@article{scholars12094,
           title = {Optimization and characterization of magnetite-reduced graphene oxide nanocomposites for demulsification of crude oil in water emulsion},
             doi = {10.1039/c9ra03304a},
          number = {41},
          volume = {9},
            note = {cited By 19},
           pages = {24003--24014},
       publisher = {Royal Society of Chemistry},
         journal = {RSC Advances},
            year = {2019},
          author = {Wai, M. M. and Khe, C. S. and Yau, X. H. and Liu, W. W. and Sokkalingam, R. and Jumbri, K. and Lwin, N.},
            issn = {20462069},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85070380832&doi=10.1039\%2fc9ra03304a&partnerID=40&md5=0c436566e43962deea48163e0a5ba53d},
        keywords = {Efficiency; Emulsification; Emulsions; Fourier transform infrared spectroscopy; Gas industry; Graphene; Iron oxides; Magnetite; Magnetite nanoparticles; Nanocomposites; Ostwald ripening; Spectrometers; Synthesis (chemical); Wastewater treatment; X ray photoelectron spectroscopy, Demulsification efficiency; External magnetic field; Field emission scanning; High separation efficiency; Reduced graphene oxides; Reduced graphene oxides (RGO); Response surface method; Vibrating sample magnetometry, Demulsification},
        abstract = {Oily wastewater from the oil and gas industry negatively affects the environment. Oily wastewater typically exists in the form of an oil-in-water emulsion. Conventional methods to treat oily wastewater have low separation efficiency and long separation time and use large equipment. Therefore, a simple but effective method must be developed to separate oil-in-water emulsions with high separation efficiency and short separation times. Magnetite-reduced graphene oxide (M-RGO) nanocomposites were used as a demulsifier in this work. Magnetite nanoparticles (Fe3O4) were coated on reduced graphene oxide (rGO) nanosheets via an in situ chemical synthesis method. The synthesized M-RGO nanocomposites are environmentally friendly and can be recovered after demulsification by an external magnetic field. M-RGO characterization was performed using X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, field emission scanning microscopy, Raman spectroscopy, and vibrating sample magnetometry. Demulsification performance was evaluated in terms of M-RGO dosage, effects of pH, and brine concentration. The demulsification capability of M-RGO was determined based on the residual oil content of the emulsion, which was measured with a UV-vis spectrometer. The response surface method was used to determine the optimum conditions of the input variables. The optimum demulsification efficiency achieved at pH 4 and M-RGO dosage of 29 g L-1 was approximately 96. This finding demonstrates that M-RGO nanocomposites are potential magnetic demulsifiers for oily wastewater that contains oil-in-water emulsions. Also, the recyclability of this nanocomposite has been tested and the results shown that it is a good recyclable demulsifier. {\^A}{\copyright} 2019 The Royal Society of Chemistry.}
}