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The improvement of the sono-photo-Fenton process at nearby neutral pH (~ 6.2) and high iron concentration (5 mg L−1) by the addition of the juice of Passiflora edulisf. flavicarpaDegener (yellow passion fruit) on the degradation of imipenem in water is reported for the first time. Considering that the combination of sonochemistry with photo-Fenton takes advantage of the in situ sonogeneration of H2O2, the effects of frequency and acoustic power for the H2O2 accumulation were established initially. The sonication at 578 kHz and 23.8 W favored the H2O2 generation. Using such frequency and power, the antibiotic was synergistically degraded by the sono-photo-Fenton system in distilled water, leading to ~ 90% removal at 120 min of treatment. An atomic charge analysis showed that thioether, β-lactam ring, and carboxylic acid moieties on the imipenem structure were very prone to interactions with the HO• generated in the sono-photo-Fenton process. Indeed, the primary transformation products (TPs) came from the oxidation of the thioether, the opening of the β-lactam ring, and decarboxylations. Such TPs had a lower probability than imipenem to be active against bacteria. Besides, the addition of small amounts (2.5–10 µL) of the yellow passion fruit juice to the sono-photo-Fenton system significantly improved the pharmaceutical elimination. However, a juice excess (e.g., 100 µL) caused a detrimental effect due to competing effects by radicals. The juice of the yellow passion fruit induced analogous effects to citric acid (a commercial complexing agent) on the sono-photo-Fenton process. Indeed, the degradation of imipenem in simulated hospital wastewater by sono-photo-Fenton was improved by the yellow passion fruit juice (~ 38% at 60 min), and it was similar to that with citric acid (~ 39% of removal at 60 min). Thus, the commercial reagent can be replaced by a natural and low-cost complexing agent (e.g., yellow passion fruit juice or fruit wastes containing citric acid), as an enhancer of the sono-photo-Fenton process carried out at near-neutral pH and high iron concentration for degrading imipenem in water. [ABSTRACT FROM AUTHOR]

This study investigates caffeine degradation and mineralisation using Fenton and photo-Fenton processes through a 2k Factorial Design. Key parameters varied include Fe2+ concentration (2 and 10 mg/L), H₂O₂ concentration (50 and 500 mg/L), light intensity (0 and 96 W), and reaction time (0 and 60 min) to optimise degradation. The experimental setup featured a 1 L glass contact column in a UV-controlled chamber with an initial caffeine concentration of 20 mg/L. Results revealed that Fenton was inefficient, achieving only 12% degradation and 9% mineralisation, with dimethylparabanic acid as the main by-product. Conversely, photo-Fenton attained 88% degradation and 40% mineralisation, demonstrating the significant influence of UV light. Energy consumption varied from 3.33 to 50 kWh.m−3. Optimal conditions identified were 10 mg/L Fe2+, 50 mg/L H₂O₂, 96 W UV intensity, and a 60-minute reaction time, highlighting the effectiveness of advanced photo-Fenton oxidation for caffeine treatment. [ABSTRACT FROM AUTHOR]

This work investigated the photochemical degradation of malachite green (MG), a cationic triphenylmethane dye used as a coloring agent, fungicide, and antiseptic. UV photolysis was ineffective in the removal of MG as only 12.35% degradation of MG (10 mg/L) was achieved after 60 min of irradiation. In contrast, 100.00% degradation of MG (10 mg/L) was observed after 60 min of irradiation in the presence of 10 mM H2O2 by UV/H2O2 at pH 6.0. Similarly, complete removal (100.00%) of MG was observed at 30 min of the reaction time by UV/H2O2/Fe2+ employing [MG]0 = 10 mg/L, [H2O2]0 = 10 mM, [Fe2+]0 = 2.5 mg/L, and [pH]0 = 3.0. For the UV/H2O2 process, the degradation efficiency was higher at pH 6.0 than at pH 3.0 as the k obs values were 0.0873 and 0.0690 min−1, respectively. However, UV/H2O2/Fe2+ showed higher reactivity at pH 3.0 than at pH 6.0. Chloride and nitrate ions slightly inhibited the removal efficiency of MG by both UV/H2O2 and UV/H2O2/Fe2+ processes. Moreover, three degradation products (DPs) of MG, (i) 4-dimethylamino-benzophenone (DABP), (ii) 4-amino-benzophenone (ABP), and (iii) 4-dimethylamino-phenol (DAP), were identified by GC-MS during the UV/H2O2 treatment. These DPs were found to demonstrate higher aquatic toxicity than the parent MG, suggesting that researchers should focus on the removal of target pollutants as well as their DPs. Nevertheless, the results of this study indicate that both UV/H2O2 and UV/H2O2/Fe2+ processes could be implemented to alleviate the harmful environmental impacts of dye and textile industries. [ABSTRACT FROM AUTHOR]

