Facile preparation of superhydrophilic/underwater superoleophobic cellulose membrane with CaCO₃ particles for oil/water separation

The oily wastewater has been widely concerned owing to growing industrial wastewater and marine pollution. Herein, a cellulose-based oil/water separation membrane was fabricated using a very simple alternating soaking process (ASP). First, the sodium alginate was coated on the cellulose membrane surface (filter paper), and then CaCO₃ particles were assembled onto the membrane surface through ASP, finally we can get the superhydrophilic/underwater superoleophobic cellulose membrane (FP@SA/CaCO₃) for oil/water separation. The underwater oil contact angle (OCA) of FP@SA/CaCO₃ is 151.1°, which indicated that FP@SA/CaCO₃ has good underwater superoleophobicity. Moreover, for different oil/water mixtures, the FP@SA/CaCO₃ membrane has outstanding separation efficiency of over 99.2 % and the flux of over 400 L m⁻² h⁻¹. Besides, even after 20 reuse, FP@SA/CaCO₃ still showed a high flux and separation efficiency, indicating FP@SA/CaCO₃ has good reusability. The FP@SA/CaCO₃ membrane with low cost and high performance shows a good application market for oily wastewater remediation in the future.