This document presents experimental liquid-liquid equilibrium data for ternary mixtures of 1-butylpyridinium nitrate ionic liquid, various alkanes (heptane, octane, decane), and either ethylbenzene or p-xylene at 298.15 K and 89 kPa. The data includes mole fraction measurements of each phase and calculations of distribution ratios and separation factors. Six different ternary systems were studied and the results suggest p-xylene can be separated more easily from alkanes than ethylbenzene.

1. Liquid−Liquid Equilibria Data for Ethylbenzene or p‑Xylene with
Alkane and 1‑Butylpyridinium Nitrate Ionic Liquid at 298.15 K
Mobin Enayati, Babak Mokhtarani,* Ali Sharifi, Sanam Anvari, and Mojtaba Mirzaei
Chemistry and Chemical Engineering Research Center of Iran, P.O. Box 14335-186, Tehran, Iran
*S Supporting Information
ABSTRACT: Liquid−liquid equilibrium data (LLE) for the mixtures of ionic
liquid (IL) + alkane + aromatic {1-butylpyridinium nitrate, [BPy][NO3] (1) +
heptane, octane, or decane (2) + ethylbenzene (3)} and {[BPy][NO3] (1) +
heptane, octane, or decane (2) + p-xylene (3)} at T = 298.15 K and P =
89 Kpa were measured. The degree of reliability of the experimental LLE
data was examined by using the Othmer-Tobias and Hand correlation.
For the six studied ternary mixtures, the separation factor and distribution
ratio of aromatic hydrocarbons derived from LLE data and were applied to
determine if [BPy][NO3] can be used as dearomatization solvent. The
separation of aromatic compounds with similar molecular weight (ethyl-
benzene and p-xylene) from alkanes demonstrates that p-xylene can be
separated more easily from alkanes. The triangular phase diagrams for all studied systems were sketched, and the tie lines were
compared with the NRTL model.
1. INTRODUCTION
Liquid−liquid extraction is the separation process frequently
used for separation of aromatics from alkanes. Sulfolane,
N-methylpyrrolidone (NMP), N-formylmorpholine (NFM), and
ethylene glycol are the common solvents for this process.1−8
However, these volatile organic compounds (VOCs) are gen-
erally flammable, toxic, and crucial to be recycled, so it is
necessary to design new solvents with an impressive efficiency
and less harmful for the environment. Ionic liquids (ILs) may
be an alternative for these solvents in the dearomatization of
naphtha, fuel jets, and kerosene in liquid−liquid extraction.9−11
The exceptional properties of ILs are negligible vapor pressure,
nonflammability in ambient temperature and pressure, recy-
clability, and high thermal and chemical stability. Extraction of
aromatic compound with ILs may have less steps and operating
cost in an industrial process.12
Separation of alkane from the aromatic compound is a
challenging problem and application of ILs for this process have
been studied by many researchers.13−32
Most of the research in
this context were published with imidazolium-based ILs but
with pyridinium-based ILs only few works were found in the
literature.29−33
Besides, among the research conducted in the
extraction of the light aromatic (benzene, toluene, ethyl-
benzene, and xylenes) from paraffinic hydrocarbons with ILs,
experimental data on extraction of aromatic hydrocarbons with
the same molecular weight (ethylbenzene and p-xylene) from
alkanes are scarce.34,35
Because of this, the liquid−liquid
equilibrium data (LLE) for ethylbenzene or p-xylene with
alkane- and pyridinium-based ILs is indispensable for dearoma-
tization process. This research is a continuation of our ongo-
ing research on the separation of aromatic compounds from
alkane using the pyridinium or imidazolium based ILs.25,35−37
1-Butylpyridinium nitrate ([BPy][NO3]) was used for the extrac-
tion of toluene or benzene from paraffinic hydrocarbons in our
previous works.36,37
Because of the high potential of this IL,
[BPy][NO3] was chosen for separation of aromatic hydro-
carbons with an identical molecular weight (ethylbenzene and
p-xylene) from alkane. For this objective, the LLE data of
{[BPy][NO3] (1) + alkane (C7 or C8 or C10) (2) + ethylbenzene
or p-xylene (3)} were determined at 298.15 K and 89 kPa. On
the basis of the experimental data, the aromatic distribution
ratio (β) and the separation factor (α3,2) were estimated and
compared with data from other ILs reported in literature. The
reliability of the experimental data was tested with the Othmer-
Tobias38
and Hand39
correlation. Finally, the experimental data
were correlated with the NRTL thermodynamic model.40
2. MATERIALS AND METHODS
Heptane, octane, decane, ethylbenzene, and 1,4-dimethylben-
zene (p-xylene) were provided from Merck Company. The
analysis method and the mass fraction of water in chemicals are
given in Table 1.