In this work, a novel highly efficient perovskite type NdFeO3/porous In2O3 heterojunction photocatalyst is designed through a simple solvothermal process. The as-synthesized photocatalysts were characterized by XRD, Raman, FT-IR, UV–vis DRS, FE-SEM, HR-TEM, and XPS characterization techniques. The superior photo-Fenton (PhF) degradation efficiency of the NdFeO3/In2O3 heterojunction photocatalyst is notably higher for coloured pollutants, upon visible light irradiation. The photocatalytic degradation of rhodamine-B (rhB) over the NdFeO3/In2O3 heterojunction was higher (92.5%) than pure NdFeO3 and In2O3. Furthermore, the NdFeO3/In2O3 heterojunction photocatalyst also exhibits remarkable degradation performance in the visible light assisted PhF process of various pollutants (methylene blue, methyl orange, phenol, and tetracycline). The increase in photocatalytic performances of the NdFeO3/In2O3 heterojunction is credited to the improvement in efficiency of separating electron–hole pairs and superior PhF mechanism from the perovskite type NdFeO3. The improved visible light degradation efficiency and PhF process of the prepared material could be utilized in real-world effluents and waste water treatment processes. [ABSTRACT FROM AUTHOR]

Developing cost‐effective and efficient photo‐Fenton catalysts is crucial for advancing photo‐Fenton technology. MoS2 is a representative transition metal disulfide with attractive photoresponsiveness, making it ideal for preparing composite photo‐Fenton catalysts. In this study, natural molybdenite was innovatively utilized as a source of MoS2 (OM) to synthesize a low‐cost and efficient Fe@MoS2 (OMF) composite photo‐Fenton catalyst by comminution and adsorption, which was then applied to the remediation of antibiotic‐contaminated water. The OMF composites exhibited significant catalytic activity, with a kinetic rate constant of 0.022 min−1, which was 3.1 times higher than that of the original OM (0.007 min−1), indicating a 3% increase. This was attributed to the synergistic effect of many photogenerated electrons and reversible Mo4+/Mo6+ redox pairs, which accelerated the regeneration of Fe2+. After three cyclic tests, the concentrations of dissolved Fe2+ and Mo2+ ions remained below 0.38 mg/L and 0.17 mg/L, respectively. This indicates the high reusability of the catalyst in cyclic experiments. Ultimately, the main active species, •OH and •O2−, were generated during the photo‐Fenton process, contributing significantly to TC degradation. This study may serve as a reference for the development and application of natural mineral composite photo‐Fenton catalysts in the treatment of organic wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] Low photo-induced carrier recombination rate, exceptional light absorption, and advantageous recycling performance are crucial attributes of semiconductor photocatalyst for wastewater purification. Herein, based on in-situ reaction, close-contact S-scheme bismuth chromate/bismuth oxide/ferroferric oxide@porous carbon microspheres (Cr 2 Bi 3 O 11 -Bi 2 O 3 /Fe 3 O 4 @PCs) (F-CBFP) was fabricated using alginates as precursor. Due to the abundance of functional groups on the porous carbon (PCs), Bi 2 O 3 and Cr 2 Bi 3 O 11 nanoparticles (NPs) are in situ deposited onto the highly conductive 3D magnetic porous Fe 3 O 4 @PCs microsphere surface, which not only form tight interfacial contacts and reduces interfacial potential barriers but also prevent agglomeration or shedding of the NPs during photocatalytic reactions. Moreover, density functional theory (DFT) calculations further confirm that the formation of a robust built-in electric field (BIEF) within F-CBFP prompts photo-induced electrons in the conduction band (CB) of Bi 2 O 3 to combine with holes in the valence band (VB) of Cr 2 Bi 3 O 11 , effectively constructing a S-scheme heterojunction system. Also, Fe 3 O 4 can act as a Fenton catalyst, activating the H 2 O 2 generated by Cr 2 Bi 3 O 11 under illumination. In wastewater treatment, the obtained F-CBFP shows remarkable photo-Fenton degradation (towards methyl orange (97.8 %, 60 min) and tetracycline hydrochloride (95.3 %, 100 min)) and disinfection performance (100 % E. coli inactivation), and exceptional cyclic stability. [ABSTRACT FROM AUTHOR]

