.China ABSTRACT: Liquid−liquid equilibria (LLE) data for two ternary systems: methyl butyl ketone (MBK) + phenol + water and methyl butyl ketone + hydroquinone + water have been measured at 298.15 K and 323.15 K under atmospheric pressure. The reliability of experimental tie-line data was checked by Hand and Bachman equations. The distribution coefficient and selectivity were used to evaluate the extraction performance of methyl butyl ketone. In addition, NRTL (nonrandom two-liquid) and UNIQUAC (universal quasi-chemical activity coefficient) models were used to correlate experimental data, which yielded corresponding binary interaction parameters. Results from both models agree with each other well. NRTL model presents a stronger predictive power than UNIQUAC model.
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INTRODUCTION
data for MBK + phenol + water or MBK + hydroquinone + water have not been reported yet. To obtain reliable data for simulating phenol recovery from wastewater, LLE data for MBK + phenol + water and MBK + hydroquinone + water systems at temperatures of 298.15 K and 323.15 K under atmospheric pressure were measured. Since this study is focused on recovering diluted phenol and hydroquinone from industrial wastewater, corresponding LLE data are determined at low concentrations of phenol or hydroquinone. The nonrandom two-liquid (NRTL)10 and universal quasi-chemical activity coefficient (UNIQUAC)11 models were used to correlate LLE data to obtain binary interaction parameters between MBK, water, and phenol or hydroquinone.
Phenols are major pollutants in wastewater produced by many industrial processes, including petroleum refining, petrochemical manufacture, coking, coal gasification, and wood processing.1 Industrial phenolic wastewaters often have very complex compositions. Besides phenol, they also contain dihydric phenols with concentrations of hundreds or even thousands of milligrams per liter. These dihydric phenols are more difficult to extract due to their high affinity with water. In this work, we focus on two phenolic pollutants: phenol and hydroquinone. The removal of phenols from wastewater has been of great environmental interest over recent years. To treat wastewater with high phenol concentration (over 3000 mg·L−1), solvent extraction is a preferred method.2,3 There have been many solvents developed for extraction, such as methyl isobutyl ketone (MIBK), diisopropyl ether (DIPE),4 benzene, heavy benzene,5 ethyl acetate,6 isopropyl acetate, etc. Currently, methyl isobutyl ketone (MIBK) has been widely considered as an excellent extraction solvent due to its high efficacy to separate phenol from water. However, methyl isobutyl ketone (MIBK)’s distribution coefficients for dihydric phenols, such as hydroquinone, are low. In this article, methyl butyl ketone (MBK), with high distribution coefficients for both phenol and hydroquinone, was investigated as a new extraction solvent. Liquid−liquid equilibria (LLE) data are essential for extraction processes.7 Many researchers have studied LLE for various solvent−water−phenol ternary systems. Lei et al.3 reported LLE data for the 2-methoxy-2-methylpropane + phenol + water system. Yang et al.1,8 studied the extraction of phenol and hydroquinone with methyl isobutyl ketone. Martin et al.5,9 measured LLE data for aromatic hydrocarbon (toluene or ethylbenzene) + phenol + water systems and aliphatic hydrocarbon (heptane or octane) + phenols + water systems. However, LLE © XXXX American Chemical Society
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EXPERIMENTAL SECTION Chemicals. The suppliers and purity grades (expressed as mass fraction) of chemical reagents used in this work are shown in Table 1. The purity of these materials was confirmed by gas chromatography. Distilled water was used in all experiments. All chemicals in this study were used without further purification. Procedures. Experimental LLE data were measured with a 100 mL glass equilibrium cell consisting of a heating jacket to keep a constant temperature in the cell. The cell temperature was controlled by a thermostatic bath with a fluctuation of ±0.1 K. The ternary mixture was fed into the glass cell and was vigorously agitated with a magnetic stirrer for at least 2 h, then was left to stand for at least 20 h to reach phase equilibrium. After the above mixture formed two liquid phases, samples of both phases were collected by syringes and were analyzed by a Received: April 1, 2014 Accepted: August 25, 2014
A
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523.15 K and 543.15 K, respectively. Each sample was measured at least 3 times, and the standard deviation among the results is less than 0.2%. The average value was reported in this work.