[BPy][NO3] was produced and purified in the organic chem-
istry laboratory in CCERCI (Iran, Tehran). The IL was syn-
thesized from 1-butylpyridinium bromide ([BPy][Br]). The
synthesize method of [BPy][Br] is reported in the literature.41
According to this method, pyridine and 1-bromobutane are
reacted with each other to produce [BPy][Br] and from the
reaction of [BPy][Br] with silver nitrate, [BPy][NO3] is
obtained.42
NMR spectroscopy was used in order to check the
Received: October 15, 2016
Accepted: February 14, 2017
Published: February 22, 2017
Article
pubs.acs.org/jced
© 2017 American Chemical Society 1068 DOI: 10.1021/acs.jced.6b00881
J. Chem. Eng. Data 2017, 62, 1068−1075

2. structure and purity of the IL and the spectrum is represented
in the Supporting Information (Figure S1). In order to remove
impurities and moisture, the ILs were dried, degassed, and kept
under vacuum for 1 day at 343 K temperature. The mass frac-
tion of the water of the chemicals was measured using 684 Karl
Fischer coulometer and shown in Table 1.
The equipment and experimental method are similar to our
previous studies.36,37
To determinate the LLE data, the mix-
tures of each of the studied systems{[BPy][NO3] (1) + heptane,
or octane, or decane (2) + ethylbenzene (3)} and {[BPy][NO3]
(1) + heptane, or octane, or decane (2) + p-xylene (3)} were
prepared in glass vials with 15 cm3
volume. The mass of each
component was weighed with the OHAUS model laboratory
balance and the measurement precision was ±10−4
g. The glass
vials were closed with caps and septum because the mixture is
volatile. The composition of the mixture in the glass vial was
selected in the region that the two liquid phases were formed.
The mixtures were shaken with an IKA model shaker for 5 h at
300 rpm. Then, the mixtures were inserted into a water bath
(Huber, K20-NR) for 12 h at 298.15 K in order for the two
liquid phases to be separated completely. The precise tem-
perature measurement of the water bath was ±0.1 K. After 12 h,
the composition of each of the phases was measured. The
upper and lower phase is rich from alkane IL, and their
compositions were measured by gas chromatography (Varian,
cp 3800). The detector of gas chromatography was flame
Table 1. Water Content, Purities, Analysis Method, and Suppliers of the Chemicals
chemical name CAS No. supplier mass fraction purity water content (ppm) analysis method
ethylbenzene 100-41-4 Merck 0.994 196 GC
1,4 dimethylbenzene (p-xylene) 106-42-3 Merck 0.99 105 GC
heptane 142-82-5 Merck 0.995 121 GC
octane 111-65-9 Merck 0.992 204 GC
decane 124-18-5 Merck 0.992 88 GC
[BPy][NO3] synthesized in our lab >0.98 1011 NMR, Karl Fischer titration
Table 2. Experimental LLE Data in Mole Fraction, Calculated Distribution Ratio (β), and Separation Factor Values (α3,2) for
Ternary Systems of {[BPy][NO3] (1) + Alkane (2) + Ethylbenzene (3)} at T = 298.15 K and P = 89 KPaa
feed alkane rich phase IL rich phase
x1 x2 x3 x2
I
x3
I
x2
II
x3
II
β α3,2
[BPy][NO3] (1) + Heptane (2) + Ethylbenzene (3)
0.300 0.665 0.035 0.958 0.042 0.011 0.021 0.49 42.93
0.300 0.630 0.070 0.913 0.087 0.010 0.033 0.38 34.11
0.300 0.560 0.139 0.820 0.180 0.009 0.053 0.29 26.39
0.301 0.488 0.211 0.719 0.281 0.008 0.066 0.24 21.44
0.300 0.419 0.281 0.621 0.379 0.007 0.079 0.21 17.69
0.301 0.350 0.349 0.521 0.479 0.007 0.090 0.19 14.42
0.300 0.280 0.420 0.419 0.581 0.007 0.107 0.18 11.85
0.301 0.210 0.489 0.319 0.681 0.006 0.127 0.19 9.47
0.300 0.140 0.560 0.214 0.786 0.006 0.146 0.19 6.99
0.300 0.071 0.629 0.109 0.891 0.005 0.176 0.20 4.34
