Solvent extraction of aromatic components from petroleum derived fuels: a perspective review

To chase the environmental regulations regarding the quality of fuels the global society calls for zero sulfur fuels. Therefore, the issue of the removal of aromatics from fuels has become more serious because the existence of aromatics in fuel hinders the production of ultra-low sulfur fuel. It creates an enormous interest amongst the scientific community worldwide in research involving the dearomatization of fuels. The present perspective review discusses the need for dearomatization, the concepts, advantages and disadvantages of various processes used for dearomatization together with advances in the dearomatization of hydrocarbon fuels, more specifically of diesel fractions by solvent extraction. The more challenging task required for the dearomatization of diesel fractions by solvent extraction is the selection of a proper solvent along with the optimum extraction conditions. This review reveals key solvents and extraction conditions influencing the removal of aromatic components from petroleum derived fractions. In addition, it demonstrates the dependence of solvent selection criteria on the properties and boiling range of the feedstock. It also demonstrates that each of the solvents used offers some advantages and disadvantages from a techno-economic point of view irrespective of the solvents used in a particular process.