Electrospun PVDF-based cellulose stearoyl ester nanocomposites for effective separation of water-in-oil emulsions

Developing highly efficient and convenient nanofibrous composites holds great significance for the separation of water-in-oil emulsions. In this paper, we present a reusable porous fiber composite material obtained by using stearoyl chloride modified cellulose and polyvinylidene fluoride (PVDF) for electrospinning. The modified cellulose stearyl ester (CSE) enhances the hydrophobicity and lipophilicity of the composites. The PVDF/CSE-8:2 nanofibrous membrane exhibits a water contact angle of up to 155°, a separation flux of up to 2715 L·m−2·h−1, and a separation efficiency of over 97% under gravity for oil-water surfactant-stabilized emulsions. Simultaneously, the interaction between CSE and PVDF improves the mechanical properties of the nanofibrous membrane, with the tensile strength of the PVDF/CSE-8:2 nanofibrous membrane (24.3 MPa) being twice that of pure PVDF. Thus, composite nanofibrous membranes can be environmentally friendly through the use of sustainable, low-cost biomass resources to reduce the use of petroleum-based polymers. These properties give PVDF/CSE nanofibrous membranes great potential for commercial oil-water separation.