Table 1. Suppliers and Purity Grade (Mass Fraction) of Chemical Reagents in Our Study component MBK phenol hydroquinone acetone n-octanol 2-butanone a
supplier Xiya Reagent Research Center GuangZhou Chemical Reagent Factory TianJin Kemiou Chemical Reagent Co., Ltd. BCR International Trading Co., Ltd. TianJin Kemiou Chemical Reagent Co., Ltd. Hengyang Kaixin Chemical Reagent Co., Ltd.
mass fraction
analysis method
0.99 0.995
GCa GCa
0.99
GCa
0.999
GCa
0.995
GCa
0.99
GCa
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RESULTS AND DISCUSSION LLE Experimental Data. The LLE data for ternary systems: MBK + phenol + water and MBK + hydroquinone + water, at 298.15 K and 323.15 K are listed in Tables 2 and 3, respectively. All concentrations are expressed in mass fraction. The phase behavior for studied systems was plotted in ternary diagrams as shown in Figure 1. To estimate the ability of MBK to separate phenol or hydroquinone from wastewater, the distribution coefficient (D) and the selectivity (S) are calculated as
Gas chromatograph.
D=
gas chromatograph (GC6820, Agilent Technologies) equipped with a flame ionization detector (FID) and a DB-5MS capillary column (30 m × 0.32 mm × 0.25 μm). The samples’ composition was determined by an internal standard method, where the internal standard was added into samples before GC analysis. Both the sample and the internal standard were weighed by an analytical balance (Shimadzu, AUW220D) with an accuracy of 0.1 mg. In the experiments, 2-butanone was used as an internal standard for MBK and n-octanol for phenol or hydroquinone. Water’s mass fraction was calculated by deducting all other components’ mass fraction from 1. The initial temperature of the GC’s oven was kept at 313.15 K for 2 min, then was increased at a rate of 30 K·min−1 to 463.15 K. Nitrogen was used as the carrier gas with a rate of 30 mL·min−1. The temperatures of the injector and the detector were set at
S=
w2O w2W
(1)
(w2 /w3)O (w2 /w3)W
(2)
where superscripts O and W mean organic solvent phase and aqueous phase, respectively, w2 is the mass fraction of phenol or hydroquinone, and w3 is that of water. The distribution coefficient and the selectivity for phenol and hydroquinone are also shown in Tables 2 and 3 (last 2 columns). The results (the maximum distribution coefficients for phenol and hydroquinone are 118.5 and 21.4) indicate that MBK is an efficient extraction solvent for both phenol and hydroquinone. Distribution coefficients were also shown in Figures 2 and 3 with comparison to MIBK:1,8 MBK
Table 2. Experimental LLE Data (Mass Fraction) for Ternary System MBK(1) + Phenol(2) + Water(3) at T = 298.15 K and 323.15 K and Pressure p = 0.1 MPaa organic phase T/K
w1
w2
w3
w1
w2
w3
D
S
298.15
0.8639 0.8803 0.8894 0.8989 0.9195 0.9217 0.9358 0.9432 0.9500 0.9559 0.9773 0.7004 0.7607 0.8042 0.8307 0.8488 0.8729 0.8965 0.9080 0.9211 0.9273 0.9352 0.9476 0.9709
0.0982 0.0836 0.0751 0.0665 0.0483 0.0474 0.0329 0.0279 0.0227 0.0180 0.0000 0.2408 0.1861 0.1511 0.1270 0.1123 0.0889 0.0655 0.0543 0.0436 0.0379 0.0313 0.0198 0.0000
