Catalytic ceramic nanofiber membrane coupled with ozonation for degradation of sulfamethoxazole: Critical parameters, mechanisms and applicability

• Catalytic ceramic nanofiber membrane was applied for catalytic ozonation of SMX. • Up to 89% of SMX was removed constantly during a 1-h continuous catalytic filtration. • C-CNM coupled with ozonation had high removal efficiency of SMX in real waters. • The presence of Cl - and H 2 PO 4 - inhibited SMX removal while HCO 3 - enhanced removal. • 1 O 2 , ·OH and O 2 ·- were the active species in SMX degradation. Catalytic ceramic nanofiber membrane (C-CNM) filtration coupled with catalytic ozonation process was applied for the removal of sulfamethoxazole (SMX) in various water matrix. The C-CNM was made from attapulgite (APT) nanofibers with Mn 2 O 3 nanoparticles anchored on the pits of APT. Up to 89% of SMX was degraded constantly during a 1-h continuous catalytic filtration with the experimental conditions (water flux = 20 LMH, [SMX] 0 = 20 mg/L, [O 3 (aq) ] inf = 10.5 mg/L). The effects of permeate flux, membrane layer thickness, and the presence of co-existing ions and HA on the degradation efficiency of SMX by C-CNM filtration coupled with catalytic ozonation were studied. The results shows that the degradation of SMX occurred primarily in the membrane layer and the SMX removal increased with smaller fluxes and thicker membrane layer. Besides, the presence of Cl - and H 2 PO 4 - ions obviously inhibited SMX removal while the presence of HCO 3 - slightly enhanced SMX removal. The reactive oxygen species (ROS) that contributed to the removal of SMX were identified to be 1 O 2 , ·OH and O 2 ·- by electron paramagnetic resonance (EPR) analysis and quenching experiments. More importantly, C-CNM/ozone filtration system demonstrated wide applicability for the treatment of a variety of emerging organic contaminants and high removal efficiency of SMX even in real waters. This work promotes the engineering application of catalytic ceramic membrane coupling with advanced oxidation in the decontamination of emerging organic contaminants from water and wastewater.