Global industrialization has led to a pressing concern of water pollution from refractory reactive dyes. Among Advanced oxidation processes, the Fenton photocatalyst, particularly cobalt ferrite (CoFe2O4), is gaining attention due to its advantages, including stability, visible light utilization, recyclability, cost-effectiveness, and light corrosion resistance. This study investigates the synthesis and application of cobalt ferrite magnetic nanoparticles (CFNs) as a Fenton-like catalyst for degrading Reactive Blue 19 (RB19) dye under UV irradiation. CFNs were characterized using XRD, SEM, and VSM techniques. The photo degradation of RB19 was assessed under various conditions, including catalyst dosage, oxidant amount, RB19 concentration, and pH. The maximum removal efficiency of RB19 was achieved as 97.3% for synthetic wastewater under the optimal conditions of pH 3, CoFe2O4 dosage (1.5 g/L), reaction time = 60 min, and H2O2 (80 mM) in the presence of UV radiation (18 W) at the ambient room temperature of 22 °C. The results revealed that the CFNs exhibited high stability, reusability, and catalytic activity. Moreover, the mineralization studies indicated significant removal rates for both RB19 and chemical oxygen demand (COD). The findings suggest the promising application of CFNs in advanced wastewater treatment processes. [ABSTRACT FROM AUTHOR]

Photocatalysis is an efficient technology for the degradation of pollutants. However, it still needs to be improved. In this study, magnetic Z‐scheme FeP/CdS composites heterojunction photocatalysts were prepared by a facile hydrothermal method, and the structure, morphology, optical, and photocatalytic properties of the prepared composites were investigated in detail. The efficiency of tetracycline hydrochloride (TCH) removal by FeP/CdS composites was investigated under different reaction conditions (including different FeP and CdS ratios, catalyst dosage, hydrogen peroxide consumption, temperature, and initial pH). FeP/CdS composites exhibited better catalytic performance compared with pure components. The F1Cd1 composite (mass ratio of FeP to CdS is 1:1) achieved 92.7% removal efficiency of TCH; moreover, the F1Cd1 composite still exhibits a high stability after five consecutive cycles. The capture experiments on the active material showed that the removal of TCH by the F1Cd1 composite was mainly dominated by •OH; however, •O2−, e−, and h+ played a minor role, and the degradation mechanism was revealed by combining various characterization techniques. The introduction of cadmium sulfide formed an effective photogenerated carrier transport channel at the interface with the iron phosphide surface, which could accelerate the transfer and separation of photo‐excited e−/h+ pairs, thus improving the degradation performance of TCH. [ABSTRACT FROM AUTHOR]