[BPy][NO3] (1) + Octane (2) + Ethylbenzene (3)
0.300 0.665 0.034 0.961 0.039 0.011 0.024 0.60 53.85
0.301 0.629 0.070 0.915 0.085 0.009 0.038 0.45 45.66
0.301 0.559 0.140 0.824 0.176 0.008 0.063 0.36 38.73
0.301 0.490 0.209 0.728 0.272 0.007 0.082 0.30 31.90
0.300 0.419 0.280 0.628 0.372 0.006 0.099 0.27 25.87
0.300 0.350 0.350 0.528 0.472 0.006 0.116 0.25 20.97
0.300 0.280 0.420 0.428 0.572 0.006 0.137 0.24 16.72
0.300 0.210 0.490 0.326 0.674 0.006 0.162 0.24 13.51
0.300 0.141 0.559 0.220 0.780 0.005 0.186 0.24 9.82
0.301 0.071 0.629 0.113 0.887 0.005 0.227 0.26 6.07
[BPy][NO3] (1) + Decane (2) + Ethylbenzene (3)
0.301 0.664 0.035 0.961 0.039 0.009 0.027 0.69 70.85
0.300 0.629 0.070 0.918 0.082 0.008 0.045 0.54 60.15
0.300 0.560 0.139 0.830 0.170 0.007 0.075 0.44 52.24
0.300 0.489 0.211 0.733 0.267 0.006 0.100 0.37 44.29
0.300 0.420 0.280 0.638 0.362 0.006 0.122 0.34 37.23
0.301 0.351 0.349 0.541 0.459 0.005 0.147 0.32 31.88
0.300 0.279 0.420 0.438 0.562 0.005 0.177 0.31 26.49
0.300 0.211 0.489 0.337 0.663 0.005 0.205 0.31 21.01
0.300 0.141 0.559 0.232 0.768 0.005 0.243 0.32 15.68
0.300 0.071 0.629 0.121 0.879 0.004 0.295 0.34 11.10
a
Standard uncertainties (u) are u(xi) = 0.001, u(T) = 0.1 K, u(P) = 1 kPa.
Journal of Chemical & Engineering Data Article
DOI: 10.1021/acs.jced.6b00881
J. Chem. Eng. Data 2017, 62, 1068−1075
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3. ionization detector (FID) type and the capillary column
(CP-SIL 5CB, Chrompack, 25 m × 0.3 mm × 1.2 μm) was used
for analysis. The upper phases contain alkane and aromatic and
no IL exists in this phase. This was improved by the NMR
analysis. However, the lower phase contains IL, alkane, and
aromatic. The lower phase samples were diluted with acetone
and injected into the GC. The IL may damage the column and
should be collected before injection. Therefore, a liner of filled
glass wool was inserted before the injector. The experimental
standard uncertainties for calculation of phase compositions
of alkane and IL rich phase were less than 1 × 10−3
in mole
fraction.
3. EXPERIMENTAL RESULTS
The experimental results for the system of {[BPy][NO3] (1) +
heptane, octane, or decane (2) + ethylbenzene (3)}and {[BPy]-
[NO3] (1) + heptane, octane, or decane (2) + p-xylene (3)} at
298.15 and 89 Kpa are reported in Tables 2 and 3. According to
these tables, the mole fractions of IL in the feed were selected
to 0.3 based on preliminary experiments. Higher mole fraction
of IL in the feed resulted in the consumption of more IL and is
not economical. Also, at higher mole fraction of IL the volume
of IL-rich phase is more than the volume of alkane-rich phase.
At lower amounts of IL, the volumes of IL-rich phase are
reduced and the extraction of aromatic is decreased. However,
at 0.3 mole fraction of IL, the volume ratio of IL-rich phase
to alkane-rich phase is equal. The experimental results for each
system in mole fraction are represented in Figure 1. Accord-
ing to Figure 1, the solubility of aromatic (ethylbenzene or
p-xylene) is more than alkane in the studied IL. This implies
[BPy][NO3] is suitable solvent for the separation of ethyl-
benzene and p-xylene from alkane. In addition, comparing the
aromatic (ethylbenzene and p-xylene) with similar molecular
weight in this work, it is worth noting that the solubility of
p-xylene is more than ethylbenzene in [BPy][NO3]. Besides, the
comparison of the studied systems shows that the miscibility
areas are increasing with enlargement the alkane chain length.
