Section 2 Ionic Liquids

Macromolecular Symposia. 2017;375: 1600202. DOI: 10.1002/masy.2016

Solvents, Ionic Liquids and Solvent Effects

[29] Buzin P, Yablokova M, Kuznetsov A, Smirnov A, Abramov I. New AB polyetherimides obtained by direct

aminophenoxy phthalic acids. High Performance Polymers. 2004;16: 505-514. DOI: 10.1177/09540083040

[30] Gao H. Development of star

[31] Sugi R, Hitaka Y, Yokoyama A, Yokozawa T. Well-defined star-shaped aromatic polyamides from chain-growth

Macromolecules. 2005;38:5526-5531.

Tokmashev R, Tsegelskaya A, Semenova G, Shakhnes A, et al. Synthesis of reactive three-arm star-shaped oligoimides with narrow molecular weight distribution. Journal of Polymer Science, Part A: Polymer Chemistry. 2018;56:2004-2009. DOI: 10.1002/

10.1002/marc.201200005

polymerization of phenyl 4- (alkylamino)benzoate with multifunctional initiators.

DOI: 10.1021/ma0473420

pola.29088

2345-7

64

[32] Kuznetsov A, Soldatova A,

[33] Tsegelskaya A, Soldatova A, Semenova G, Dutov M, Abramov I, Kuznetsov A. One-stage high

[34] Soldatova A, Tsegelskaya A, Semenova G, Abramov I, Kuznetsov A. Synthesis of tetrafunctional aromatic amines and star-shaped oligoimides using the B4+AB scheme. Russian Chemical Bulletin. 2018;67:2152-2154. DOI: 10.1007/s11172-0182345-7

temperature catalytic synthesis of starshaped oligoimides by (B4+AB) scheme. Polymer Science, Series B. 2019;61: 148-154. DOI: 10.1007/s11172-018-

polymers as unimolecular containers for nanomaterials. Macromolecular Rapid Communications. 2012;33:722-734. DOI:

polycyclocondensation of

00202

39991

**67**

**Chapter 4**

**Abstract**

**1. Introduction**

than 90% for pyrolysis gasoline [1].

*and Sandra Corderí*

Extraction of Aromatic

Compounds from Their Mixtures

with Alkanes: From Ternary to

Quaternary (or Higher) Systems

*Ángeles Domínguez, Begoña González, Patricia F. Requejo* 

Ionic liquids have been proposed as separation agents for liquid extraction of aromatic compounds from their mixtures with alkanes, with the aim of improving the separation process and replacing conventional organic solvents. A significant number of experimental liquid-liquid equilibrium data for ternary system alkane + aromatic compound + ionic liquid can be found in literature; however there are few data for quaternary or higher systems involving more than one aliphatic compound, several aromatic compounds or a mixture of ionic liquids as separation agent. These data are also necessary because molecular interactions between the compounds in the mixture can modify the affinity of the solvent for the aromatic compound of interest. In this chapter we review the published data involving more than three components, and we present new liquid-liquid equilibrium data for the quaternary systems heptane + cyclohexane + toluene +1-ethyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide and heptane + cyclohexane + toluene +

1-hexyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide.

Aromatic compounds, such as benzene, toluene, ethylbenzene and xylenes (BTEX), are raw materials for the production of polymers, resins paints and other products of industrial interest. They are mainly obtained from catalytic reforming and cracking processes in oil refineries, as a mixture of aromatic and aliphatic hydrocarbons. Aromatic content depends on the process characteristics, and it can range between 20 and 65 wt% for reformate gasoline and between 50 and more

The separation of aromatic from aliphatic compounds is difficult because they

usually have close boiling points and many of their mixtures show azeotropic behaviour. One of the most used processes to separate these aromatic compounds is liquid-liquid extraction, due to the fact that it can be used for a wide range of aromatic concentration in the mixture. Sulfolane, among other solvents, is widely used in these processes because of its high selectivity (S) for aromatics although it is

**Keywords:** ionic liquids, aromatic compounds, liquid extraction
