High-flux robust ceramic membranes functionally decorated with nano-catalyst for emerging micro-pollutant removal from water

Abstract

Highly efficient water treatment is an important challenging issue for membrane separation where high flux, high removal rate, low fouling under low or even zero energy consumption are highly emphasized. In the present work, high-flux hierarchically structured ceramic membranes functionally decorated with active CoFe2O4 nano-catalyst was rationally designed and applied in highly efficient removal of emerging organic micro-pollutants from water. Coupling with sulfate radicals-advanced oxidation processes (SR-AOPs), such composite membranes could be operated with highly stable flux without any extra energy consumption, only under the gravity of the feeds, which is much more energy-efficient than traditional counterparts. After detailed structure characterizations, the performance such as flux, removal rate and stability were fully assessed. High flux can be attributed to the specially designed membrane structure with long finger-like macroporous layers featuring rapid transport, significantly outperforming other reported state-of-the-art separation membranes. High removal rate can be ascribed to a sponge-like layer loaded with nano-catalysts as micro-reactors for sufficient degradation of organic micro-pollutants. Mechanism analysis indicates that SO4•− is a dominant active radical responsible for catalytic degradation while physical adsorption played a minor effect. This technology is expected to be of potential for application in remote areas where power energy is absent, or simply used as a point-of-use technology in decentralized water treatment.