The experimental data was correlated with Othmer-Tobias38
and Hand39
equations
−
= +
−⎛
⎝
⎜
⎞
⎠
⎟
⎛
⎝
⎜
⎞
⎠
⎟
w
w
a b
w
w
ln
1
ln
12
I
2
I
1
II
1
II
(1)
= +
⎛
⎝
⎜
⎞
⎠
⎟
⎛
⎝
⎜
⎞
⎠
⎟
w
w
c d
w
w
ln ln3
I
2
I
3
II
1
II
(2)
Table 3. Experimental LLE Data in Mole Fraction, Calculated Distribution Ratio (β) and Separation Factor Values (α3,2) for
Ternary Systems of {[BPy][NO3] (1) + Alkane (2) + p-Xylene (3)} at T = 298.15 K and P = 89 KPaa
feed alkane rich phase IL rich phase
x1 x2 x3 x2
I
x3
I
x2
II
x3
II
β α3,2
[BPy][NO3] (1) + Heptane (2) + p-Xylene (3)
0.301 0.664 0.035 0.959 0.041 0.011 0.024 0.59 50.90
0.301 0.629 0.070 0.915 0.085 0.010 0.039 0.46 42.98
0.301 0.559 0.140 0.823 0.177 0.008 0.063 0.36 36.18
0.301 0.489 0.210 0.727 0.273 0.007 0.081 0.30 31.06
0.301 0.419 0.280 0.628 0.372 0.006 0.098 0.26 26.08
0.301 0.349 0.350 0.528 0.472 0.006 0.115 0.24 22.82
0.300 0.280 0.420 0.427 0.573 0.005 0.134 0.23 18.14
0.300 0.211 0.489 0.326 0.674 0.006 0.156 0.23 13.53
0.300 0.140 0.559 0.219 0.781 0.006 0.184 0.24 9.31
0.300 0.070 0.630 0.111 0.889 0.005 0.219 0.25 5.55
[BPy][NO3] (1) + Octane (2) + p-Xylene (3)
0.300 0.664 0.036 0.961 0.039 0.011 0.027 0.68 62.04
0.300 0.630 0.070 0.918 0.082 0.010 0.044 0.54 50.88
0.301 0.559 0.141 0.827 0.173 0.008 0.075 0.43 43.50
0.301 0.490 0.209 0.734 0.266 0.007 0.095 0.36 36.08
0.300 0.419 0.281 0.634 0.366 0.007 0.116 0.32 29.39
0.300 0.350 0.350 0.535 0.465 0.006 0.136 0.29 24.57
0.300 0.280 0.419 0.435 0.565 0.006 0.160 0.28 19.57
0.300 0.210 0.489 0.332 0.668 0.006 0.188 0.28 15.10
0.301 0.141 0.558 0.227 0.773 0.005 0.217 0.28 11.62
0.301 0.070 0.628 0.116 0.884 0.005 0.266 0.30 7.26
[BPy][NO3] (1) + Decane (2) + p-Xylene (3)
0.301 0.664 0.035 0.962 0.038 0.009 0.029 0.77 79.74
0.300 0.629 0.070 0.920 0.080 0.009 0.050 0.63 68.08
0.300 0.560 0.139 0.834 0.166 0.007 0.086 0.52 58.63
0.300 0.489 0.211 0.738 0.262 0.006 0.111 0.43 49.07
0.300 0.420 0.280 0.644 0.356 0.006 0.139 0.39 41.85
0.301 0.351 0.349 0.547 0.453 0.006 0.166 0.37 34.35
0.300 0.279 0.420 0.446 0.554 0.006 0.200 0.36 28.38
0.300 0.211 0.489 0.345 0.655 0.005 0.236 0.36 23.02
0.300 0.141 0.559 0.240 0.760 0.005 0.282 0.37 18.12
0.300 0.071 0.629 0.126 0.874 0.004 0.332 0.38 13.01
a
Standard uncertainties (u) are u(xi) = 0.001, u(T) = 0.1 K, u(P) = 1 kPa.
Journal of Chemical & Engineering Data Article
DOI: 10.1021/acs.jced.6b00881
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4. where w refers to the mass fraction of component. The super-
scripts I and II represent the alkane and IL rich phases. The
subscripts 1, 2, and 3 denote the IL, alkane, and aromatic
component, respectively. The constants a, b, c, and d are fitted
parameters that are reported in Tables S1 and S2. The values of
the regression coefficients (R2
) for both equations are calcu-
lated in these tables and are more than 0.98, which indicates the
reliability of the experimental LLE data.
