Bio-Inspired Underwater Superoleophobic Aramid Nanofiber-Based Aerogel Membranes for Highly Efficient Removal of Emulsified Oils and Organic Dyes.

Abstract

Effective elimination of insoluble emulsified oils and soluble organic dyes has received extensively attention in wastewater treatment. In this work, a chitosan and polydopamine @ aramid nanofibers (CS&PDA@ANFs) aerogel membrane was fabricated through an integration methodology consisting of phase inversion and successive deposition of PDA and CS. The as-prepared aerogel membrane possessed a satisfactory three-dimensional interpenetrating network architecture with high porosity and desirable mechanical property. Furthermore, due to the synergistic effect of hydrophilic CS and PDA, the resultant membrane exhibited good superhydrophilicity and underwater superoleophobicity associated with favorable oil resistance/antioil fouling properties. The combination of the interconnected porous structures and super wettability endowed the aerogel membranes with desirable oil-in-water emulsion separation performance. Particularly, an extremely high permeation flux (3729 L/m2/h) and a rejection rate (99.3%) were achieved for the CS&PDA@ANFs membrane. Moreover, diverse dyes could be also adsorbed by the resultant membrane, and the equilibrium adsorption capacity of cationic dye malachite green could reach 36 mg/g, with a high rejection rate over 97%. This study indicated that the CS&PDA@ANFs aerogel membrane held great promise for practical applications in complex wastewater remediation.