Removal of naphthenic acids from diesel fuel using an ionic liquid

Naphthenic acids in diesel were removed by ionic liquid 2-ethylimidazole and sodium hydroxide. Single-factor experiments were done to review the effects of process parameters on removing acids. The process parameters included mass ratio of deacidification agents to diesel, mass ratio of 2-ethylimidazole to sodium hydroxide, reaction temperature, reaction time, and resting time. The orthogonal experiments were done to optimize the deacidification process, and the optimum deacidification process was that reaction temperature was 83 degrees C, reaction time was 5min, mass ratio of 2-ethylimidazole to sodium hydroxide was 1:1.5, mass ratio of deacidification agents to diesel was 0.20:1, and resting time was 5min. Under the optimum process, the deacidification rate reached 96.83%. The acidity number of diesel was reduced from 135.52 to 4.30mg KOH/100mL.