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The magnetic CuFeO2anchored on nitrogen-doped porous carbon (CuFeO2/NC) hybrid catalysts were further synthesized via hydrothermal reaction without the addition of a chemical reductant. The systematic CuFeO2/NC with larger specific surface areas (SSAs) and abundant active sites exhibited strong adsorption ability and great catalytic performance towards activating peroxymonosulfate (PMS) for sulfamethoxazole (SMX) removal. It was noted that 18 mg/L SMX was completely removed after 40 min of pre-adsorption and 30 min of oxidative degradation in CuFeO2/NC and PMS system. The degradation rate constant (k) was calculated by fitting as 0.166 min−1, being about 7.9 times that in the CuFeO2and PMS system (0.021 min−1). The SO4·-,·OH, and 1O2as the dominant reactive oxygen species (ROSs) contributed to sulfamethoxazole degradation. The N species, active oxygen and the redox cycles of Cu(Ⅱ)/Cu(Ⅰ) and Fe(Ⅲ)/Fe(Ⅱ) were confirmed to play a vital role in the activation of PMS for the generation of ROSs. Based on the LC-MS analysis, the possible degradation routes of SMX in the PMS activation system by CuFeO2/NC were proposed.

Electrospun nanofiber membranes are ubiquitous in the ecological environment due to the high specific surface area and porosity, excellent functionality and recycling. Surface enriched ZIF-67 that incorporated into electrospun rice straw-derived cellulose acetate (RSCA) nanofibers mats were synthesized using a facile in-situ growth strategy. The RSCA was achieved by the acetylation reaction of rice straw-derived cellulose, which was extracted from the recycled waste agricultural rice straw by green solvent. The structures and properties of ZIF-67/RSCA were investigated to reveal the mechanism of in-situ growth method. ZIF-67/RSCA mat shows efficient CO2capture and water treatment performance. The achieved ZIF-67/RSCA-0.1 M nanofiber membrane possesses optimal capacities for CO2(1.33 mmol/g at 273 K and 101 kPa), which reached to 70% of ZIF-67 powders. MO adsorption capacity of ZIF-67/RSCA-0.1 M membrane was matched with the pseudo-second-order kinetic model, and their equilibrium adsorption capacity towards MO was found to be 11.20 mg/g at room temperature, which is about 15 times as that of pure RSCA nanofibers membrane (0.77 mg/g). Moreover, the ZIF-67/RSCA could selectively adsorb the MO, while it cannot remove the MB pollutant. The detailed analysis of BET and Zeta potential indicated that larger specific surface area and positive potential of ZIF-67/RSCA were favorable for efficient adsorption and selectivity. We believe the approach to fabricate ZIF-67/RSCA nanofibers membrane using the rice straw for removing CO2and MO is a win-win strategy for the application of agricultural waste to environmental pollution.