(Liquid + Liquid) Equilibrium for Ternary System of (Water + Phenol + ...
International Journal of Chemoinformatics and Chemical Engineering, 3(2), 75-84, July-December 2013 75
(Liquid + Liquid) Equilibrium for Ternary System of (Water + Phenol + Cyclohexane) at T = 298.2 K Hossein Ghanadzadeh, University of Guilan, Rasht, Iran Milad Sangashekan, University of Guilan, Rasht, Iran Shahin Asan, University of Urmia, Urmia, Iran
ABSTRACT Experimental solubility curves and tie-line data for the (water + phenol + 2-ethyl-1-hexanol) system was obtained at T = 298.2 K and atmospheric pressure. The tie-line data was determined by techniques karlfischer and refractometry. This ternary system exhibits type-2 behavior of LLE. Distribution coefficients and separation factors were measured to evaluate the extracting ability of the solvent. The consistency of the experimental tie-line data was determined through the Othmer–Tobias and Bachman equations. The data were correlated with the NRTL (α = 0.25) and UNIQUAC models and the parameters estimated present root mean square deviations below 0.50%. Keywords:
Cyclohexane, Extraction, Liquid + Liquid Equilibrium (LLE), NRTL, Phenol, UNIQUAC
INTRODUCTION Liquid + liquid equilibrium (LLE) investigations for ternary aqueous mixtures of phenol with organic solvents are important in evaluation of industrial solvent extraction units. Accurate ternary equilibrium data are always needed for efficient separation of phenol from water. One of the important sections of the petrochemical industry is phenol production,
especially for the production of resins (Matar & Hatch, 2001). Phenol is formed by oxidation of cumene in liquid phase, leading to cumene hydroperoxide (CHP); in following order: the CHP suffer a catalytic decomposition, producing phenol and acetone with water and α-methyl styrene as byproducts. So, a stream including phenol, water and small amounts of acetone and α-methyl styrene is produced at the end of the process (Speight, 2002). The remotion of
DOI: 10.4018/ijcce.2013070105 Copyright © 2013, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited.
76 International Journal of Chemoinformatics and Chemical Engineering, 3(2), 75-84, July-December 2013
phenol from aqueous solutions is an environmental interest for a very toxic stream (Dohnal & Fenclová, 1995). To remove phenol from wastewater, liquid extraction can be more economically feasible than distillation, since these streams contain low concentrations of phenol and (phenol + water) forms an azeotrope at 9.2 wt% of phenol (Pinto et al., 2005). Additionally, Brazilian law restricts the mass fraction of total phenol from (0.3×10−6 to 1.0×10−6 ) wt% in fresh water, 6.0×10−6 wt% in salt water, and 0.3×10−6 wt% in brackish waters. Various solvents have been proposed for this process. According to the authors, the esters are most appropriate for the separation of phenol from water because of their present better selectivity ratio versus distribution coefficient results (González et al., 1986). The distribution coefficients of phenol for systems (water + phenol + 1-decanol) and (water + phenol + tridecanol) have been published at T = 293.15 K (Scott et al, 1992). The LLE data for the systems (water + phenol + tert-butanol) at 298.15 K and (water + phenol + 1-butanol), (water + phenol + 2-butanol) are reported at T = (298.15 and 313.15) K (Oliveira & Aznar, 2010). The systems (water +phenol + dimethyl carbonate), (water + phenol + diphenyl carbonate) have been studied at T = 358.15 K (Hwang & Park, 2011).
EXPERIMENTAL Material The phenol and 2-ethyl-1-hexanol with stated mass fraction purities higher than 0.99 were purchased from Chem-lab and Merck, respectively. The organic chemicals were dried over
molecular sieves. Distilled and deionised water was used throughout all experiments. All materials were used as received without any further purification. Some measured physical properties for the chemicals used in this study along with the literature values are listed in (Table 1).