The capacity of [BPy][NO3] as a new solvent for separation
process was evaluated using the separation factor (α3,2) and
Figure 1. Experimental (the solid lines and full points) and calculated data of the NRTL model (dashed line and empty points) for ternary systems
containing {[BPy][NO3] (1) + alkane (2) + ethylbenzene (3)} at T = 298.15 K for (a) heptane, (b) octane, (c) decane; and {[BPy][NO3] (1) +
alkane (2) + p-xylene (3)} at T = 298.15 K for (d) heptane, (e) octane, (f) decane.
Journal of Chemical & Engineering Data Article
DOI: 10.1021/acs.jced.6b00881
J. Chem. Eng. Data 2017, 62, 1068−1075
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5. solute distribution ratio (β), which were calculated from the
experimental LLE data according to the following equations
α =
x x
x x
3,2
3
II
2
I
3
I
2
II
(3)
β =
x
x
3
II
3
I
(4)
where x refers to the mole fraction of aromatic (3) or alkane
(2) and the superscripts I and II represent the alkane- and
IL-rich phases. The lower solute distribution ratio value indi-
cates to a higher extractant need for extraction operation and
the higher separation factor reduces the number of stages for
extraction process and therefore lowers operating costs and
uses smaller apparatus.43
Tables 2 and 3 shows that the separa-
tion factor values are more than one which indicated the
studied IL is an appropriate solvent for separation of aromatic
from alkane.
The variations of separation factor and distribution ratio with
the mole fraction of aromatic hydrocarbons in alkane rich phase
for the ternary systems {[BPy][NO3] (1) + heptane, or octane,
or decane (2) + ethylbenzene (3)} are plotted in Figure 2 and
Figure S2. As the figures show, the separation of ethylbenzene
from decane is easier than other alkanes. The separation factor
and solute distribution ratio values increase with the enlarge-
ment of the alkane chain length. This behavior is the same as
our previous research for extraction of aromatic hydrocarbons
from alkanes using other ILs.36,37
The separation factors of aromatic hydrocarbons for [BPy]-
[NO3] in this study and sulfolane44
and other types of the IL with
imidazolium cation for the mixture of {IL or sulfolane (1) +
heptane (2) + aromatic (3)} are compared in Figure 3. The
data for this figure is reported in Table S3 of Supporting
Information. It is worth mentioning that the separation
factor reduces as the mole fraction of aromatic hydrocar-
bons in the alkane rich phase increases. As it can be seen in
this figure for [BPy][NO3], the separation factor of aromatic
hydrocarbons are changed according to this order (Sbenzene >
Sp‑xylene > Sethylbenzene). This result is observed for other types of
ILs in the literature. Moreover, comparison between ethyl-
benzene and p-xylene with similar molecular weight indicates
that the separation factor values of p-xylene are higher than
ethylbenzene in [BPy][NO3]. According to this figure, the
separation factor values for the [BPy][NO3] are greater than
sulfolane, which indicates [BPy][NO3] is a suitable replace-
ment for this solvent; therefore, the ILs can be recovered and
reused many times. Further, [BPy][NO3] and [Bmim][NO3]35
with the same anion have been compared and it was found that
the separation factor values derived from pyridinium-based ILs
may be more than the imidazolium-based ILs.
4. THERMODYNAMIC MODELING
The NRTL model40
was used for fitting the experimental LLE
data of the studied systems in this research. The activity coeffi-
cient in the NRTL model is expressed as follows
∑γ
τ
τ
τ
=
∑
∑
+
∑
−
∑
∑
=
= = =
=
=
⎛
⎝
⎜⎜
⎞
⎠
⎟
⎟
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟
xG
x G
xG
x G
x G
x G
ln i
j
n
ji j ji
k
n
k ki j
n
j ij
k
n
k kj
ij
m
n
mi m mi
k
n
k kj
1
1 1 1
1
1
(5)
Where
α τ= − ·G exp( )ij ij (6)
τ =
Δg
RT
ij
ij
(7)
where x stands for mole fraction, T refers to absolute tem-
perature, and R is the gas constant. The nonrandomness
parameter (α) is fixed to 0.3 during calculations, and Δgij is the
parameter of energy
Δ = −g g gij ij jj (8)
Figure 2. Separation factor versus the mole fraction of ethylbenzene in
alkane rich phase for the ternary systems of {[BPy][NO3] (1) + alkane
(2) + ethylbenzene (3)} at T = 298.15 K: (●) heptane, (Δ) octane,
(■) decane.
