## 1 Introduction
On the other hand, a material is said to be hydrophobic (non-water wet material) if the water contact angle of the material is above 90\({}^{\circ}\). Hydrophilic materials have been used in many applications including environmental applications, water treatment, and biomedical applications [9]. A superhydrophobic surface made of Teflon (PTFE)-coated mesh film has been reported for oil/water mixture separation [10]. These hydrophobic membranes, however, are easily clogged by oil. As a result of that, the permeate flux and the oil removal are inefficient. As a result, superhydrophobic and superoleophobic membranes are better suited to separate water-rich oil/water mixtures or emulsions. The majority of commercial flat sheet membranes are made of oleophilic polymers (polyvinylidene fluoride, polypropylene, and so on), which are easily fouled by oil and result in decreased separation efficiency. Simultaneously, some polyethersulfone membranes with carbon nanotube or ZnO nanofillers have been fabricated using the traditional phase inversion method for oil/water separation. However, these membranes still suffer from the problem of segregated pore structure within the membrane matrix due to the conventional membrane fabrication process [11; 12]. High-energy materials with water-favoring properties were proposed for the construction of underwater superoleophobic membrane surfaces after being inspired by fish scales. Hydrogel-coated mesh, for example, was created with underwater superoleophobicity for separating oil/water mixtures and surfactant-stabilized emulsions [13; 14]. However, these polymer-based approaches have shortcomings when it comes to practical applications, such as the stability of polymeric coating under harsh conditions and long-term preservation for reuse [15]. Superoleophobic membranes for oil/water separation with high separation efficiency, superior oil-fouling resistance, and high environmental durability have been used sparingly in industry up to now. The membrane presented in this paper is made of nanofibers with interconnected porous structure with high separation efficiency for oil/saltwater emulsions and with oil residuals in the filtrates lower than environmental discharge standards (42 ppm). The high durability and performance of this nanofiber-based membrane are ensured by carbon nanofiber as mechanical scaffold and titanate nanofiber as functional materials. Meanwhile, due to its superhydroophilicity, the membrane has excellent antifouling properties. Most importantly, this new membrane has good durability in harsh environments while maintaining consistent water flux and separation efficiency. The new membrane has a small pore size that does not allow the passage of the emulsified oil through the membrane. This new membrane has a high potential for practical industrial applications due to its excellent oil/water separation efficiency, durability, fouling resistance, and low cost of fabrication. The properties of the new ultralong titanate nanofiber and carbon nanofiber membrane are described in Figure 1.  
The technology that will be developed in this research can find numerous application opportunities such as the produced water treatment and oil spill cleanup in the sea. * The produced water refers to the water that is returned to the surface through a well borehole. The quantity of produced water is increasing with increased volumes of global oil/gas production. This project will examine the feasibility of the synthesized membrane to treat produced water. * Oil spills can occur in the sea and cause a negative impact on the ocean and marine life. The major human activities that cause oil spills are land drainage and waste disposal, offshore drilling, and spills from ships or tankers. These practices form a saline oily wastewater that requires a treatment process. This work will examine the feasibility of the synthesized membrane to treat saline oily water.