Extractive Removal of Basic and Neutral Nitrogen Compounds from Naphtha and Kerosene by Deep Eutectic Solvents Based on Triethylamine and Aromatic Acids

In this study a class of DESs based on triethylamine (TEA) and aromatic acids was synthesized and used in the extractive denitrogenation of model oil fraction firstly. The structures of DESs were characterized by nuclear magnetic resonance and Fourier transform infrared spectrometer. The factors that influence extraction efficiency and distribution coefficient were investigated. The extraction performance of TEA/o-hydroxybenzoic acid (OHBA) is better than that of TEA/benzoic acid and TEA/o-methylbenzoic acid. The extraction efficiencies of quinoline and indole reach up to 99.1 and 98.3% only through two extraction stages, respectively. The extraction efficiency is not sensitive to reaction temperature and initial nitrogen content. The DESs based on TEA and aromatic acids exhibit excellent regeneration performance. In summary, the DESs based on TEA and aromatic acids are excellent extracting agents for basic and non-basic nitrogen compounds and will become promising extracting agents for the oil fraction denitrogenation.