Figure 3. Scheme of the separation factor of the experimental and
literature data versus mole fraction of aromatic in the alkane-rich phase
for the ternary systems of {solvent (1) + heptane (2) + aromatic (3)}
at T = 298.15 K; ■, [BPy][NO3] (1) + heptane (2) + ethylbenzene
(3) (this work); ▲, [BPy][NO3] (1) + heptane (2) + p-xylene (3)
(this work); ●, [BPy][NO3] (1) + heptane (2) + benzene (3);37
○,
[Bmim][NO3] (1) + heptane (2) + p-xylene (3);35
Δ, sulfolane (1) +
heptane (2) + p-xylene (3)44
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6. The difference of experimental and calculated mole fractions for
each component of the ternary system is selected as objective
function as follow and the function should be minimized
∑ ∑ ∑=
−− ⎛
⎝
⎜
⎜
⎞
⎠
⎟
⎟F
x x
xi
m
j
n
k
ijk ijk
ijk
1 2 exp cal
exp
2
(9)
Here m refers to the number of tie lines, n refers to the number
of components in the mixture, k defines the number of phases,
and x is mole fraction values. The root-mean-square deviation
(rmsd, in %) is calculated as follow:
=
∑ ∑ ∑
×
− −⎡
⎣
⎢
⎢
⎢
⎢
⎛
⎝
⎜
⎞
⎠
⎟
⎤
⎦
⎥
⎥
⎥
⎥
mn
rmsd
2
100
i
m
j
n
k
x x
x
1 2
2 1/2
ijk ijk
ijk
exp cal
exp
(10)
where n denotes the number of the components and m is the
number of the tie lines. The LLE data is correlated with the
Microsoft Excel program (Solver). The rmsd values and the
binary energy parameters are calculated and presented in
Table 4. As can be observed, the small rmsd values are shown in
Table 4 and the NRTL model can correlate the LLE data with a
good validity.
5. CONCLUSION
The experimental data for systems of [BPy][NO3] + alkane +
ethylbenzene or p-xylene are reported for the first time. These
experimental data are essential for the separation of aromatic
compounds from alkane. The separation of aromatic compounds
with similar molecular weight (ethylbenzene and p-xylene) from
alkanes (heptane, octane, and decane) was performed with
pyridinium-based IL as a new solvent at T = 298.15 K and P =
89 Kpa. Using [BPy][NO3] as the new solvent for extraction of
aromatic from alkanes was studied by calculating the separation
factor and distribution ratio of aromatic hydrocarbons
parameters. The separation factor values of [BPy][NO3] were
higher than the unity on the whole range of compositions and
this means it can be a choice for replacement of traditional
organic solvents. However, more experimental data with other
types of ILs are needed for these systems. The alkane chain
length enlargement leads to an increase of the separation factor
and distribution ratio of aromatic hydrocarbons parameters. In
addition, the experimental data on extraction of aromatic
hydrocarbons with the same molecular weight (ethylbenzene
and p-xylene) indicated that p-xylene can be extracted from
alkanes easily. Finally, the NRTL thermodynamic model was
successfully applied to correlate the LLE data.
■ ASSOCIATED CONTENT
*S Supporting Information
The Supporting Information is available free of charge on the
ACS Publications website at DOI: 10.1021/acs.jced.6b00881.
The data for Figure 3 is reported in Table S3. The
Othmer−Tobias and Hands parameters are reported in
Table S1 and S2. The NMR spectra of the [BPy][NO3]
is shown in as Figure S1. The variation of distribution
ratio with the mole fraction of aromatic hydrocarbons in
alkane rich phase for the ternary systems {[BPy][NO3]
(1) + alkane (2) + ethylbenzene (3)} are represented in
Figure S2 (PDF)
■ AUTHOR INFORMATION
Corresponding Author
*E-mail: mokhtaranib@ccerci.ac.ir. Tel.: +98 2144580770. Fax:
+98 2144580781.
ORCID
Babak Mokhtarani: 0000-0002-8230-5646
Notes
The authors declare no competing financial interest.
■ ACKNOWLEDGMENTS
The authors would like to thank the Iran National Science
foundation (INSF) for financial support of this research.
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