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In this study, a novel CoFe 2 O 4 nanocatalyst impregnated Al 2 O 3 ceramic membrane was prepared via a urea-assisted one-step combustion method. The catalytic membrane was characterized by field emission scanning electron microscopy (FESEM) with energy dispersive X-Ray analysis (EDX) and applied for the catalytic degradation of sulfamethoxazole (SMX) via peroxymonosulfate (PMS) activation under a dead-end membrane filtration mode for the first time. Results indicate that CoFe 2 O 4 could be impregnated into the macropores throughout the whole Al 2 O 3 ceramic membrane via this method and the CoFe 2 O 4 loading amount could be controlled by the multiple impregnation cycles. The membrane filtration operation mode significantly enhances the accessibility of the catalytic active sites to PMS and SMX in microreactor environment and thus the CoFe 2 O 4 impregnated membrane displays excellent catalytic activity for the SMX degradation. The pure water permeability flux can maintain at ∼3000 L m −2  h −1  bar −1 (LMHB) with the catalyst loading amount of 0.015 g/g Al 2 O 3 . In the membrane filtration system, the removal rate of SMX with the initial concentration of 10 mg L −1 can achieve to ∼98%, 70% and 40% with the residence time of 90, 36 and 18 s. The catalytic membrane shows a great tolerance at wide pH range (3–11), the existence of humic acid and anions. Meanwhile, the membrane shows self-cleaning property by retaining >90% of initial flux after 3 treatment cycles. Electron paramagnetic resonance (EPR) and radical quenching experiments indicate that both sulfate radical and hydroxyl radical are generated and sulfate radical is the dominant active species in the process. [ABSTRACT FROM AUTHOR]

A novel Co 3 O 4 nanocatalyst functionalized Al 2 O 3 ceramic membrane (CoFCM) with a honeycomb structure was prepared via an optimized surface-nucleated zeolitic imidazolate framework (ZIF-67) growth method. The Co 3 O 4 hollow structure which was confirmed via chemical characterizations (XRD, FTIR, Raman and XPS), was formed on the membrane surface by one-step calcination of ZIF-67 membrane. The CoFCM was characterized by various techniques including the field emission scanning electron microscopy and atomic force microscopy. The results revealed the formation of well-defined Co 3 O 4 layer on the porous Al 2 O 3 ceramic membrane with the thickness of 1.5–2 µm. The growth mechanism of CoFCM was further proposed via XPS and the catalytic activity of CoFCM was investigated for the removal of sulfamethoxazole (SMX) with the addition of Oxone. The membrane performance was examined under a home-made dead-end mode. Results indicated that CoFCM has a rougher surface with an initial membrane resistance of 1.19 × 10 11  m −1 and performs outstanding catalytic activity. The pure water permeability of CoFCM is 3024 L m −2  h −1  bar −1 , which is comparable to that of the pristine ceramic membrane (<10% difference). The SMX removal efficiency achieved to >90% in 90 min with an Oxone addition of 0.1 g L −1 . Meanwhile, the membrane showed excellent durability by retaining >95% of initial flux for at least 3 operational cycles with a low cobalt ion leaching via Oxone-assisted cleaning. Furthermore, the reaction mechanism of Oxone activation by CoFCM was proposed from the results of the electron paramagnetic resonance (EPR) and radical scavenger experiments. [ABSTRACT FROM AUTHOR]

A novel mesoporous graphitic carbon nitride/titanium dioxide (mpg-C 3 N 4 /TiO 2 ) nanocomposite was successfully synthesized and incorporated into polysulfone (PSf) matrix to fabricate photocatalytic membranes. This study aimed to explore the photocatalytic ability of the novel nanomaterial membrane in degrading the antibiotic sulfamethoxazole (SMX) under solar light. The structural and morphological properties of the mpg-C 3 N 4 /TiO 2 nanocomposite and membrane were characterized using various techniques. The SMX photocatalytic degradation performance, pathway and mechanism by mpg-C 3 N 4 /TiO 2 photocatalytic membrane reactor (PMR) were systematically investigated using HPLC and LC-MS/MS. As a pharmaceutically active compound, SMX was transformed into 7 kinds of non-toxic and pharmaceutically inactive byproducts by the innovative PMR technology. SMX removal efficiency of the membrane PSf-3 (with 1% mpg-C 3 N 4 /TiO 2 loading) was the highest over the 30 h consecutive irradiation. Meantime, the membrane didn’t affect the SMX photodegradation, and the structure was able to provide stable support with high integrity and flexibility after solar irradiation. The developed membrane has a great potential to be applied in water treatment industry. [ABSTRACT FROM AUTHOR]