The conventional heterogeneous photo-Fenton systems suffer from limited surface active sites, sluggish Fe3+/Fe2+ cycle, and low activation efficiency of hydrogen peroxide, thus limiting their applications. Herein a 0D/3D FeOOH/BaTiO3 composite photo-Fenton catalyst system was proposed. The typical microstructure in which FeOOH nanoparticles uniformly anchored on the flower-like BaTiO3 microsphere endows the composite catalysts with abundant active sites and intimate heterojunctions, which are conducive to charge carrier separation and transportation, as confirmed by the electrochemical and XPS characterization results. Benefiting from these advantages, the degradation rate of RhB with 1:4 FeOOH/BaTiO3 was significantly increased to 0.23 min–1, which was 40.5 and 7.9 times higher than that of BaTiO3 and FeOOH when a trace amount of H2O2 (6 mM) was present. In addition, the catalysts also showed superior degradation efficiency in decomposing the antibiotic TC and possessed high recycle stability. The triggered Fenton reactions give rise to abundant •OH, which was confirmed to be the dominated active species. According to the band structure analysis and control experiment results, it was believed the smooth photoelectron transfer from BaTiO3 to FeOOH accelerated the Fe3+/Fe2+ cycle, facilitated activation of H2O2, and boosted photo-Fenton reactions. This work provides a perspective on the design of high-performance photo-Fenton catalysts to tackle wastewater treatment. [ABSTRACT FROM AUTHOR]

