Greener approach for the separation of naphthenic acid from model oil using Pyrrolidinium-based amino acid ionic liquids

Four novel pyrrolidinium-based amino acid ionic liquids were synthesized and characterized. The physicochemical properties of these amino acid ionic liquids (AAILs), such as viscosity, density, thermal stability, and surface tension were investigated. These ionic liquids (ILs) were used as a green chemistry approach for the extraction of naphthenic acid from the model oil. The influence of amino acid anions on the de-acidification process was assessed by attaching prolinate, glycinate, alaninate and serinate. Extraction results show that very small amounts of ILs are sufficient to extract naphthenic acid from a model oil configuration with a high total acid number. The regeneration and reusability of the synthesized ILs have also been analysed in this work. Moreover, the antimicrobial activity assay was performed to ascertain the potential toxicological effect of the synthesized set on the aquatic system. © 2022 Elsevier Ltd