Superhydrophilic ZIF ‐8@ PMIA Nanofibrous Membrane With Demulsification Property for Efficient Separation of Oil‐in‐Water Emulsions

ABSTRACT

Nanofibrous membranes have great potential for treating oily wastewater. However, the random stacking of nanofibers during the electrospinning process resulted in a broad pore size distribution and reduced separation efficiency. Moreover, for oil‐in‐water emulsions stabilized by ionic surfactants, the small oil droplets deform under the applied pressure and are squeezed into the membrane pores, leading to a decrease in flux and fouling. In this work, we developed superhydrophilic nanofibrous membranes with demulsification properties via electrospinning and a solvothermal seed‐induced method. Notably, the incorporation of ZIF‐8 nanoparticles offers multiple advantages, such as reducing membrane pore size, increasing the surface roughness, and enhancing membrane surface charge. These features synergistically improve both separation selectivity and demulsification properties. As a result, the membrane exhibits outstanding separation performance, achieving a separation efficiency of 96.37% for diesel‐in‐water emulsions and a high permeation flux of 4100 L m ⁻²  h ⁻¹ for dichloromethane‐in‐water systems. This work provides an effective strategy for developing high‐performance membranes for oil‐in‐water emulsions separation applications.