Sulfamethoxazole (SMX) is an antibiotic that is extensively used in veterinary medicine, and its occurrence in wastewater and surface water can reach up to 20 μg/L. SMX is categorized as a pollutant of emerging concern by the US EPA due to its persistence and effects on humans and the environment. In this study, photo-Fenton technology is proposed for the removal of SMX. Aqueous solutions of SMX (50.0 mg/L) are treated in a 150 W UV photoreactor, using [Fe2+]0 = 0.5 mg/L and varying [H2O2]0 = 0–3.0 mM. During the reaction, colour (AU) was assessed along with SMX (mg/L), turbidity (NTU), and TC (mg/L). SMX degrades to aromatic intermediates with chromophoric groups, exhibiting colour (yellow to brown) and turbidity. As these intermediates are mineralized into CO2 and H2O, the colour and turbidity of the water lose intensity. Using a molar ratio of 1 mol SMX:10 mol H2O2, the maximum degradation of aromatic species takes place (71% elimination), and colourless water with turbidity < 1 NTU is obtained. A kinetic modelling for aromaticity loss and colour formation as a function of the oxidant concentration has been proposed. The application of this model allows the estimation of oxidant amounts for an efficient removal of SMX under environmentally friendly conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeOOH/F-Ce composites exhibit excellent catalytic activity under visible light. • The two-dimensional porous structure facilitates the diffusion and transport of reactant molecules, enhancing the degradation efficiency. • The S-scheme heterojunction promotes visible light absorption and charge transfer, accelerating the Fe3+/Fe2+ cycle. The utilization of two-dimensional (2D) materials to construct heterogeneous catalysts provides opportunities for environmental remediation, while the incorporation of porous structures can further enhance catalytic performance. In this work, a porous 2D FeOOH/fluorine-cerium (F-Ce) nanosheet composite was designed and synthesized by a simple impregnation-precipitation method. The unique 2D porous structure of F-Ce promoted the high dispersion of FeOOH quantum dots (QDs) (∼1.4 nm) and their tight integration to form S-scheme heterojunctions. This structure offered a greater number of active sites, and significantly improved the capacity of light absorption and the separation and migration efficiency of photogenerated carriers, thus improving catalytic activity. This catalyst achieved a phenol removal rate of 98.1 % within 20 min during the photo-Fenton reaction, which significantly surpasses pure FeOOH (32.9 %) and F-Ce (21.7 %) alone. In particular, the optimized 14FeOOH/F-Ce catalyst achieved more than 95.0 % degradation efficiency within a remarkably short period of 5 min. Mott Schottky and in situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) studies demonstrated that the S-scheme charge transfer mechanism of this heterojunction synergistically enhanced the catalytic activity of the Fenton-like reaction. This study provides valuable insights for designing efficient 2D porous heterojunction catalysts for visible-light-driven Fenton applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • CA-Cu/TCN was fabricated by a citric acid (CA)-initiated self-assembly strategy. • CA induced the formation of tubular morphology, bridging C replacement, and N defects. • Ultra-dispersed CuN x sites and N vacancies resulted in excellent activity of CA-Cu/TCN. • Efficient degradation of ciprofloxacin (95.9 %) in CA-Cu/TCN photo-Fenton system. • Ciprofloxacin degradation was a gradual detoxification process for harmless disposal. The low utilization of visible light and easy recombination of charge carriers of graphitic carbon nitride (CN) restrain its application as photo-electron donor and metal site support in photo-Fenton system. Herein, a hydrogen bond-induced supramolecular self-assembly strategy was created to fabricate an ultra-dispersed Cu-loaded porous tubular CN composite (CA-Cu/TCN) by the hydrothermal–pyrolysis method with citric acid (CA) as initiator and chelating agent. CA-Cu/TCN with rich nitrogen vacancies (NVs) and abundant ultra-dispersed CuN x sites exhibited narrow bandgap, favorable visible light absorption capability, and high separation and transfer efficiency of charge carriers. CA-Cu/TCN effectively catalyzed the activation of H 2 O 2 for generating abundant reactive oxygen species under visible light irradiation, contributing to efficient degradation of ciprofloxacin (CIP) with removal rate of 95.9 % and kinetic rate constant of 0.0948 min−1. The superior catalytic activity of CA-Cu/TCN can be ascribed to the effective transport of photogenerated electrons, high specific surface area, atomically dispersed Cu species, and enriched surface NVs. The mechanism of photo-Fenton catalytic degradation of CIP and possible degradation pathways were proposed as the dominant role of 1O 2. Toxicity evaluation of CIP and intermediates indicated that the degradation of CIP was a gradual detoxification process. This work offers a novel self-assembly strategy to design and synthesize highly active and sustainable visible light-driven photo-Fenton catalysts for effectively degrading organic pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • The spin state of Co3+ has a significant effect on photo-Fenton process. • Intermediate-spin state Ce-LaCoO 3 has narrower band gap. • Co3+ in the intermediate-spin state facilitates the catalytic decomposition of H 2 O 2. • The tetracycline removal rate of intermediate-spin state Co3+ was 91.6 % in 2 h. • Intermediate-spin state Co3+ maintained stably photo-Fenton activity after 5 cycles. The water pollution caused by the abuse of antibiotics has significant harmful effects on the environment and human health. The photo-Fenton process is currently the most effective method for removing antibiotics from water, but it encounters challenges such as inadequate response to visible light, low yield and utilization of photogenerated electrons, and slow electron transport. In this study, spin state regulation was introduced into the photo-Fenton process, and the spin state of Co3+ was regulated through Ce displacement doping. The intermediate-spin state Ce-LaCoO 3 could degrade 91.6 % of tetracycline within 120 min in the photo-Fenton system, which is 15.2 % higher than that of low-spin state LaCoO 3. The improved degradation effect is attributed to the reasons that Ce-LaCoO 3 in the intermediate-spin state have lower band gap, better charge transfer ability, and stronger adsorption capacity of H 2 O 2 , which can accelerate the redox cycle of Co2+/Co3+ and promote the generation of ·OH. This study presents a unique strategy for synthesizing efficient photo-Fenton materials to treat antibiotic wastewater effectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graphite carbon modified CuFe 2 O 4 (C/CFO) composites were synthesized. • C/CFO, H 2 O 2 and light formed a novel photo-Fenton degradation system. • The synergistic system exhibited high degradation efficiency of tetracycline. • Fe and Cu as electron-poor reaction centers to promote valence cycling of metals. • Oxygen vacancies as electron-rich reaction centers to decompose H 2 O 2. Controlling high recombination of photogenerated carriers and optimizing low cycling of metal valence states are the two key control steps in enhancing photo-Fenton oxidation. To achieve multiscale synergy of photo-Fenton degradation, graphite carbon-modified copper ferrite composites (C/CFO) with poor/rich dual electron reaction centers were synthesized through direct carbonization of Fe/Cu bimetallic organic frameworks. A novel photo-Fenton catalytic system was constructed by irradiating the Fenton reaction with visible light. The photo-Fenton degradation efficiency of C/CFO for tetracycline (100 mg‧L−1) was 93.69% ± 0.02%, and the degradation rate constant was 4.84 times higher than that of the control. Optimized preparation and catalytic conditions, ensured good cyclic stability and broad applicability of C/CFO. This excellent stability performance improvement can be attributed to the following main factors: (1) The introduction of graphite carbon not only increases the specific surface area of C/CFO, but also acts as a bridge between the dual electron reaction centers, facilitating the transfer of photogenerated electrons. (2) On the one hand, the electron-poor reaction centers Fe and Cu capture photogenerated electrons, accelerate the Fenton reaction, and realize the valence cycling of Fe and Cu. On the other hand, the electron-rich reaction centers (oxygen vacancies) act as active sites for H 2 O 2 adsorption, which greatly accelerate the decomposition of H 2 O 2. Overall, the synergy of dual electron reaction centers effectively promoted photo-Fenton oxidation. [ABSTRACT FROM AUTHOR]

