@article{scholars11695,
            year = {2019},
           pages = {1269--1276},
       publisher = {Center for Environmental and Energy Research and Studies},
         journal = {International Journal of Environmental Science and Technology},
             doi = {10.1007/s13762-018-1735-6},
            note = {cited By 14},
          volume = {16},
          number = {3},
           title = {Phosphonium-based hydrophobic ionic liquids with fluorous anions for biodiesel production from waste cooking oil},
        keywords = {Biodiesel; Catalysts; Fourier transform infrared spectroscopy; Ionic liquids; Methanol; Nuclear magnetic resonance spectroscopy; Optimization; Physicochemical properties; Potassium hydroxide; Synthetic fuels; Transesterification, American society for testing and materials; Biodiesel production; Catalytic transesterification; Heating temperatures; Hydrophobic ionic liquid; Phosphonium-based ionic liquids; Physio-chemical properties; Transesterification reaction, Oils and fats, anion; biofuel; catalysis; catalyst; cation; chemical compound; chemical reaction; detection method; heating; hydrophobicity; ionic liquid; optimization; physicochemical property; sulfuric acid; temperature effect},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85062629945&doi=10.1007\%2fs13762-018-1735-6&partnerID=40&md5=adef34ce3f5e6d4febf9fcdff152257b},
        abstract = {In this work, ionic liquids (ILs) containing the phosphonium cation and four different types of fluorous anions were synthesized and characterized with nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, elemental analyser (CHNS) and thermogravimetric techniques. The catalytic transesterification properties of the prepared ILs were investigated through the synthesis of biodiesel from waste cooking oil (WCO). The biodiesel synthesis was performed in two-step processes. Initially, the WCO was esterified with sulphuric acid to reduce its acid value (0.7{\^A} mg KOH/g). Later the transesterification reaction was carried out with the prepared ILs, and the process was optimized with respect to IL types, catalyst loading, methanol{\^a}??oil ratios, temperature, agitation speed and time. Tetrabutylphosphonium bis(trifluoromethylsulfonyl)imide (TBPNTf2) was identified as a promising catalyst with the highest yield of biodiesel up to 81\% at 4.5 wt\% of IL loading, 18:1 ratio of methanol:WCO, 10{\^A} h of treatment time, 60{\^A} {\^A}oC heating temperature and 600{\^A} rpm of agitation speed. The obtained product of biodiesel was characterized and analysed by different techniques, and its physicochemical properties were further determined using the known standard methods of American Society for Testing and Materials and European standards (ASTM and EN). {\^A}{\copyright} 2018, Islamic Azad University (IAU).},
            issn = {17351472},
          author = {Ullah, Z. and Bustam, M. A. and Man, Z. and Khan, A. S. and Sarwono, A. and Muhammad, N. and Farooq, M. and Shah, S. N. and Ahmad, P. and Haider, S.}
}