Peroxymonosulfate Activation For Degradation Research Articles

Non-radical activation of peroxymonosulfate for degradation of antibiotics in saline environments by biochar flakes prepared with molten salt strategy

Due to the serious interference of inorganic salts, it is very important to develop a peroxymonosulfate (PMS) oxidation system that can operate normally and efficiently in saline environments. Herein, the Fe-N-doped biochar flakes (FSBC) derived from sesame powder were developed with the help of molten salt strategy for activating PMS to achieve efficient degradation of tetracycline in salt environment. The effect of calcination temperature on physical and chemical properties was studied to further optimize the performance of the catalyst. FSBC-800 showed the best activation performance for PMS, with a TC removal rate of ∼ 94 % within 10 min. Mechanism research shows that FSBC-800 activates PMS through singlet oxygen (1O2) and electron transfer, so the reaction system is extremely selective and can almost avoid interference from various inorganic ions. The FSBC-800/PMS system can operate efficiently in the coexistence of 8 common anions/cations (0–250 mM), and salinity of 0.1–5.0 wt% has almost no negative impact on the system. In addition, possible degradation pathways of tetracycline were proposed, and the toxicity of intermediate products during the degradation process was evaluated. This study provides a PMS oxidation system with strong selectivity that can cope with various complex saline environments.

Cyclotriphosphazene (P3N3) derived FeOx@SPNO-C core–shell nanospheres as peroxymonosulfate activator for degradation via non-radical pathway

Though synergistic interactions between quaternary heteroatom (S, N, P, O) and FexO atoms could significantly improve catalytic performance, however, developing a robust catalyst with quaternary heteroatom-doped carbons and FexO is rarely addressed. We fabricated FeOx@SPNO-C core–shell nanospheres by using cyclotriphosphazene (P3N3)-derived covalent organic–inorganic hybrid frameworks (COIFs) and Fe3O4. The as-synthesized FeOx@SPNO-C nanospheres catalyst attained superior PMS activation for degradation of sulfamethoxazole (SMX), achieving 99.5 % removal efficiency in 18 min, 65.1 % mineralization rate, lower iron leaching (0.014 mg/L), and reaction rate constant was 73.6 % higher than sole SPNO-C, counterpart. Non-radical 1O2 generation was the dominant pathway for SMX degradation, which was confirmed by electron paramagnetic resonance (EPR), radical quenching inorganic ions addition experiments, and density functional theory (DFT) calculations. Structural defects, C = O, C = C–C groups, and N/Fe-Nx sites atoms have been revealed to be active sites. The improved degradation of SMX may be attributed to many essential characteristics. Firstly, there is a synergistic impact between FexO and SPNO-C. Additionally, the carbon charge density is high, and there are numerous structural defects present. Furthermore, there is a significant presence of C = O groups, with a higher proportion of sp2 carbon containing sufficient free-flowing π electrons. Lastly, the presence of N/Fe-Nx sites also contributes to the enhanced degradation of SMX. Several intermediate products were found, and a potential degradation mechanism was postulated. The high performance of FeOx@SPNO-C under harsh experimental conditions makes it a potential candidate for the commercial-scale Fenton-like catalyst.

A Co@C Catalyst Derived from a Cobalt‐Based Metal Organic Framework with Enhanced Activation of Peroxymonosulfate for Degradation of Organic Pollutants

AbstractCobalt‐based catalysts are widely used as efficient activator for the activation of peroxymonosulfate (PMS). A new carbon enclosed magnetic metal cobalt (Co@C) catalyst was successfully synthesized by high‐temperature pyrolysis of cobalt‐based metal‐organic framework. The prepared Co@C catalyst demonstrated remarkable catalytic activity for the degradation of contaminants (99.9 % for tetracycline (TC) degradation within 10 min). The TC degradation efficiency could still sustain more than 99 % after three cycles. Moreover, the Co@C/PMS system exhibited great universality for the rapid removal of other dyes such as methyl orange (MO) and methylene blue (MB). The zero‐valent cobalt was engaged in the activation of the PMS and reacted with O2 to form Co2+, to make sure that there was enough Co2+ to activate PMS to generate Co3+. Simultaneously, the produced Co3+ ions extracted electrons out of , driving a Co0/Co2+/Co3+ circulation to keep the high efficiency for rapid degradation of TC. In summary, this work offers a novel strategy to develop an effective magnetic heterogeneous catalyst to activate PMS for the elimination of difficult to degrade contaminants.

