Advanced oxidation processes (AOPs), defined as those technologies that utilize the hydroxyl radical (·OH) for oxidation, have received increasing attention in the research and development of wastewater treatment technologies in the last decades. These processes have been applied successfully for the removal or degradation of toxic pollutants or used as pretreatment to convert recalcitrant pollutants into biodegradable compounds that can then be treated by conventional biological methods. The efficacy of AOPs depends on the generation of reactive free radicals, the most important of which is the hydroxyl radical (·OH). The authors summarize the formation reactions of ·OH and the mechanisms of pollutants degradation. They cover six types of advanced oxidation processes, including radiation, photolysis and photocatalysis, sonolysis, electrochemical oxidation technologies, Fenton-based reactions, and ozone-based processes. Controversial issues in pollutants degradation mechanism were discussed. They review t...

Advanced Oxidation Processes for Wastewater Treatment: Formation of Hydroxyl Radical and Application

Magnetic nanoscaled Fe3O4/CeO2 composite was prepared by the impregnation method and characterized as a heterogeneous Fenton-like catalyst for 4-chlorophenol (4-CP) degradation. The catalytic activity was evaluated in view of the effects of various processes, pH value, catalyst addition, hydrogen peroxide (H2O2) concentration, and temperature, and the pseudo-first-order kinetic constant of 0.11 min–1 was obtained for 4-CP degradation at 30 °C and pH 3.0 with 30 mM H2O2, 2.0 g L–1 Fe3O4/CeO2, and 0.78 mM 4-CP. The high utilization efficiency of H2O2, calculated as 79.2%, showed a promising application of the catalyst in the oxidative degradation of organic pollutants. The reusability of Fe3O4/CeO2 composite was also investigated after six successive runs. On the basis of the results of metal leaching, the effects of radical scavengers, intermediates determination, and X-ray photoelectron spectroscopic (XPS) analysis, the dissolution of Fe3O4 facilitated by CeO2 played a significant role, and 4-CP was decom...

Magnetic Nanoscaled Fe3O4/CeO2 Composite as an Efficient Fenton-Like Heterogeneous Catalyst for Degradation of 4-Chlorophenol

Trends in electro-Fenton process for water and wastewater treatment: An overview

CuFe 2 O 4 magnetic nanoparticles (MNPs) were prepared by sol–gel combustion method with copper and iron nitrates as metal precursors and citrate acid as a complex agent. The obtained CuFe 2 O 4 MNPs were characterized by scanning electron microscopy, X-ray diffractometry, Fourier transform infrared spectroscopy, Fourier transform Raman spectroscopy and X-ray photoelectron spectroscopy. It was found that CuFe 2 O 4 MNPs could effectively catalyze peroxymonosulfate (PMS) to generate sulfate radicals (SO 4 − ) to degrade tetrabromobisphenol A (TBBPA). The added TBBPA (10 mg L −1 ) was almost completely removed (with a removal of 99%) in 30 min by using 0.1 g L −1 CuFe 2 O 4 MNPs and 0.2 mmol L −1 PMS. With higher addition of PMS (1.5 mmol L −1 ), the degradation yielded a TOC removal of 56% and a TBBPA debromination ratio of 67%. The effect of catalyst calcination temperature, catalyst load, PMS concentration and reaction temperature was investigated on the catalytic activity of CuFe 2 O 4 MNPs. The highly catalytic activity of CuFe 2 O 4 MNPs possibly involved the activation of PMS by both Cu(II) and Fe(III) in CuFe 2 O 4 MNPs. Based on intermediate detections, the degradation pathway of TBBPA in the CuFe 2 O 4 MNPs/PMS system was proposed.

Sulfate radicals induced degradation of tetrabromobisphenol A with nanoscaled magnetic CuFe2O4 as a heterogeneous catalyst of peroxymonosulfate

pH-dependent surface charging and points of zero charge. IV. Update and new approach.

