Simultaneous Extraction of Sulfur and Nitrogen Compounds from Model Diesel Fuel Using Neoteric Green Solvents.

Removal of nitrogen and sulfur compounds from diesel fuel is essential to comply with the increasing stringent regulations. The extraction capability of two deep eutectic solvents, namely, tetrabutylphosphoniumbromide/ethylene glycol, TBPBr/EG, with molar ratio 1:2, and tetrabutylammoniumbromide/ethylene glycol, TBABr/EG, with molar ratio 1:2, in simultaneously extracting basic nitrogen, nonbasic nitrogen, and sulfur compounds represented by pyridine, indoline, and dibenzothiophene (DBT) from -hexadecane, was investigated. Two pseudo-ternary phase diagrams of (TBPBr/EG + (pyridine + indoline + DBT) + -hexadecane) and (TBABr/EG + (pyridine + indoline + DBT) + -hexadecane) were predicted via a conductor-like screening model for real solvents (COSMO-RS) and experimentally validated at 298.