NH 2 -MIL-88B(Fe)/CuInS 2 S-scheme heterojunction as iron-copper bimetallic photo-Fenton system is fabricated via a straightforward hydrothermal process. It shows excellent photothermal-photocatalytic Fenton property for degradation of tetracycline in low-temperature wastewaters, due to the synergistic effect of bimetallic codoped Fenton system and formation of S-scheme heterojunction. [Display omitted] Enhancing the velocity of the oxidation–reduction cycle is crucial for improving the catalytic efficiency of Fenton processes. Therefore, the development of an effective strategy for wastewater degradation at low temperatures is essential. In this context, we present the preparation of an NH 2 -MIL-88B (Fe)/CuInS 2 S-scheme heterojunction. Specifically, CuInS 2 nanoparticles are introduced onto the Ferro-organic skeleton, resulting in the exposure of a significant number of active surface sites. Furthermore, NH 2 -MIL-88B (Fe)/CuInS 2 demonstrates an extended photoresponse into the long-wavelength region, which contributes to its excellent photothermal properties. Notably, the degradation rate of tetracycline in low-temperature aqueous environments reaches as high as 99.7 %, several times higher than that of the original sample. Additionally, the hydrogen production of NH 2 -MIL-88B (Fe)/CuInS 2 is 2.23 times that of single NH 2 -MIL-88B (Fe) and 3.46 times that of single CuInS 2. Moreover, the system exhibits good H 2 O 2 evolution performance, forming an efficient photo-Fenton system. The charge transfer process in S-scheme heterojunction is confirmed using in-situ X-ray photoelectron spectroscopy and electron paramagnetic resonance. Both transient photoluminescence and photo electrochemical tests further validate the enhanced photoelectrochemical properties of the NH 2 -MIL-88B (Fe)/CuInS 2 S-scheme heterojunction. The exceptional performance of this system can be attributed to the synergistic effects of the S-scheme heterojunction and the bimetallic codoped photo-Fenton system. This research presents a novel approach for the breakdown of low-temperature wastewater using an improved photocatalytic Fenton system. [ABSTRACT FROM AUTHOR]

The investigation of photochemical degradation of chemical components in pharmaceutical wastewater by use of ultraviolet (UV) irradiation, UV in combination with sodium hypochlorite (UV/NaOCl), and Fenton’s reagent (UV/H2O2/Fe2+) was performed. Objective of this study was to determine the best alternative to the conventional wastewater treatment or pre- / post-treatment in combination with biological treatment to one of the four effluent source outlets. The effect of the advanced oxidation treatments provided varying degree of COD reduction for all four effluents. The results showed UV/H2O2/ Fe2+ treatments provided maximum chemical oxygen demand (COD) reduction of the anaerobic system outlet effluent. The combination of UV/H2O2/ Fe2+ (750 mg/L FeSO4+7500 mg/L H2O2) provided reduction in COD up to 75% upon three-hour UV exposure. The initial effluent COD was about 22000 mgO2/L and the treated effluent BOD5 /COD ratio was 0.50 showing greater amenability to biological processes. Sodium hypochlorite dosages between 3000 and 10000 mg/L achieved the results with little variation as compared to UV/H2O2/ Fe2+. Additionally, comparison was made of the UV exposure time required to reach the maximum reduction of COD value and the necessary effective oxidant dose to achieve the desired COD reduction, which could provide predictive model for the treatment of wastewater processes.

