Liquid-Liquid Extraction of Naphthenic Acid Using Thiocyanate Based Ionic Liquids

The presence of carboxylic acids in the form of naphthenic acid in crude oil could cause severe corrosion problem during oil refinery. Therefore, this study is to investigate the potential of using ionic liquid as a non-volatile solvent for the extraction of naphthenic acid from a model hydrocarbon liquid that is dodecane. In this study, ionic liquid based on 1,8-diazobicyclo[5.4.0]undec-7-ene-hexyl [DBU-Hex] cation with anion thiocyanate [SCN] was synthesized for the naphthenic acid extraction. Liquid-liquid extraction for ternary system {dodecane + naphthenic acid + [DBU-Hex][SCN]} will be performed at constant temperature 25 within the specified feed compositions. Finally, the ternary phase diagrams will be developed and the experimental data will be compared with the tie lines correlated using NRTL or UNIQUAC model.