Synchronously improved permeability, selectivity and fouling resistance of Fe-N-C functionalized ceramic catalytic membrane for effective water treatment: The critical role of Fe

Constructing catalytic membrane simultaneously displaying high permeability, selectivity and antifouling performance in water treatment remains challenging. Herein, the surface and pore channels of the ceramic membrane were co-functionalized with nitrogen doped carbon supported Fe catalyst (CN-F), and the Fe content was varied to investigate its effect on performance of CN-F coupled with peroxymonosulfate (PMS) activation (CN-F/PMS) for water treatment. Results confirmed the introduced Fe (in Fe-N coordination form) greatly enhanced the permeability, selectivity and fouling resistance of CN-F. Optimal CN-F3/PMS achieved 96.5% removal and 52.1% mineralization of sulfamethoxazole in short retention duration (2.7 min), whose performance was 5.4 and 6.7 times higher than that of nitrogen doped carbon functionalized ceramic catalytic membrane (CN/PMS) and CN-F3 filtration alone, respectively. CN-F3/PMS also efficiently inhibited fouling on both surface and pores with 2.8 and 2.4 times lower flux loss than that of CN/PMS and CN-F3 filtration alone, respectively. Moreover, CN-F3/PMS displayed superior performance in long-term treatment of real coking wastewater. The outstanding performance of CN-F was mainly attributed to the dual role of supported Fe, which served as hydrophilic site for enhanced water permeation and major active site for PMS adsorption and reduction into reactive species (mainly high-valent Fe(IV)=O species) towards pollutant elimination. Constructing catalytic membrane with high permeability, selectivity and antifouling capability for water treatment is highly desirable but remains challenging. Herein, a novel ceramic catalytic membrane with surface and pores co-functionalized with Fe-N-C catalyst (CN-F) was prepared and integrated with peroxymonosulfate (PMS) activation for water decontamination. The Fe played dual role in simultaneously enhancing permeability, selectivity and antifouling capability of catalytic membrane, which realized rapid removal and mineralization of various hazardous organic chemicals and fouling mitigation on both membrane surface and pores. Moreover, owing to high-valent Fe(IV)=O species dominated non-radical mechanism, catalytic membrane displayed superior performance in long-term real wastewater treatment.