The iron vanadate, FeVO4, was prepared and characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) It was found that FeVO4 could effectively catalyze H2O2 to generate active hydroxyl radical OH, which was confirmed with electron spin resonance (ESR) spin-trapping technique Therefore, it was employed as a heterogeneous Fenton-like catalyst in the present contribution, and its catalytic activity was mainly evaluated in terms of the degradation efficiency of Orange II Compared with the conventional heterogeneous Fenton-like catalysts, α-Fe2O3, Fe3O4 and γ-FeOOH, FeVO4 possessed a much higher catalytic activity The high catalytic activity possibly involved in a special two-way Fenton-like mechanism, that is, the activation of H2O2 by both Fe(III) and V(V) in FeVO4 Moreover, FeVO4 possessed a wide applicable pH range and its catalytic activity was slightly affected by the solution pH values in the range of 3–8

FeVO4 as a highly active heterogeneous Fenton-like catalyst towards the degradation of Orange II

Iron tetrapolyvanadate (Fe2V4O13) was prepared and characterized by X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) measurement and scanning electron microscopy (SEM). It was found that Fe2V4O13 could effectively catalyse H2O2 to generate active OH; therefore, Fe2V4O13 was employed as a new two‐metal heterogeneous Fenton‐like catalyst. The decomposition of H2O2 and the degradation of Acid Orange II catalysed by Fe2V4O13 could be well described with a simple pseudo‐first‐order rate equation between the reaction temperatures of 15 °C and 30 °C. It was inferred from the reaction activation energy data that the generation of the hydroxyl radical was a control step in a series of reactions for the oxidation of Acid Orange II in the presence of H2O2 and Fe2V4O13. The catalytic activity of Fe2V4O13 towards degradation of Acid Orange II was not only much higher than that of α‐Fe2O3, V2O5 and FeVO4 but also than that of their mixtures with an identical ratio of Fe and V, such as 2FeVO4 + V2O5 and Fe2O3 + 2V2...

Application of Fe2V4O13 as a new multi-metal heterogeneous Fenton-like catalyst for the degradation of organic pollutants.

A new photo-Fenton-like catalyst with high activity, Fe2V4O13, has been found It can be obtained by a simple wet chemical process The catalyst has a nano-lamellar structure with a thinness of less than 100 nm, a BET surface of 5226 m2 g−1, and a band-gap of 159 eV favorable to absorption of visible light Experiments demonstrated that Fe2V4O13 could effectively catalyze degradation of Acid Orange II (AOII) by H2O2 in visible light The degradation was well fitted by a simple pseudo-first-order reaction with a rate constant of 00965 min−1 Moreover, the photo-Fenton-like catalytic activity of Fe2V4O13 was much higher than that of not only α-Fe2O3 and V2O5 but also their mixture (Fe2O3 + 2V2O5) with an identical atomic ratio of Fe and V, and that of both Fe3O4 and γ-FeOOH The high catalytic activity of Fe2V4O13 possibly involves a special two-way Fenton-like, semiconductor photo-catalytic mechanism and the synergistic activation of Fe(III) and V(V) in Fe2V4O13 towards H2O2

Photo-Fenton-like catalytic activity of nano-lamellar Fe2V4O13 in the degradation of organic pollutants

The invention discloses the application of solid acid that is FexVyOz used as a Fenton-like reaction catalyst. The FexVyOz is FeVO4, Fe2V4O13 or Fe4V6O21. The catalyst can coordinate with water to form tetrabasic acid in water solution due to the strong polarization force of ferrum and vanadium, and the ferrum and the vanadium can also catalyze H2O2 to generate highly active hydroxyl radicals to effectively degrade organic pollutants. The application introduces ferric vanadate class solid acid to the Fenton-like reaction, good H2O2 activation effect is achieved, the self decomposition problem of the H2O2 is improved, and a bran-new effective way for performing the advanced treatment on biologic hard-degradation organic wastewater is provided.

Application of solid acid FexVyOz as Fenton-like reaction catalyst

Molecular co-crystallization to enhance photocatalytic activity is a new strategy. Here, we design and grow two molecular cocrystals based on octafluoronaphthalene (OFN) by utilizing a liquid-assisted grinding method. Octafluoronaphthalene–9,10-dimethylanthracene (OFN-DMA)...

Jingheng Deng

Papers

FeVO4 as a highly active heterogeneous Fenton-like catalyst towards the degradation of Orange II

Application of Fe2V4O13 as a new multi-metal heterogeneous Fenton-like catalyst for the degradation of organic pollutants.

Photo-Fenton-like catalytic activity of nano-lamellar Fe2V4O13 in the degradation of organic pollutants

Application of solid acid FexVyOz as Fenton-like reaction catalyst

Arene-Perfluoroarene Interactions in Molecular Cocrystal for Enhanced Photocatalytic Activity