Activation of peroxymonosulfate for degradation of norfloxacin by Mn-doped zeolitic imidazolate framework-67 nanocrystals

The figure shows the possible mechanism of the degradation process and the removal and mineralization rates.

Co3O4/carbon felt three‐dimensional electrode promoted electrocatalytic oxidation – peroxymonosulfate system for p‐nitrophenol degradation: effect of radical and non‐radical mechanisms

AbstractBACKGROUNDConventional electrochemical oxidation (EO) processes do not easily activate peroxymonosulfate (PMS) and are susceptible to the effects of electrode size, material and large‐distance two‐dimensional (2D) electrode structures, resulting in low mass transfer efficiency and low electrolytic productivity, limiting their ability to degrade pollutants. It is still a challenge to design and prepare a system and materials to enhance the activation of PMS and the EO process.RESULTSCo3O4‐loaded carbon felt three‐dimensional (3D) electrode material (Co/CF) was prepared and used to construct a 3D electrocatalytic synergistic system (EO‐Co/CF‐PMS). The system combined the advantages of bipolar electrochemistry, three‐dimensional electrochemistry and advanced oxidation processes based on sulfate radical (SR‐AOPs) to facilitate the activation of PMS for degradation of p‐nitrophenol (PNP) in water. In addition, the synergistic system showed excellent pollutant degradation performance, achieving 89.51% PNP degradation in 10 min with an energy consumption of 0.4255 kWh m−3. After being used for four consecutive cycle experiments, the synergistic system still achieved 83% PNP removal. Besides, the EO process also facilitated the Co cycle, resulting in a continuous and efficient degradation of the pollutants. The effects of experimental parameters (initial pH, PMS dose, and applied voltage) on PNP elimination were determined. The results of a reactive oxygen species scavenging experiment and electron spin resonance analysis showed that ·OH, SO4·−, and 1O2 all played a major role in the PNP elimination process.CONCLUSIONSThe research demonstrated that the composite catalyst Co/CF improved the property of the EO process for catalyzing PMS and thus enlarged the practical application of AOPs in pollutant degradation in aqueous solution. © 2022 Society of Chemical Industry (SCI).

Evaluation of efficiency of copper-nickel ferrite nanoparticles loaded onto multi-walled carbon nanotubes in activation of peroxymonosulfate for degradation of reactive black dye 5 from aqueous solutions

Evaluation of efficiency of copper-nickel ferrite nanoparticles loaded onto multi-walled carbon nanotubes in activation of peroxymonosulfate for degradation of reactive black dye 5 from aqueous solutions

Synergistic oxygen vacancy-rich CuO/visible light activation of peroxymonosulfate for degradation of rhodamine B: fast catalyst synthesis and degradation mechanism.

This work outlines the synthesis of copper oxide nanoparticles (CuO-SC) loaded with a number of oxygen vacancies by a fast sodium citrate assisted precipitation method with no need of calcination. X-ray diffraction, scanning electron microscopy, UV-Vis diffuse reflectance spectroscopy, time-resolved fluorescence lifetime and electrochemical impedance spectra were used to characterize the as-synthesized nanocomposites. The results indicated that the CuO-SC nanoparticles had regular fusiform shape with high surface area, wide light harvesting window, fast charge transport and high carrier concentration. As a result, the catalytic activity of the CuO-SC/peroxymonosulfate (PMS)/visible light (Vis) system for the degradation of rhodamine B (RhB) was much higher than that of as-prepared CuO nano powder in the absence of sodium citrate. Almost 98.0% of the initial RhB dyes was decomposed in 20 min with 0.12 g L−1 PMS and 0.3 g L−1 catalyst. Meantime, it exhibited high catalytic stability with little deactivation after four runs and a wide application range of pH. Moreover, RhB can be readily degraded with backgrounds of Cl−, NO3−, SO42−, HCO3− and low concentration of humic acid in a CuO-SC/PMS/Vis system. Combined with the results of electron spin resonance paramagnetic spectroscopy, X-ray photoelectron spectroscopy and radical quenching experiments, holes, superoxide radicals and a small amount of sulfate radicals, hydroxyl radicals and singlet oxygen were involved in the CuO-SC/PMS/Vis system. Furthermore, a possible degradation mechanism based on the synergistic effect of radical reaction and non-radical reaction was proposed based on the above results.

