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A composite of cobalt tetracarboxyl phthalocyanine and amino-functionalized manganese octahedral molecular sieve (CNOMS-2) was synthesized in a simple way, and applied for degrading diclofenac in aqueous media by catalyzing of peroxymonosulfate heterogeneously. The experiment results revealed that the CNOMS-2/PMS system was highly efficient for DCF degradation in the pH range of 5-9, and the mechanism involved the generation of OH, SO4⁻ and 1O2 by the activation of PMS. The main reactive oxygen species was found to be 1O2 by radical scavenging experiments and electron paramagnetic resonance (EPR) spectroscopy. Further, a carboxylation product of DCF at m/z 340 was found to be a prominent intermediate of the reaction in this system specially, as determined by LC-MS/MS. The reusability and ion leaching concentrations under different pH were also examined to determine the application prospects of the catalyst.

Manganese oxide octahedral molecular sieve (OMS-2) and a series of OMS-2 doped with Co, Cu, and Ce were prepared via a solvent-free method, and tested in heterogeneous activation of peroxymonosulfate (PMS) for diclofenac (DCF) degradation in aqueous solutions. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), N2 adsorption/desorption isotherms, Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and X-ray photoelectron spectroscopy (XPS) were used to characterize the properties of those materials. It was found that (Co + Ce)-OMS-2 seemed to be most efficient and had the best adsorption capacity, which may due to most abundant lattice oxygen and more macropore than other materials caused by cerium ions enter into the channel. Results from XPS suggested that the highly catalytic efficiency possible involved the activation of PMS to sulfate and hydroxyl radical meditated by the redox pair of Mn(IV)/Mn(III) and Co(III)/Co(II) in catalysts. Keywords: Manganese oxide octahedral molecular sieve, Diclofenac, Peroxymonosulfate

A facile three-step photo-deposition method was applied to successfully synthesize Ag and AgI modified ZnO composites (AgI/Ag/ZnO). Under visible-light irradiation, the composites enhanced the photocatalytic efficiency of Naproxen (NPX) degradation as the Ag contents increased. 100 % NPX could be removed in 60 min when AgI/Ag/ZnO (75 %) was the catalyst. Different initial pH, alongside the addition of NO3− and SO42− had little impact, but Cl− could accelerate the degradation rate. O2− and h+ played a significant role in the photocatalysis process. Several byproducts were predicted by DFT-software calculation and verified by LC–MS/MS. The cycling experiments showed that the removal rate decreased after the first run due to the leaching of Ag+. The removal rate kept stable after the next two reactions.

Diclofenac (DCF) control measures have become an area of increased interest for environmental researchers due to the high environmental concentration and risk of DCF. Adsorption seems to be promising for DCF removal from the aqueous phase because of its specific superiority in comparison with biodegradation, membrane separation, and advanced oxidation or reduction. In this study, OMS-2 and metal-doped OMS-2 ((Me-OMS-2, with Me = Co, Cu or Ce) were prepared and tested as adsorbents for the removal of DCF. It was evident that the maximum adsorption capacity and rate of Ce-OMS-2 were much higher than those of the other adsorbents, which could be attributed to its large specific surface area and stereoscopic aperture structure. The experimental data are fitted the pseudo-second-order model, the Elovich equation and the Langmuir model well; moreover, the process is an endothermic and spontaneous thermodynamic process, during which the entropy increased, based on the experimental results, indicating that chemisorption was dominant during the DCF adsorption process onto Ce-OMS-2. By the integral of the peak deconvoluted from the XPS spectrum, the ratio of Mn3+/Mn4+ increased from 0.393 to 0.407, revealing that Mn(IV) is rarely reduced into Mn(III) during the DCF adsorption process.