0.0379 0.0361 0.0355 0.0346 0.0322 0.0314 0.0313 0.0289 0.0273 0.0261 0.0227 0.0588 0.0532 0.0447 0.0423 0.0389 0.0382 0.0380 0.0377 0.0353 0.0348 0.0335 0.0326 0.0291
0.01212 0.01224 0.01236 0.01241 0.01250 0.01252 0.01257 0.01260 0.01262 0.01264 0.01583 0.00787 0.00825 0.00877 0.00929 0.00948 0.00972 0.00975 0.00976 0.00978 0.00978 0.00980 0.00983 0.01093
0.00107 0.00089 0.00074 0.00067 0.00045 0.00040 0.00032 0.00026 0.00020 0.00016 0.00000 0.00507 0.00386 0.00283 0.00207 0.00165 0.00122 0.00098 0.00075 0.00054 0.00050 0.00039 0.00026 0.00000
0.9868 0.9869 0.9869 0.9869 0.9870 0.9871 0.9871 0.9871 0.9872 0.9872 0.9842 0.9871 0.9879 0.9884 0.9886 0.9889 0.9891 0.9893 0.9895 0.9897 0.9897 0.9898 0.9899 0.9891
91.78 93.93 101.5 99.25 107.3 118.5 102.8 107.3 113.5 112.5
2390 2568 2821 2831 3290 3725 3242 3665 4104 4255
47.50 48.21 53.39 61.35 68.06 72.87 66.84 72.40 80.74 75.80 80.26 76.15
797.3 895.3 1181 1434 1730 1887 1740 1900 2265 2156 2371 2312
323.15
a
aqueous phase
Standard uncertainties u are u(T) = 0.1 K, u(p) = 1 kPa, u(w) = 0.0019 for w > 0.1, u(w) = 0.0001 for w < 0.1, u(D) = 0.17, and u(S) = 13. B
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Figure 3. Distribution coefficient of hydroquinone versus its mass fraction in aqueous phase at T = 298.15 K and T = 323.15 K: ■, MBK + water system at T = 298.15 K; ▲, MBK + water system at T = 323.15 K; □, MIBK + water system at T = 298.15 K;1 △, MIBK + water system at T = 323.15K.1
Figure 1. LLE data for ternary systems: (a) {MBK + phenol + water} at T = 298.15 K, (b) {MBK + phenol + water} at T = 323.15 K, (c) {MBK + hydroquinone + water} at T = 298.15 K, and (d) {MBK + hydroquinone + water} at T = 323.15 K; ■, experimental data.
Figure 4. Hand plot for LLE data measured in this work: ■, MBK + phenol + water system at T = 298.15 K; ●, MBK + phenol + water system at T = 323.15 K; ▲, MBK + hydroquinone + water system at T = 298.15 K; ▼, MBK + hydroquinone + water system at T = 323.15 K.
The reliability of the experimental tie-line data was evaluated with Hand12 and Bachman13 equations, shown as eqs 3 and 4 respectively: ⎛ w ⎞W ⎛ w ⎞O ln⎜ 2 ⎟ = a1 + b1 ln⎜ 2 ⎟ ⎝ w1 ⎠ ⎝ w3 ⎠
(3)
⎛ wO ⎞ w1O = a 2 + b2⎜ 1W ⎟ ⎝ w3 ⎠
(4)
where a1, b1 and a2, b2 are parameters for Hand and Bachman equations, w1 is the mass fraction of MBK, w2 is the mass fraction of phenol or hydroquinone, and w3 is that of water. The straight lines calculated from Hand or Bachman equations are shown in Figures 4 and 5, respectively. The fitting parameters, together with corresponding linear correlation coefficient R2, are shown in Table 4. All R2 are greater than 0.99, indicating a good consistency of our LLE data.
Figure 2. Distribution coefficient of phenol versus its mass fraction in aqueous phase at T = 298.15 K and T = 323.15 K: ■, MBK + water system at T = 298.15 K; ▲, MBK + water system at T = 323.15 K; □, MIBK + water system at T = 298.15 K;5 △, MIBK + water system at T = 323.15 K.5
