Multifunctional CeO2-coated pulp/cellulose nanofibers (CNFs) membrane for wastewater treatment: Effective oil/water separation, organic contaminants photodegradation, and anti-bioadhesion activity

Complicated contaminants in wastewater, such as intractable oils, organic colors, and adhering organisms, have generated major environmental problems that are hazardous to ecosystems and human health, and wastewater purification is complex and difficult to achieve with a single substance or single process. A facile yet environmentally friendly technique for fabricating a superhydrophobic, oil-water separation, anti-bioadhesion, and photocatalytic Pulp/cellulose nanofibers (CNFs) membrane for all-in-one wastewater treatment is presented here. In this strategy, the hierarchical micro/nanostructured CeO2 nanoparticles and stearic acid (STA)-coated Pulp/CNF (Pulp/CNF-CeO2-STA) membrane is fabricated via a straightforward and easy-to-operate coating method, which simultaneously endows the membrane with superwetting ability, good oil-water separation capacity, notable photocatalytic degradation capacity, and outstanding anti-bioadhesion action. According to the experimental results, the suitably prepared Pulp/CNF-CeO2-STA membrane displayed superior superhydrophobicity (water contact angle: 166 ± 2°), high separation efficiency (88%), and high throughput (73 L·m−2·h−1). This Pulp/CNF-CeO2-STA membrane also showed significant photocatalytic degradation (>94%) of organic dye pollutants in water, as well as good anti-bioadhesive performance against Chlorella. As such, it serves several functions in wastewater treatment, considerably simplifying installation and saving money in application. In conclusion, this unique coating process is environmentally benign and very practicable, paving the door for the development of multi-functional materials in environmental treatments.