Apparatus and Procedure The solubility curve (binodal) was determined by the cloud point method in an equilibrium glass cell with a water jacket to maintain isothermal conditions. The temperature of the cell was controlled by a water jacket and maintained with an accuracy of within ±0.1 K. At each system, the third component was progressively added using a microburet. The end-points were determined by observing the transition from an appearance to disappearance mixtures. All the measurements were repeated at least three times. The average of these readings was taken for the component compositions (Table 2). A 250 cm3 glass cell connected to a thermostat was used to measure the tie-line data. The equilibrium data were determined by preparing the ternary mixtures of known compositions. The prepared mixtures were agitated vigorously for at least 4 h, and then left to settle for 5 h for complete phase separation. For these ternary systems, this time long enough to achieve equilibrium. When the equilibrium was attained, the system separated into two liquid phases that become clear and transparent with a well-defined interface. The sample of the organic-rich phase was carefully taken from the top sampling port of a syringe, and that of the water-rich phase was taken from a bottom sampling port of the cell.
Table 1.The refractive index (n) and density (ρ) of the pure components at T = 298.2 K n
ρ(Kg.m-3)
Exp.
Lit.
Exp.
Lit
cyclohexane
1.4234
1.4235 (Mora′vkova′ et al., 2007)
773.86
773.89 (Mora′vkova′ et al., 2007)
Water
1.3325
1.3325 (Ghanadzadeh Gilani et al.,2011)
997.06
997.04 (Ghanadzadeh Gilani et al.,2011)
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(Liquid + Liquid) Equilibrium for Ternary System of (Water + Phenol + Cyclohexane) at T = 298.2 K Hossein Ghanadzadeh, University of Guilan, Rasht, Iran Milad Sangashekan, University of Guilan, Rasht, Iran Shahin Asan, University of Urmia, Urmia, Iran
ABSTRACT Experimental solubility curves and tie-line data for the (water + phenol + 2-ethyl-1-hexanol) system was obtained at T = 298.2 K and atmospheric pressure. The tie-line data was determined by techniques karlfischer and refractometry. This ternary system exhibits type-2 behavior of LLE. Distribution coefficients and separation factors were measured to evaluate the extracting ability of the solvent. The consistency of the experimental tie-line data was determined through the Othmer–Tobias and Bachman equations. The data were correlated with the NRTL (α = 0.25) and UNIQUAC models and the parameters estimated present root mean square deviations below 0.50%. Keywords:
Cyclohexane, Extraction, Liquid + Liquid Equilibrium (LLE), NRTL, Phenol, UNIQUAC
INTRODUCTION Liquid + liquid equilibrium (LLE) investigations for ternary aqueous mixtures of phenol with organic solvents are important in evaluation of industrial solvent extraction units. Accurate ternary equilibrium data are always needed for efficient separation of phenol from water. One of the important sections of the petrochemical industry is phenol production,
especially for the production of resins (Matar & Hatch, 2001). Phenol is formed by oxidation of cumene in liquid phase, leading to cumene hydroperoxide (CHP); in following order: the CHP suffer a catalytic decomposition, producing phenol and acetone with water and α-methyl styrene as byproducts. So, a stream including phenol, water and small amounts of acetone and α-methyl styrene is produced at the end of the process (Speight, 2002). The remotion of
DOI: 10.4018/ijcce.2013070105 Copyright © 2013, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited.
76 International Journal of Chemoinformatics and Chemical Engineering, 3(2), 75-84, July-December 2013
phenol from aqueous solutions is an environmental interest for a very toxic stream (Dohnal & Fenclová, 1995). To remove phenol from wastewater, liquid extraction can be more economically feasible than distillation, since these streams contain low concentrations of phenol and (phenol + water) forms an azeotrope at 9.2 wt% of phenol (Pinto et al., 2005). Additionally, Brazilian law restricts the mass fraction of total phenol from (0.3×10−6 to 1.0×10−6 ) wt% in fresh water, 6.0×10−6 wt% in salt water, and 0.3×10−6 wt% in brackish waters. Various solvents have been proposed for this process. According to the authors, the esters are most appropriate for the separation of phenol from water because of their present better selectivity ratio versus distribution coefficient results (González et al., 1986). The distribution coefficients of phenol for systems (water + phenol + 1-decanol) and (water + phenol + tridecanol) have been published at T = 293.15 K (Scott et al, 1992). The LLE data for the systems (water + phenol + tert-butanol) at 298.15 K and (water + phenol + 1-butanol), (water + phenol + 2-butanol) are reported at T = (298.15 and 313.15) K (Oliveira & Aznar, 2010). The systems (water +phenol + dimethyl carbonate), (water + phenol + diphenyl carbonate) have been studied at T = 358.15 K (Hwang & Park, 2011).