shows similar efficiency to MIBK in extracting phenol from water, but much higher efficiency in extracting hydroquinone. C
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Table 3. Experimental LLE Data (Mass Fraction) for Ternary System MBK(1) + Hydroquinone(2) + Water(3) at T = 298.15 K and 323.15 K and Pressure p = 0.1 MPaa organic phase w1
w2
w3
w1
w2
w3
D
S
298.15
0.7612 0.8124 0.8279 0.8520 0.8718 0.9069 0.9279 0.9402 0.9532 0.9605 0.9669 0.9773 0.7712 0.7963 0.8215 0.8410 0.8592 0.8986 0.9168 0.9286 0.9350 0.9442 0.9566 0.9593 0.9709
0.1988 0.1500 0.1367 0.1137 0.0960 0.0617 0.0410 0.0310 0.0193 0.0132 0.0070 0.0000 0.1695 0.1481 0.1282 0.1103 0.0924 0.0565 0.0417 0.0314 0.0255 0.0172 0.0069 0.0046 0.0000
0.0400 0.0376 0.0354 0.0343 0.0322 0.0314 0.0311 0.0288 0.0275 0.0263 0.0261 0.0227 0.0593 0.0556 0.0503 0.0487 0.0484 0.0449 0.0415 0.0400 0.0395 0.0386 0.0365 0.0361 0.0291
0.01182 0.01224 0.01232 0.01240 0.01249 0.01252 0.01258 0.01261 0.01262 0.01263 0.01284 0.01583 0.00951 0.00977 0.00989 0.01001 0.01002 0.01004 0.01010 0.01013 0.01024 0.01049 0.01055 0.01062 0.01094
0.01647 0.01218 0.01072 0.00826 0.00654 0.00415 0.00243 0.00171 0.00098 0.00063 0.00033 0.00000 0.02376 0.01916 0.01654 0.01399 0.01165 0.00698 0.00501 0.00337 0.00257 0.00171 0.00062 0.00034 0.00000
0.9717 0.9756 0.9770 0.9793 0.9810 0.9833 0.9850 0.9857 0.9864 0.9867 0.9868 0.9842 0.9667 0.9711 0.9736 0.9760 0.9783 0.9830 0.9849 0.9865 0.9872 0.9878 0.9888 0.9890 0.9891
12.07 12.32 12.75 13.77 14.68 14.87 16.87 18.13 19.69 20.95 21.21
293.2 319.5 351.9 393.0 447.2 465.6 534.4 620.5 706.4 786.1 802.0
7.134 7.730 7.751 7.884 7.931 8.095 8.323 9.318 9.922 10.06 11.13 13.53
116.3 135.0 150.0 158.0 160.3 177.2 197.5 229.8 248.0 257.4 301.5 370.7
323.15
a
aqueous phase
T/K
Standard uncertainties u are u(T) = 0.1 K, u(p) = 1 kPa, u(w) = 0.0019 for w > 0.1, u(w) = 0.0002 for w < 0.1, u(D) = 0.06, and u(S) = 3.2.
Gji = exp( −αjiτji)
where R is the ideal gas constant and T is the absolute temperature. For UNIQUAC model, the excess Gibbs energy is gE = RT
3
∑ xi ln i=1
ψi xi
3
+ 5 ∑ xiqi ln i=1
θi − ψi
⎞ ⎛ 3 ⎜ x q ln θτ ∑ i i ⎜∑ j ji⎟⎟ ⎠ ⎝ j=1 i=1 3
(6)
where
Figure 5. Bachman plot for LLE data measured in this work: □, MBK + phenol + water system at T = 298.15 K; ●, MBK + phenol + water system at T = 323.15 K; ▲, MBK + hydroquinone + water system at T = 298.15 K; ▼, MBK + hydroquinone + water system at T = 323.15 K.
τji =
n
∑ xi
n
n
∑l = 1 Glixl
θi =
xiqi 3 ∑i = 1 xiqi
⎛ uji − uii ⎞ ⎟ τji = exp⎜ − ⎝ RT ⎠
∑ j = 1 τjiGjixj
i=1
xiγi 3 ∑i = 1 xiγi
⎛ uij − ujj ⎞ ⎟ τij = exp⎜ − ⎝ RT ⎠
Data Correlation. The experimental LLE data were correlated using NRTL and UNIQUAC models. The equation for NRTL model is gE = RT
ψi =
Here qi and γi are UNIQUAC area and volume for species i; θi and ψi represent area fraction and segment fraction for species i; and τ is an adjustable parameter. The pure component structural parameters (γi and qi), taken from the literature,14,15 are shown in Table 5.
