MIL-88A-based Antifouling Superhydrophilic Membrane for Efficient Emulsion Separation and Dye Degradation via Photo-Fenton Process

Abstract

Pollution of oily wastewater is a serious worldwide environmental problem that causes serious harm to the environment and human beings, while at the same time, emulsifier and dye wastewaters pose great difficulties for wastewater treatment. In a previous study, MIL-88A as an iron-based metal-organic frameworks (MOFs) has good hydrophilicity and large specific surface area, in addition, it acts as a Fenton catalyst, generating strong oxidizing hydroxyl radicals under the condition of UV light and hydrogen peroxide to achieve efficient degradation of dyes. Inspired by this, we prepared nano-needle zinc oxide on stainless steel mesh (SSM) by electrochemical method, and then prepared MIL-88A-based superhydrophilic membranes by spraying method, which can easily separate a variety of oil-in-water emulsions. After 10 emulsion separations, the separation efficiency of the prepared membrane was still as high as 99.5 %. In addition, the prepared membranes have a high removal rate of methylene blue (MB), degrading 98 % of MB in 35 min, and remain underwater superoleophobic even after 50 cycles of sandpaper abrasion. This robust mesh for efficient emulsion separation and dye removal shows great potential for oily wastewater treatment and water quality remediation.