Sustainable Biomimicked Oil/Water Wettability That Performs Under Severe Challenges

Abstract

In the recent past, biomimicked superliquid repellent interfaces were recognized as the prospective and energy efficient solution for remediation of oil contamination, and mostly two phase oil/water mixtures that are either composed of light oil or heavy oil are demonstrated for gravity driven and environmentally friendly oil/water separation. In reality, the aqueous phase is contaminated with both heavy and light oils. Moreover, the demonstration of common oil/water separation with a two phase system under physically/chemically challenging settings is rare, due to poor durability of the synthesized biomimicked membranes. Here in this report, amine reactive and covalently cross-linked multilayers of chemically reactive polymeric nanocomplex/aminographene oxide nanosheets are adopted for fabricating two distinct durable and tensile deformation tolerant selective-liquid-permeable membranes. Further these biomimicked membranes are exploited in the gravity driven selective filtration of oil and aqueous phase from the three phase oil/water mixture under practically relevant diverse and severely challenging settings, in an unprecedented manner. A prototype was developed through strategic association of both fish scale and lotus leaf inspired stretchable membranes, for simultaneous and active filtration of both heavy/light oils and aqueous phasesfrom their respective mixtures and both the separated oil and aqueous phases were collected in two individual containers. Both the light/heavy oil phases selectively passed through the stretchable superhydrophobic membrane and the aqueous phase filtrated through the underwater superoleophobic membrane. The developed prototype is highly efficient in repetitive (at least 25 times) separation and collection of both oil and water phasessimultaneously, irrespective of density, surface tension, and viscosity of the oil phase and chemical complexity in the aqueous phase