Facile and Green Fabrication of Superhydrophobic Polyacrylonitrile Nonwoven Fabric with Iron Hydroxide Nanoparticles for Efficient Oil/Water Separation

Superhydrophobic materials have been used for the treatment of oily wastewater due to their selective absorption properties. However, many of the reported methods for creating superhydrophobic surfaces lack the feasibility for large-scale production due to the use of non-environmentally friendly chemicals or the involvement of complicated fabrication steps. In this study, we report a simple, green, and rapid process for fabricating superhydrophobic polyacrylonitrile (PAN) nonwoven fabric (NWF) for the separation of oil/water mixtures via adsorption and filtration strategies. PAN NWF was functionalized with iron hydroxide nanoparticles, which endowed the modified fabric with increased surface roughness and hydrophobic property. In the next step, the superhydrophobicity was attained by creating a multiscale hierarchical surface roughness and lowering the surface energy via an in situ deposition of the iron palmitate complex nano/microparticles. The resulting superhydrophobic PAN NWF exhibited high chemical stability in corrosive environments and excellent mechanical durability as revealed from the sandpaper abrasion and tape peeling tests. The superhydrophobic NWF showed good oil absorption capacity, high permeation flux, high separation efficiency, and stable performance for 20 separation cycles. The excellent durability, recyclability, and long-term separation performance are expected to enable the application of the modified fabric for water-oil separation in harsh environments.