Technical Evaluation of Ionic Liquid-Extractive Processing of Ultra Low Sulfur Diesel Fuel

Recent trends in legislation across the world are aimed toward the reduction of the levels of sulfur in fuel oils to less than 10 ppm (ultra low sulfur diesel, ULSD) due to its toxic and environmental effects. Hydrodesulfurization (HDS) is the current method used for desulfurization and faces technical challenges, due to the extreme conditions and energy consumption necessary to reach low sulfur levels. Recently, ionic liquid (IL) technology has been proposed as a possible solution toward achieving ULSD. ILs represent a new class of “green” solvents that are gaining popularity due to their favorable properties and have recently been shown to be effective extractants for desulfurization on a laboratory scale. In this work, the feasibility of industrial scale IL-extractive processing of ULSD has been examined via the simulation and optimization of a conceptual process in ASPEN Plus. The widely used [Cnmim] [NTF2] series of ionic liquids have been employed, due to their favorable properties and the availabil...