Polymer-Decorated Filter Material for Wastewater Treatment: In Situ Ultrafast Oil/Water Emulsion Separation and Azo Dye Adsorption.

Aiming to realize the wastewater treatment of various pollutants simultaneously, a dual-functional poly(ether amine)-polydopamine (PEA-PDA)-modified filter material was fabricated in this work for in situ separation of stable oil-in-water emulsion and adsorption of anionic azo dyes. PEA and PDA could be copolymerized via the Michael addition reaction on a polyurethane sponge substrate firmly. The as-prepared filter shows superhydrophilic and underwater superoleophobic wettability. After being squeezed in a glass tube, the material could separate different kinds of stabilized oil-in-water emulsions with high flux and efficiency. Besides, the PEA-PDA copolymer endows the material with the ability to adsorb large amounts of anionic azo dyes during the separation of emulsions with good adsorption capacity. Moreover, adsorbed dyes in the filter material could be easily desorbed in base aqueous solution and the whole process is conducted under gravity without external aid. This dual-functional material shows great potential for the application in industrial field because of its ability for the complex wastewater treatment.