Design of the Hydrocarbon Recovery Section from the Extract Stream of the Aromatic Separation from Reformer and Pyrolysis Gasolines Using a Binary Mixture of [4empy][Tf2N] + [emim][DCA] Ionic Liquids

Abstract

Reformer and pyrolysis gasolines are the main benzene, toluene, ethylbenzene, and xylenes (BTEX) sources. In our previous works, the aromatic extraction from reformer and pyrolysis gasoline models formed by three n-alkanes, benzene, toluene, and xylenes were studied using a binary mixture of ionic liquids (ILs). The results showed that the {[4empy][Tf2N] + [emim][DCA]} IL mixture with [4empy][Tf2N] mole fraction of 0.3 required a comparable countercurrent extraction column to that of the Sulfolane process, and extracted BTEX had quite a higher purity using the IL mixture in the three gasoline models analyzed. Here, we have studied the hydrocarbon recovery from the extract stream obtained in these works. For that purpose, the vapor–liquid equilibria (VLE) data involving the extracted hydrocarbons and the IL mixed solvent have been determined by the headspace–gas chromatography (HS–GC) technique for several temperatures. Afterward, the simulation of two new process configurations based on adiabatic flash di...