Article pubs.acs.org/jced
Vapor−Liquid Equilibrium Data for Binary Mixtures of Acetic Acid + Anisole, Acetone + Anisole, and Isopropanol + Anisole at Pressure 96.15 kPa Nilesh A. Mali,*,† Pawan K. Mali,‡ Asmita P. Patil,‡ and Sunil S. Joshi† †
Chemical Engineering and Process Development Division, CSIRNational Chemical Laboratory, Pune, Maharashtra, India Chemical Engineering Department, College of Engineering, Bharati Vidyapeeth Deemed University, Pune, Maharashtra, India
‡
ABSTRACT: In this work, the vapor−liquid equilibrium (VLE) data have been generated at the local atmospheric pressure of 96.15 kPa for the binary systems acetic acid + anisole, acetone + anisole, and isopropanol + anisole. A circulation type apparatus was designed and developed with few modifications in one of the stills proposed in the literature. For the validation of the new apparatus, VLE data were generated for the known system of N,N-DMF + aniline and compared with the literature data. The VLE data, generated in Txy form for all pairs, were found to be consistent through the point-to-point consistency test. Activity coefficient models, Wilson, NRTL, and UNIQUAC, were fitted to these data using an objective function of minimizing the sum of deviation between experimental and calculated total pressures to estimate the binary interaction parameters. The model predictions with estimated parameters were compared with the experimental data and found appropriate.
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INTRODUCTION Perfume and pharmaceutical industries play a crucial role in life of human beings. There is a huge demand for the variety of perfumes and drugs. Anisole is used as a precursor for perfumes due to its pleasant aromatic odor. It has also good demands from pharmaceutical and agrochemical industries as an intermediate chemical. It also finds an application in distillation as an entrainer in extractive distillation for separation of azeotropic mixtures. Hence, vapor−liquid equilibrium (VLE) data for anisole with various other solvents will be useful for designing separation equipment like distillation column, extraction column, and so forth. In the present work, isobaric VLE data in the form of Txy was generated for anisole with acetic acid, acetone, or isopropanol at local atmospheric pressure of 96.15 kPa. The data were also correlated with three activity coefficient models, Wilson, nonrandom two-liquid (NRTL), and universal quasichemical (UNIQUAC), and the binary interaction parameters were estimated.
Table 1. Components, Supplier, and Purity component
supplier
purity (mass %)
anisole acetic acid acetone isopropanol aniline N,N-dimethylformamide (N,N-DMF)
Spectrochem Loba Chemicals Loba Chemicals Spectrochem Loba Chemicals Loba Chemicals
99 99.9 99.8 99.8 99 99
Table 2. Specific Gravities, Refractive Indices (nD), and Boiling Points refractive index (nD) at 20 °Ca
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EXPERIMENTAL SECTION Materials. Details of the various chemicals used are as listed in Table 1. The chemicals were used as such without any further purification. Table 2 lists the reported specific gravities, reported and measured refractive indices (nD), and reported boiling points of the chemicals used. Apparatus and Procedure. In this study, the VLE experiments were carried out by using a glass dynamic type circulating still. The apparatus is based on a basic design of the still introduced by Raal and Muhlbauer.6 The schematic representation of the apparatus is shown in Figure 1. A mixing © 2017 American Chemical Society
a
compound
specific gravity1
literature
measureda
boiling point1 (°C) (at 101.325 kPa)
anisole acetic acid acetone isopropanol aniline N,N-DMF
0.99 1.049 0.792 0.786 1.022 0.945
1.51752 1.372243 1.358684 1.37505 1.586284 1.430474
1.51751 1.37241 1.36062 1.37582 1.58685 1.43181
154−5 118.1 56.5 82.6 184.4 152.8
Standard uncertainties u are u(nD) = 0.002, u(T) = 0.1 K.
Received: August 4, 2016 Accepted: January 30, 2017 Published: February 14, 2017 947
DOI: 10.1021/acs.jced.6b00700 J. Chem. Eng. Data 2017, 62, 947−953
Journal of Chemical & Engineering Data
Article
Figure 1. Experimental VLE apparatus.
Table 3. Antoine Equations and Constant Values Antoine constants sr. no.
compound
temperature range (K)
ref eq
A
B
C
1 2 3 4 5 6 7 8
anisolea anisoleb anisolec aniline acetonea acetic acidb isopropanolc N,N-DMF
314−4279 383.03−437.2610,16 383−42711 340−50012 259.16−507.6013,16 290−43014 356.24−424.2615,16 303−36312
4 3 4 3 4 4 3 3
7.110157 4.17726 14.2222 14.6574 4.42448 6.4302 4.8610 14.3536
1446.845 1489.756 3418.456 3857.52 1312.253 1479.01 1357.427 3541.51
−73.987 −69.607 −70.593 −73.15 −32.445 −56.34 −75.814 −62.76
units P P P P P P P P
= = = = = = = =
mbar, T = K bar, T = K kPa, T = K kPa, T = K bar, T = K kPa, T = K bar, T = K kPa, T = K
a Antoine constants used for the acetone + anisole system. bAntoine constants used for the acetic acid + anisole system. cAntoine constants used for the isopropanol + anisole system.
K. The vapor flows to the condenser L where it is condensed completely. Vapor condensate is collected in the receiver T and overflows to the mixing chamber K. The magnetic stirrer in mixing chamber is set at a suitable rpm for proper mixing of incoming liquids. Equilibrium liquid and vapor condensate mixes well in the mixing chamber and overflows back to the boiling chamber. Thus, continuous recirculation of the liquid and vapor gets established in the still. The mixture was allowed to circulate for a sufficient amount of time to attain equilibrium which was first indicated by the constant temperature of the temperature sensors C in the equilibrium chamber. RTD type temperature sensors were used with ±0.1 K accuracy. Once a constant temperature was achieved, both liquid and vapor sample were analyzed for composition using refractometer. The liquid-phase sample was collected at point S1, and the vapor-phase sample was collected at point S2. At the liquid sample collection point S1, side coil arrangement was done for proper mixing of the liquid. At vapor collection point S2, a magnetic stirrer was provided for proper mixing and to obtain the uniform composition. As the refractometer needs a very small amount of sample to measure refractive index, a very small amount of samples (
