Magnetically recoverable magnetite-reduced graphene oxide as a demulsifier for surfactant stabilized crude oil-in-water emulsion by Cozzoli, P. Davide, Yau, Xin Hui, Khe, Cheng Seong, Mohamed Saheed, Mohamed Shuaib, Lai, Chin Wei, You, Kok Yeow, Tan, Wai Kian