Easy preparation of wood-base membrane with fouling resistance in complex environments for efficient oil-water emulsion separation

Abstract

Abstract Oily wastewater poses a serious threat to the ecological environment and human health, and there is a great deal of concern about how to treat it effectively. Although there has been considerable development in recent years in the treatment of oil-water emulsions using separation membranes with special wettability, they still suffer from real problems such as complex preparation processes, material contamination, so developing an economical and environmentally friendly, high-performance membrane is a significant challenge. In this work, a wood-based membrane was easily prepared by a simple dipping process using aramid nanofiber (ANF) to modify the surface of wood. The wet ANF/wood membrane reveals higher tensile strength (1.69±0.32 MPa) than synthetic hydrogel membranes. More importantly, the membrane presents the underwater superoleophobic properties and fouling resistance under complex environmental conditions (acid, alkali, seawater, and high temperature), and effectively separate various oil-water emulsions with high separation efficiency (>99.3%) and flux (>227 L m-2 h-1). More excitingly, the membrane remains the original separation properties after 13 cycles of oil-water emulsion separation, Therefore, the inexpensive, environmentally friendly and easily prepared ANF/wood membrane is well tolerated under extreme conditions, presents excellent separation performances and provides a material basis for the treatment of actual oily wastewater.