EXPERIMENTAL Material The phenol and 2-ethyl-1-hexanol with stated mass fraction purities higher than 0.99 were purchased from Chem-lab and Merck, respectively. The organic chemicals were dried over
molecular sieves. Distilled and deionised water was used throughout all experiments. All materials were used as received without any further purification. Some measured physical properties for the chemicals used in this study along with the literature values are listed in (Table 1).
Apparatus and Procedure The solubility curve (binodal) was determined by the cloud point method in an equilibrium glass cell with a water jacket to maintain isothermal conditions. The temperature of the cell was controlled by a water jacket and maintained with an accuracy of within ±0.1 K. At each system, the third component was progressively added using a microburet. The end-points were determined by observing the transition from an appearance to disappearance mixtures. All the measurements were repeated at least three times. The average of these readings was taken for the component compositions (Table 2). A 250 cm3 glass cell connected to a thermostat was used to measure the tie-line data. The equilibrium data were determined by preparing the ternary mixtures of known compositions. The prepared mixtures were agitated vigorously for at least 4 h, and then left to settle for 5 h for complete phase separation. For these ternary systems, this time long enough to achieve equilibrium. When the equilibrium was attained, the system separated into two liquid phases that become clear and transparent with a well-defined interface. The sample of the organic-rich phase was carefully taken from the top sampling port of a syringe, and that of the water-rich phase was taken from a bottom sampling port of the cell.
Table 1.The refractive index (n) and density (ρ) of the pure components at T = 298.2 K n
ρ(Kg.m-3)
Exp.
Lit.
Exp.
Lit
cyclohexane
1.4234
1.4235 (Mora′vkova′ et al., 2007)
773.86
773.89 (Mora′vkova′ et al., 2007)
Water
1.3325
1.3325 (Ghanadzadeh Gilani et al.,2011)
997.06
997.04 (Ghanadzadeh Gilani et al.,2011)
Copyright © 2013, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited.
8 more pages are available in the full version of this document, which may be purchased using the "Add to Cart" button on the product's webpage: www.igi-global.com/article/liquid-liquid-equilibrium-ternarysystem/78489?camid=4v1
This title is available in InfoSci-Journals, InfoSci-Journal Disciplines Engineering, Natural, and Physical Science. Recommend this product to your librarian: www.igi-global.com/e-resources/libraryrecommendation/?id=2
Related Content Extension of Ugi's Scheme for Model-Driven Classification of Chemical Reactions Shyantani Maiti, Sanjay Ram and Somnath Pal (). International Journal of Chemoinformatics and Chemical Engineering (pp. 26-51).
www.igi-global.com/article/extension-of-ugis-scheme-for-model-drivenclassification-of-chemical-reactions/133557?camid=4v1a Wavy Motion of Viscous Bubbly Liquid in Tubes of Orthotropic Material Rafael Yusif Amenzadeh, Akperli Reyhan Sayyad and Faig Bakhman Ogli Naghiyev (2012). International Journal of Chemoinformatics and Chemical Engineering (pp. 3947).
www.igi-global.com/article/wavy-motion-viscous-bubblyliquid/63433?camid=4v1a Technical and Marketing Criteria for the Development of Fast Pyrolysis Technologies Juan Miguel Mesa-Pérez and Felix Fonseca Felfli (2015). Innovative Solutions in Fluid-Particle Systems and Renewable Energy Management (pp. 274-297).
www.igi-global.com/chapter/technical-and-marketing-criteria-for-thedevelopment-of-fast-pyrolysis-technologies/132888?camid=4v1a
Photovoltaic Devices Ashraf Uddin (2013). Handbook of Research on Solar Energy Systems and Technologies (pp. 126-162).
www.igi-global.com/chapter/photovoltaic-devices/69088?camid=4v1a
