Multilayered chitosan/kaolin@calcium carbonate composite films with excellent chemical and thermal stabilities for oil/water filtration realized by a facile layer-by-layer assembly

Herein, a novel separation mesh membrane with chitosan/kaolin@calcium carbonate (CS/KL@CaCO3) coating was fabricated via a facile and eco-friendly approach. Owing to the hierarchical micro/nano-structure and high hydrophilicity of the composite coating, the decorated membrane demonstrates outstanding superhydrophilicity in air and underwater anti-oil-fouling capability. The membrane can realize efficient separation to various light oil/water mixtures, and the separation efficiencies are > 98.0%. Especially, there is no obvious change in the separation efficiency after the reuse of 80 cycles, suggesting its good recyclability. In addition, the membrane displays satisfactory corrosion resistance and hot water resistance, and is applicable for the removal of corrosive solutions or hot water in oils. The high separation efficiency, excellent oil-repelling capability underwater, and readily scaled-up fabrication procedure of the membrane suggest enormous application potential in dealing with oil spills and separating oily wastewater.

Automated summary

A novel separation mesh membrane with outstanding separation efficiency and recyclability was fabricated using a simple and eco-friendly approach. The membrane features hierarchical micro/nano-structure and high hydrophilicity, exhibiting anti-oil-fouling capability both in air and underwater. Additionally, the membrane has good corrosion resistance and hot water resistance, making it suitable for removal of corrosive solutions or hot water in oils.