Isobaric VLE data for 1-methyl-3-ethylbenzene or 1-methyl-4-ethylbenzene + 1, 2, 4-trimethylbenzene at 20 kPa
Highlights
► VLE data of 1E3MB or 1E4MB and 124TMB at 20 kPa were measured. ► VLE data were correlated by three models of Wilson, NRTL, and UNIQUAC. ► Different deviation behavior was observed for the two systems investigated.
Introduction
Mixtures of aromatic hydrocarbons with nine carbon atom (C9) are important byproduct of reforming unit in petroleum processing. After 1, 3, 5-trimethylbenzene (denoted as 124TMB) is drawn using extraction distillation [1], [2], [3], the residual streams are mainly composed of 1, 2, 4-trimethylbenzene (denoted as 124TMB), 1-methyl-3-ethylbenzene (denoted as 1E3MB), 1-methyl-4-ethylbenzene (denoted as 1E4MB) from here onwards and other impurities.
VLE data at the operating pressure are indispensable for separation by distillation. Among the studies on (vapor + liquid) equilibrium data determination of C9 aromatic hydrocarbons, isobaric data of 135TMB + 124TMB at 98.7 kPa have been measured by Liu et al. [4].
In the present study, to separate 124TMB from the residual streams, we measured the isobaric VLE data for the two binary systems of 1E3MB or 1E4MB and 124TMB at 20 kPa by using a modified Rose–Williams type recirculation still. The determined VLE data were verified with the thermodynamic consistency test described by Herington and improved by Abobott and Van Ness [5], [6]. Three activity coefficient models of Wilson [7], nonrandom two-liquid (NRTL) [8], and universal quasichemical (UNIQUAC) [9] were adopted to correlate the investigated experimental data.
Section snippets
Chemicals
Both 1E3MB (AR) and 1E4MB (AR) supplied by Shanghai Chemical Reagent Corporation (China), were further purified by distillation. 124TMB, supplied by Jinling Petroleum Chemical Corporation, was used without further purification. All of the chemicals have been analyzed by gas chromatography (SP6890A, Shandong Lunan Ruihong Chemical Instruments Co., Ltd China). The densities and refractive indexes of two components were measured by a digital vibrating-tube densimeter (DMA 4500, Anton Paar,
Experimental data
The measured isobaric VLE data for the two binary systems of 1E3MB (1) or 1E4MB (1) + 124TMB (2) at 20 kPa were listed in TABLE 2, TABLE 3, respectively. T–x–y phase diagrams of the two systems, illustrated in FIGURE 1, FIGURE 2 showed no azeotropic behavior.
Thermodynamic consistency test
Herington area test method [5], [6] was used to check the thermodynamic consistency for all the experimental data. According to Herington method, if D − J < 10, the experimental data would be considered thermodynamically consistent, in which D and
Conclusions
(Vapor + liquid) equilibrium data of 1E3MB or 1E4MB + 124TMB systems at 20 kPa were measured by using a modified Rose–Williams type still. NRTL, Wilson, and UNIQUAC model parameters were obtained with satisfactory correlation. Slightly better correlation results were observed with the UNIQUAC model for 1E3MB + 124TMB and the Wilson model for 1E4MB + 124TMB. The experimental data does not exhibit any azeotropic behavior for the two binary systems. The measured (vapor + liquid) equilibrium data provide the
References (14)
- et al.
Fluid Phase Equilib.
(2013) - et al.
Chem. Ind. Times
(2001) - et al.
Henan Chem. Ind.
(2006) - Y. Cao, The study of distillation integrated technology to extract light fraction from C9 aromatic in hydrocracking...
- et al.
Sci. Tech. Info.
(2008) J. Inst. Pet.
(1951)- et al.
Theory and Problems of Thermodynamics
(1972)
Cited by (3)
Modeling and simulation of diluent recovery unit in PUREX solvent regeneration system
2018, Progress in Nuclear Energy