▎ 摘　　要

A bifunctional demulsifier of ODTS modified magnetite/reduced graphene oxide (MRGO@ODTS) was synthesized and demonstrated to demulsify effectively both water-in-oil (W/O) and oil-in-water (O/W) emulsions, benefitting from its surfactant property. The demulsifier was fully characterized with TEM, XRD, FTIR, TGA, and magnetometer instruments, which confirmed the evenly Fe3O4 nanoparticle modified RGO sheet structure of MRGO@ODTS demulsifier. The demulsification efficiency can reach 96.8 +/- 2.9% for W/O emulsion and 97.9 +/- 2.1% for O/W emulsion with 25 g L-1 and 75 g L-1 demulsifier, respectively. Another important feature of MRGO@ODTS is responsive to magnetic field, and consequently reusable. The recyclability tests of MRGO@ODTS show there is no obvious decline of demulsification efficiency within ten cycles. The demusification ability of MRGO@ODTS is more effective for W/O emulsions than that for O/W emulsions. The possible demulsification mechanism was also proposed. The bifunctional demulsifier may find great potential in oil-water separation in industry.