Extraction of propylbenzene from its mixtures with heptadecane using 4-methyl-N-butylpyridinium tetrafluoroborate

The separation of aromatic and aliphatic compounds from their mixtures is an important goal in chemical operations that produce both types of compounds. In petroleum industries, the properties of middle distillate fuels can be improved using dearomatization processes. The ionic liquid (IL), 4-methyl-N-butylpyridinium tetrafluoroborate [(mebupy)(BF4)], was evaluated as a solvent for the extraction of propylbenzene from its mixtures with high molar mass n-alkane. Liquid–liquid equilibria (LLE) for a ternary system heptadecane + propylbenzene + [(mebupy)(BF4)] was measured over a temperature range (313–333) K and at different solvent to feed ratios. The reliability of the experimental data was tested using the Othmer–Tobias correlation. The effect of temperature and solvent to feed ratio upon solubility, selectivity, and distribution coefficient were investigated experimentally. In addition, the UNIQUAC and the NRTL models were verified to accurately correlate the experimental data. A proposal of extraction process with this IL as a solvent was simulated by conventional software.

► (Mebupy)(BF4) was evaluated for propylbenzene and heptadecane separation.
► Reliability of the experimental data was ascertained by Othmer–Tobias correlation.
► Effect of solvent to feed ratio upon separation factors were investigated.
► UNIQUAC and NRTL models correlate the experimental data satisfactorily.
► Single stage extraction process was simulated by HYSYS.