@article{scholars15020,
           pages = {9629--9637},
          number = {14},
           title = {Ultrasonic-Assisted Technique as a Novel Method for Removal of Naphthenic Acid from Model Oil Using Piperidinium-Based Ionic Liquids},
          volume = {6},
             doi = {10.1021/acsomega.1c00189},
         journal = {ACS Omega},
            year = {2021},
       publisher = {American Chemical Society},
            note = {cited By 2},
          author = {Khaidzir, S. and Masri, A. N. and Ruslan, M. S. H. and Abdul Mutalib, M. I.},
            issn = {24701343},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104943207&doi=10.1021\%2facsomega.1c00189&partnerID=40&md5=b03a7a3e858b3a3c15e8f77e7d2deaf9},
        abstract = {In this study, piperidinium-based ionic liquids (IL) containing trifluoromethanesulfonate, phenolate, and dicyanamide anions were synthesized. Using the ILs, extraction of naphthenic acid from highly acidic oil with a total acid number (TAN) of 1.44 was studied. Two agitation techniques have been implemented for the extraction process, which were mechanical stirring and ultrasonic-assisted irradiation. 1-Butyl-1-methylpiperidinium phenolate BMPiPhe showed the best potential in extracting naphthenic acid from oil, with complete removal of naphthenic acid with IL-to-oil ratios of 0.010 and 0.0025 for the mechanical stirring method and the ultrasonic-assisted method, respectively. Ultrasonic-assisted extraction process shows very good potential in enhancing the extraction efficiency of naphthenic acid. Optimization and study on the effects of ultrasonic parameters, namely, IL-to-oil ratio, ultrasonic amplitude, and time, were studied through response surface methodology (RSM). Using BMPiPhe, the optimum conditions obtained are IL-to-oil ratio of 0.03, 53.91\% of amplitude, and 4.29 min of extraction time. Under these optimum conditions, 100\% removal of naphthenic acid was achieved. {\^A}{\copyright} 2021 The Authors. Published by American Chemical Society.}
}