(5)
gji − gii RT D
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Table 4. Fitting Parameters in Hand or Bachman Equations Hand T/K
a1
Bachman R2
a2
b2
R2
0.009 0.005
0.9933 0.9947
0.9910 ± 0.0001 0.9980 ± 0.0001
−0.0036 ± 0.0001 −0.0078 ± 0.0001
0.9999 0.9999
0.001 0.001
0.9992 0.9975
1.050 ± 0.0001 1.093 ± 0.0001
−0.0618 ± 0.0001 −0.1002 ± 0.0001
0.9998 0.9999
b1
MBK (1) + Phenol (2) + Water (3) 298.15 0.9495 ± 0.0002 4.334 ± 323.15 0.9073 ± 0.0002 3.701 ± MBK (1) + Hydroquinone (2) + Water (3) 298.15 0.8931 ± 0.0001 2.251 ± 323.15 0.9119 ± 0.0001 1.823 ±
Table 5. Structural (Area and Volume) Parameters14,15 for the UNIQUAC Model component
r
q
water MBK phenol hydroquinone
0.9200 4.5967 3.5517 3.9156
1.4000 3.9560 2.6800 3.0080
The six binary interaction parameters in NRTL or UNIQUAC models were obtained by minimizing the objective function (OF) given in the following equation: 3
OF =
2
n
⎡
∑ ∑ ∑ ⎢⎢ i=1 j=1 k=1
(Tkexptl − Tkcalcd)2
⎣
σT 2
+
exptl calcd 2 ⎤ (wijk ) − wijk ⎥ 2 ⎥⎦ σw
(7) exptl
exptl
where n is the number of tie-lines, w and T are experimental mass fraction and temperature, and wcalcd and Tcalcd are calculated mass fraction and temperature. Subscripts i, j, and k refer to the components, the phases, and the tie-lines, respectively. σT and σw denote standard deviations for experimental temperatures and mass fractions. The binary interaction parameters for our studied system calculated from NRTL or UNIQUAC models are listed in Table 6. The root-mean-square-deviation (RMSD), used to check the agreement between the experimental data and the calculated data, was defined as ⎡ ∑3 ∑2 ∑n (w exptl − w calcd)2 ⎤1/2 ijk ijk i=1 j=1 k=1 ⎥ RMSD(%) = 100 × ⎢ ⎢ ⎥ 6 n ⎣ ⎦
Figure 6. Mass fraction of phenol in the organic phase versus that in aqueous phase in system MBK + phenol + water: ■, experimental data at 298.15 K; ▲, experimental data at 323.15 K; , calculated data from NRTL model; ···, calculated data from UNIQUAC model.
The RMSD values for NRTL or UNIQUAC models are shown in Table 6, which show good representation of the tieline data for all studied systems. According to these RMSD values, the NRTL model is more accurate than the UNIQUAC model. The experimental data and calculated data (from NRTL or UNIQUAC models) for phenol and hydroquinone at 298.15 K or 313.15 K are shown in Figures 6 and 7. These figures show
(8)
Table 6. Binary Interaction Parameters Calculated from NRTL and UNIQUAC Model for Ternary Systems: MBK(1) + Phenol(2) + Water (3) and MBK(1) + Hydroquinone(2) + Water(3)a components T/K
i−j
UNIQUAC bij/K
MBK (1) + Phenol (2) + Water (3) 298.15 1−2 2004.53 1−3 −384.24 2−3 152.61 323.15 1−2 4128.87 1−3 −345.23 2−3 98.58 MBK (1) + Hydroquinone (2) + Water (3) 298.15 1−2 −212.65 1−3 −371.88 2−3 −346.78 323.15 1−2 −210.57 1−3 −301.87 2−3 131.99 a
NRTL
bji/K
RMSD/%
bij/K
bji/K
αij
RMSD/%
−121.71 −121.50 1308.19 −269.32 −169.33 3436.99
0.080
−1046.79 1381.72 −667.22 −1500.30 1443.21 −533.24
6562.47 −1919.56 1828.78 2812.45 −1971.89 1324.22
0.3 0.2 0.2 0.3 0.2 0.2
0.089
−1004.54 1372.53 −568.43 367.87 1395.57 −518.37
5498.25 −1914.99 1142.65 −491.82 −1932.37 1459.00
0.3 0.2 0.2 0.3 0.2 0.2
240.71 −124.27 174.16 244.53 −184.79 −115.61
0.265
0.205
0.176
0.260
0.186
0.168
The NRTL and UNIQUAC model parameters (bij, bji) are defined as bij = (gij − gii)/R and bij = (uij − uii)/R, respectively. E
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(2) González-Muñoz, M. J.; Luque, S.; Á lvarez, J. R.; Coca, J. Recovery of Phenol from Aqueous Solutions Using Hollow Fibre Contactors. J. Membr. Sci. 2003, 213, 181−193. (3) Lei, Y.; Chen, Y.; Li, X.; Qian, Y.; Yang, S.; Yang, C. Liquid− Liquid Equilibria for the Ternary System 2-Methoxy-2-methylpropane + Phenol + Water. J. Chem. Eng. Data 2013, 58, 1874−1878. (4) Mikhaleva, M. S.; Egutkin, N. L. About the Extraction Mechanism of Phenol from Water Solutions by Diisopropyl Ether. Bashk. Khim. Zh. 2008, 15 (2), 168−170. (5) Martin, A.; Klauck, M.; Taubert, K.; Precht, A.; Meinhardt, R.; Schmelzer, J. Liquid−Liquid