Mofs-Derived Magnetic Hollow Feco@C as Peroxymonosulfate Activator for Degradation of Organic Pollutants: Experimental and Theoretical Study

Mofs-Derived Magnetic Hollow Feco@C as Peroxymonosulfate Activator for Degradation of Organic Pollutants: Experimental and Theoretical Study

Core-Shell Magnetic Cfo@Cof Composites Toward Peroxymonosulfate Activation for Degradation of Sulfamethoxazole from Aqueous Solution: Radical Pathway and Non-Radical Pathway

Core-Shell Magnetic Cfo@Cof Composites Toward Peroxymonosulfate Activation for Degradation of Sulfamethoxazole from Aqueous Solution: Radical Pathway and Non-Radical Pathway

Dual functional cobalt-yttrium binary oxide activation of peroxymonosulfate for degradation of phenylphosphonic acid and simultaneous adsorption of phosphate product

Cobalt-yttrium binary oxide (CYBO) was successfully fabricated, which exhibited excellent catalytic performance in the activation of peroxymonosulfate (PMS) and superior adsorption capacity towards phosphate (116.3 mg-P/g). The results demonstrated that a complete degradation of phenylphosphonic acid (PPOA) within 30 min and a thorough removal of phosphate product within 60 min could be realized in the system of CYBO/PMS. CYBO also possessed superb reusability and stability, and no decline of the PPOA degradation and phosphate removal was observed during 5 cycles at initial pH 7. The decomposition of PPOA and the adsorption of phosphate were strongly dependent on solution pH. In an initial pH range of 3 to 7, both PPOA and phosphate product could be efficiently removed. However, almost no PPOA was degraded at initial pH 11. SO4•−, •OH, and 1O2 (especially SO4•− and •OH) were identified as main reactive oxygen species responsible for the PPOA degradation and the formation of phosphate product. The produced phosphate was simultaneously eliminated via anion/ligand exchange. Combined with identification of PPOA degradation intermediates via HPLC-QTOF-MS2, the calculation of frontier electron densities based on Density Functional Theory was used for proposing reasonable degradation pathways. In addition, the toxicity assessment via Toxicity Estimation Software Tool was utilized to appraise eco-environmental effect. Our findings may shed some light towards the application of CYBO in the control of organophosphorus pollution and the reduction of water eutrophication.

Architecturing CoTiO3 overlayer on nanosheets-assembled hierarchical TiO2 nanospheres as a highly active and robust catalyst for peroxymonosulfate activation and metronidazole degradation

• CoTiO 3 overlayer was formed on nanosheets-assembled hierarchical TiO 2 nanospheres. • Cobalt sites of CoTiO 3 /TiO 2 showed a better activation ability than those of Co 3 O 4 . • CoTiO 3 /TiO 2 was highly efficient in catalytic degradation of metronidazole. • Plausible degradation pathways and catalytic mechanism were elucidated. • Low cobalt leaching and excellent reusability were also achieved. Catalytic performance of a heterogeneous cobalt-based catalyst for advanced oxidative process (AOP) correlates tightly with its structure and composition. The main objective of this study is to maximize the utilization and accessibility of cobalt sites while enhancing their activity and stability through rational structural and composition designs, and thus to achieve an excellent performance for heterogeneous peroxymonosulfate (PMS) activation. To this end, a novel CoTiO 3 /TiO 2 composite (CTT), composed of CoTiO 3 overlayer on nanosheets-assembled hierarchical TiO 2 nanospheres, was elaborately designed and synthesized. The resulting CTT possessed certain features including CoTiO 3 -rich surface, large surface area (114.8 m 2 g −1 ), and highly open porous channels, which afforded sufficient accessible active sites against undesirable particle agglomeration and shedding. Moreover, cobalt sites of CTT exhibited a higher activity toward PMS than those of Co 3 O 4 due to the composition-induced distinct adsorption nature, easy electron transfer, and strong bond-weakening ability. Benefitting from the unique combination of structural and compositional advantages, CTT manifested remarkable catalytic efficiency, low cobalt leaching (0.078 mg L −1 ), and excellent reusability in activation of PMS for degradation of the emerging antibiotic pollutant metronidazole (MNZ). The potential degradation pathway for MNZ and the catalytic mechanism were further elucidated. The design strategy proposed in this study may provide a new opportunity for future development of high-performance heterogeneous cobalt-based catalysts in remediation of aquatic environment.

