Facile Fabrication of Superhydrophobic Cellulose Film with Enhanced Abrasion and Corrosion Resistance for High-Flux Oil-Water Separation

Abstract

A durable and environmentally friendly superhydrophobic cellulose-based membrane, denoted as FP/PDA@MCC/OTS (where FP, PDA, MCC, and OTS represent filter paper, polydopamine, microcrystalline cellulose, and octadecyltrichlorosilane, respectively), was fabricated via a simple PDA toughening and OTS-modified MCC coating strategy. Cellulose filter paper was first reinforced with a PDA interfacial layer to enhance mechanical stability, adhesion, and chemical resistance. Subsequently, hydrophobic MCC particles grafted with OTS were spray-deposited, forming a hierarchical fiber-particle composite structure. The resulting membrane exhibits a stable superhydrophobic surface with a water contact angle (WCA) above 150°, attributed to the synergistic effect of hierarchical roughness and low-surface-energy modification. It achieves high oil-water separation efficiency (>98%, up to 99.99%) and a high flux of up to 2.3 × 104 L·m−2·h−1 under gravity-driven conditions. Moreover, the membrane maintains excellent performance stability after repeated abrasion, ultrasonic treatment, and long-term acid/alkali immersion, with WCA remaining above 136°. The enhanced durability is attributed to robust interfacial interactions provided by PDA and stable surface anchoring of OTS-derived silane species on cellulose. This work provides a simple, scalable, and sustainable strategy for constructing robust cellulose-based membranes for efficient oily wastewater treatment under harsh conditions.