Phenol is a volatile organic compound, and conventional treatment processes prove to be ineffective for its degradation. The designable electron transfer structures of Fenton-based catalysts show great potential for wastewater treatment. However, attaining a balance between recycling and degradation efficiency remains a challenge. Herein, we prepared a photocatalyst with improved visible-light excitation characteristics. Magnetic N-TiO2/Fe3O4@MXene was prepared by loading N-TiO2 nanoparticles and Fe3O4 onto multilayered MXenes. N-TiO2/Fe3O4@MXene exhibited stable magnetic characteristics (27.1 emu/g) and a high degradation capacity for phenol. The catalyst also showed better performance for phenol removal under simulated solar-light (200–800 nm) irradiation compared with those of other catalysts. The phenol removal rate of the catalyst in the concentration range of 20–60 ppm reached 98% after 30 min of solar-light irradiation. The degradation curves of phenol were kinetically fitted. After four cycles of testing, the material maintained a high efficiency for the degradation of phenol. A total organic carbon removal rate of 61% was achieved in 10 min. The intermediates of phenol degradation were determined via liquid chromatography–mass spectrometry to gain insights into the degradation pathways of phenol. This study paves the way for the development of efficient photo-Fenton-based catalytic systems with good magnetic separation capabilities, which can promote their application in wastewater treatment. [ABSTRACT FROM AUTHOR]

Natural hematite supported cobalt (Co/Nat-Hem), a new heterogeneous catalyst, was successfully prepared by a simple impregnation technique. Textural, structural, functional groups and morphological aspects of the prepared catalyst were analyzed by BET, XRD, FT-IR, XRF, pHpzc, SEM-EDX methods. BET analysis shows that the Co/Nat-Hem catalyst has a specific surface area of ​​13.44 m2/g and a pore volume of 0.062 cm3/g. The SEM-EDX method showed that 7.19 wt% of the cobalt species were dispersed on the surface of the prepared catalyst. The catalytic activity of Co/Nat-Hem was evaluated by photo-Fenton oxidation of the dye Cong red (CR). The effect of reaction parameters on CR oxidation efficiency was investigated. Under optimal reaction conditions (1 g/L catalyst concentration, 0.2 mol/L H2O2 initial concentration and pH 3), the percentage of CR discoloration reaches 97% after 30 min. The Co/Nat-Hem catalyst achieved a synergistic ratio of 28.5%, which was added to the oxidation rate of the Nat-Hem catalyst. The stability of the Co/Nat-Hem catalyst was demonstrated by the limited activity of leachates in the homogeneous Fenton oxidation of CR. The phytotoxicity of the CR dye was tested during the irrigation of the bean (Vicia faba L.). [ABSTRACT FROM AUTHOR]

Hybrid poly‐ion complexes were synthesized through the complexation of a double hydrophilic copolymer with Ce(III) ions. These colloids act as reservoirs for cerium ions, enabling the synthesis of cerium‐based Prussian blue nanoparticles with a cubic structure, a narrow size distribution around 100 nm, and good colloidal stability in water. Upon high‐temperature calcination, these nanoparticles are transformed into a cerium/iron‐based metal oxide catalyst (CeO2/Fe2O3). The resultant composite catalyst demonstrates superior performance in the photo‐Fenton oxidation of methylene blue pollutants, achieving a conversion efficiency that rivals other metal‐based oxides and cerium‐based catalysts. [ABSTRACT FROM AUTHOR]

