The Effect of Surfactant on Selectivity in the Extraction of Aromatic Hydrocarbons from the Lube Oil

Abstract

An investigation was conducted in order to examine the effect of the addition of surfactant to the fraction of the light lubricating oil (spindle) during the solvent extraction process. The solvent power and selectivity can be further increased by using surfactant as an additive. This could facilitate the separation phase and increase the yield of the raffinate. In this study, we suggested the use of ethoxylated anionic surfactant (sodium lauryl ether sulfate). The aromatics in the lube oil were extracted at different temperatures (ranging from 333.15 to 343.15 K) with different concentrations of surfactant (ranging from 0.01 to 0.1 wt%). The extraction temperature and the amount of surfactant in furfural were systematically investigated to determine their optimum values. Compositions in monoaromatics, diaromatics, polyaromatics, and saturates were determined by using UV–Vis spectrophotometry. When surfactant was added, the solvent acquired the ability to preferentially extract polyaromatics instead of the monoaromatics. This directly affects the required oil quality. It was found that using 0.01 wt% of surfactant at 343.15 K yields the optimum extraction conditions.