Rod-like MIL-53(Fe) intercalated MXene nanosheets lamellar composite membrane for the purification of multi-component oily wastewater

Abstract

The complicated oily wastewater containing hazardous organics post a great challenge to the membrane separation technology. Herein, a multilayer porous multifunctional MXene/MOF composite membrane with high permeability and photocatalytic degradation performance was prepared by embedding rod-shaped MIL-53(Fe) into layered MXene nanosheets and self-assembling them onto porous polyacrylonitrile fibrous mat. It was found that the embedment of rod-like MIL-53(Fe) with rough nanostructures could effectively avoid the dense physical stacking of MXene nanosheets and regulate the layer spacing, which was conducive to the enhancement of water channel and permeability of membrane. Moreover, the hydrophilic modification of TA could render the super-wetting feature (WCA=0°, UOCA>150°) and enhance the oil resistance of the membrane. Thence, the composite membrane exhibited favorable separation flux (904.3 ∼ 1226.5 L·m−2·h−1) and retention rate (99.06 ∼ 99.62%) for different O/W emulsions. In addition, the coupling of rod-like MIL-53(Fe) and MXene nanosheets endowed the composite membrane with efficient photocatalytic performance, which could degrade various dyes contained in oily wastewater (CV: 62.4%, MeB: 99.0%, CR: 79.5%, MO: 84.1%). Overall, this study opens up a new way for the preparation of super-wetting and multi-functional fibrous composite membrane, showing the broad application prospects in the purification of multi-component oily wastewater.