Biomass-derived functional porous carbons for adsorption and catalytic degradation of binary micropollutants in water

The biomass, bottlebrush flower, is exploited for the preparation of functionalized porous carbons by one-pot thermal activation using NaHCO3 and dicyandiamide. An intensified cross-linking effect among the precursors boosts pore (especially mesopore) formation in the pyrolysis process, producing N-doped porous carbons (NPCs) with a large specific surface area (SSA, up to 2025 m2 g−1). The biomass-derived carbon samples turn out to be highly effective in adsorption, and catalytic activation of peroxymonosulfate for degradation of aqueous phenol and p-hydroxybenzoic acid (HBA) in single and binary systems. The effects of N content, porous structure, and trace Ni species on the adsorptive and catalytic behavior of carbon are investigated. It is found that the porous structure plays a more critical role in adsorption than surface N functionality, while the contributions of various reactive species for phenol and HBA degradation are different.

Effect of calcination temperature on the catalytic performance of CoFe2O4/Nitrogen doped sludge based activated carbon in activation of peroxymonosulfate for degradation of coking wastewater

A novel supported heterogeneous magnetic catalyst CoFe2O4/N-doped sludge based activated carbon (CoFe2O4/N-SAC) was prepared by polymer network gel method for the first time. The physicochemical properties of the materials were characterized by means of XRD, SEM, TEM, VSM and XPS techniques. The prepared catalyst is applied to the heterogeneous activation of peroxymonosulfate for degradation of coking wastewater, and the effect of calcination temperature on the catalytic activity was investigated. The result reveals that the catalyst shows the highest catalytic activities under the calcination temperature is 800 °C with the TOC removal rate of coking wastewater is 84.31%.

A heterogeneous Co3O4–Bi2O3 composite catalyst for oxidative degradation of organic pollutants in the presence of peroxymonosulfate

By using cobalt nitrate and bismuth nitrate as precursor salts and NaOH as a precipitation agent, Co3O4–Bi2O3 nanocomposite oxides (CBO) were prepared as a heterogeneous catalyst for the activation of peroxymonosulfate (PMS) by a conventional reverse co-precipitation method and post-calcination. The characterization with transmission electron microscopy, X-ray diffractometry, X-ray photoelectron spectroscopy and Raman spectroscopy demonstrated that there was a strong interaction between Bi and Co components in CBO. The presence of Bi increased the content of surface hydroxyl oxygen, which favored the formation of Co(II)–OH complexes that were vital for heterogeneous activation of PMS. CBO showed strong catalytic activity in the heterogeneous activation of PMS for degradation of organic pollutants such as methylene blue (MB), rhodamine B, phenol and 2,4-dichlorophenol. With the addition of 0.5 mmol L−1 PMS, CBO produced fast and full degradation of MB (20 μmol L−1) with the apparent rate constant of 0.36 min−1, being 8.6 fold of that (0.042 min−1) over nano-Co3O4. It decreased the cobalt leaching to 43 μg L−1, being much less than that (158 μg L−1) from Co3O4 under the same conditions. The effects of CBO loading, PMS concentration and calcination temperature on the degradation of MB and cobalt leaching were also investigated.