Bio-inspired fabrication of highly permeable and anti-fouling ultrafiltration membranes based on bacterial cellulose for efficient removal of soluble dyes and insoluble oils

Ultrafiltration (UF) has been broadly applied for the supply of drinking water to achieve the interception of various organic, inorganic and biological pollutants. However, fouling is a ubiquitous problem when the filter is working. Thus, the development of high-performance ultrafiltration membrane with great separation abilities and anti-fouling properties is of particular importance in water treatment. In this work, we find a feasible way to use the mussel-inspired dopamine (DA) to modify the 3D web-like skeleton of bacterial cellulose (BC) in liquid phase, integrating with 2D graphene oxide (GO) nanosheets to fabricate a robust anti-fouling ultrafiltration membrane. The as formed bacterial cellulose/polydopamine/reduced graphene oxide (BC/PDA/RGO) composites showed unique superhydrophilicity and underwater superoleophobicity. For pure water flux test, the membrane exhibited high permeability of 1149.3 L m−2 h−1 under 0.1 MPa. For dyes and oils rejection experiment, the membrane revealed extraordinary contaminants resistance performances. More importantly, during cycling measurement, the membrane manifested superior anti-fouling capability and a high permeate flux recovery ratio (~96.9%) for long-term filtration processes. Therefore, this novel BC/PDA/RGO ultrafiltration membrane is expected as a promising candidate for water purification.