Compared with plant-derived cellulose, developing biocellulose nanofibers (bio-CNFs) as a functional membrane material is of great interest in membrane filtration for the effective separation of emulsified oily wastewater due to its low cost, renewability, high water-holding capacity and anti-oil-fouling properties. In this work, a bio-CNF membrane was produced by cultured Gluconacetobacter xylinus through a simple biosynthetic process followed by a purification step involving alkali treatment. Herein, the bio-CNF membrane treated with 0.75 M NaOH solution formed a unique, porous nanonetwork structure with good hydrophilicity and ultralow-oil-adhesion properties, and this was successfully applied for the separation of surfactant-stabilized oil/water emulsions. The superhydrophilic and superoleophobic bio-CNF membranes exhibited superior performance for separating surfactant-stabilized oil/water emulsions, showing a separation efficiency of similar to 99% and a high permeate flux recovery ratio (above 94%) for long-term separation processes.