Equilibria in Ternary Systems of Aromatic Hydrocarbons (Toluene or Ethylbenzene) + Phenols + Water. J. Chem. Eng. Data 2010, 56, 733−740. (6) Yur’ev, Y. L.; Kiprianov, A. I.; Yudkevich, Y. D. Isolation of Phenols from a Soluble Resin by Acetate Solvents. Anal. Chem. 1974, 46 (4), 482−5. (7) Mohammad Doulabi, F. S.; Mohsen-Nia, M. Ternary Liquid− Liquid Equilibria for Systems of (Sulfolane + Toluene or Chloronaphthalene + Octane). J. Chem. Eng. Data 2006, 51, 1431− 1435. (8) Yang, C.; Qian, Y.; Zhang, L.; Jiang, Y. Measurement and Correlation of Liquid−Liquid Equilibrium Data for Methyl Isobutyl Ketone−Water−Phenol Ternary System. J. Chem. Ind. Eng. 2007, 58, 805−809. (9) Martin, A.; Klauck, M.; Grenner, A.; Meinhardt, R.; Martin, D.; Schmelzer, J. Liquid−Liquid(−Liquid) Equilibria in Ternary Systems of Aliphatic Hydrocarbons (Heptane or Octane) + Phenols + Water. J. Chem. Eng. Data 2010, 56, 741−749. (10) Renon, H.; Prausnitz, J. M. Local Compositions in Thermodynamic Excess Functions for Liquid Mixtures. AIChE J. 1968, 14, 135−144. (11) Abrams, D. S.; Prausnitz, J. M. Statistical Thermodynamics of Liquid Mixtures: A New Expression for the Excess Gibbs Energy of Partly or Completely Miscible Systems. AIChE J. 1975, 21, 116−128. (12) Hand, D. Dineric Distribution. J. Phys. Chem. 1929, 34, 1961− 2000. (13) Bachman, I. Tie Lines in Ternary Liquid Systems. Ind. Eng. Chem., Anal. Ed. 1940, 12, 38−39. (14) Mafra, M. R.; Krähenbühl, M. A. Liquid−Liquid Equilibrium of (Water + Acetone) with Cumene or α-Methylstyrene or Phenol at Temperatures of (323.15 and 333.15) K. J. Chem. Eng. Data 2006, 51, 753−756. (15) Magnussen, T.; Rasmussen, P.; Fredenslund, A. UNIFAC Parameter Table for Prediction of Liquid−Liquid Equilibria. Ind. Eng. Chem. Process Des. Dev. 1981, 20, 331−339.
Figure 7. Mass fraction of hydroquinone in the organic phase versus that in aqueous phase in system MBK + hydroquinone + water: ■, experimental data at 298.15 K; ▲, experimental data at 323.15 K; , calculated data from NRTL model; ···, calculated data from UNIQUAC model.
that the calculated data are in good agreement with experimental data, which indicates both NRTL and UNIQUAC models are suitable for simulating phenol or hydroquinone extraction.
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CONCLUSIONS LLE data for ternary systems, methyl butyl ketone + phenol + water and methyl butyl ketone + hydroquinone + water, were measured at 298.15 K and 323.15 K under atmospheric pressure. The distribution coefficients indicate that methyl butyl ketone is an efficient solvent to remove both phenol and hydroquinone from water. In comparison with another excellent extraction solvent MIBK, which was widely used in the industry, MBK shows similar efficacy to MIBK to extract phenol from water, but much higher efficacy to extract hydroquinone. Experimental results were correlated using both NRTL and UNIQUAC models, which indicates NRTL activity coefficient model is more accurate for LLE calculation in our studies. The binary interaction parameters calculated from both models can be used to design or optimize extraction or separation processes for phenols.
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AUTHOR INFORMATION
Corresponding Author
*(Z.W.) Tel:+8613798005381. E-mail:
[email protected]. edu.cn. Funding
Financial support from Project of the Science & Technology New Star of Pearl River in Guangzhou (2011J2200056), the Fundamental Research Funds for the Central Universities, SCUT (2014ZZ0057), and National Science Foundation of Chin a(20906028) are gratefully acknowledged. Notes
The authors declare no competing financial interest.
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REFERENCES
(1) Yang, C.; Jiang, Y.; Zhang, L.; Qian, Y. Liquid−Liquid Equilibria for the Ternary System Methyl Isobutyl Ketone + Water + Hydroquinone. J. Chem. Eng. Data 2006, 51, 2107−2109. F
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