This study presents a surface engineering strategy utilizing electronic waste (e‐waste) to incorporate single‐atom catalysts on conjugated polymers. Employing a conjugated porphyrin polymeric photocatalyst, gold single‐atom‐site catalysts are successfully introduced using the acidic metal leachates from e‐waste, where metal speciation and composition are regulated during the metal loading processes. The resulting photocatalyst with gold single atoms demonstrates a remarkable hydrogen peroxide (H2O2) selectivity of up to 97.56%, yielding a pure H2O2 solution at 73.3 µm h−1 under white LED illumination. The produced H2O2 is activated to •OH radicals on the same polymer with mixed gold and iron atoms, enabling a photo‐Fenton reaction and the complete degradation of toxic microcystin‐LR within 10 min under visible light. This study highlights the universal applicability of the metal mining strategy in various photoreactions. It is believed that this discovery pioneers sustainable photocatalysis, allowing the tuning of reactivity and selectivity on photocatalytic surfaces using metal waste. [ABSTRACT FROM AUTHOR]

Low degradation rate for a long degradation time and poor cycle stability caused by rapid recombination of generated electron-hole pairs are tough challenges for photo-Fenton degradation The unique microstructure catalyst can provide enough catalytic surface to prevent the recombination of electron-hole pairs and facilitate the barrier-free transport of active species. In addition, the special hollow microsphere structure can effectively accelerate the Rhodamine B (RhB) penetration and the photo-Fenton process. Introducing SrWO 4 can increase oxygen vacancies and optimize the electronic structure of ZnFe 2 O 4 , thus enhancing electron transport and RhB degradation in the photo-Fenton process. This kind of catalytic material ZnFe 2 O 4 /SrWO 4 (ZFO/SW) in the photo-Fenton process can effectively degrade the 99.18 % RhB dye only within 20 min with remarkable cycling stability. This work demonstrates the high efficiency of ZFO/SW as a photocatalyst and confirms the contribution of the current design concept to the development of photo-Fenton degradation materials. [ABSTRACT FROM AUTHOR]

More than two billion people across the world do not have access to potable water. Communities globally are struggling with epidemic level disease outbreaks, limited water supply among other large-scale public health risks. Water is essential for life and several regions across the world have poor infrastructure for the management of potable water resources and lack critical wastewater treatment facilities. As the population of the Earth grows rampantly, the demand for water resources is increasing exponentially. Large-scale critical infrastructure chains are required to produce potable water from raw water sources, and developing countries continue to struggle economically and cannot afford the same treatment chains as the developed world. This research project evaluated the feasibility of two photocatalytic / photo-Fenton solar reactors on their capabilities to breakdown water contaminants present in natural hydro-systems and freshwater resources namely rivers in Chatham, Kent, England between September 2015 and August 2017. The photo-Fenton reaction and solar-photochemical reactors were designed, constructed, and tested for the removal efficiencies of Chemical Oxygen Demand (COD), ammonia, nitrates, nitrites, and phosphates via LCK curvetted tests, in addition to turbidity and colour. The water quality analysis and results showed that oversaturation of the photoFenton reagents reduces the effectiveness of the reaction, and that finding the correct chemical balance has a greater impact on the removal efficiencies of the five pollutants than the use of ultraviolet (UV) light catalyst. Under the conditions set by this research project, a smaller diameter of piping yields the best removal efficiencies of pollutants. The optimal photochemical balance of H2O2: Fe2+ has more of an impact on the effectiveness of treatment than the use of UV radiation. The ideal H2O2: Fe2+ ratio for the treatment of river water is close to 100:1 mg/L. The impact of semivariables such as diameter of pipe and UV influx on the effectiveness of treatment are not noticeable compared to the effect of changing the photo-Fenton chemical ratio. Moreover, the photo-Fenton process’ removal efficiency is directly proportional to the remaining H2O2 concentration, as the photochemical reaction proceeds. [ABSTRACT FROM AUTHOR]

With the abuse of antibiotics, its pollution poses an increasing threat to the environment and human health. Effective degradation of organic pollutants in water bodies is urgent. Compared to traditional treatment methods, advanced oxidation processes that have developed rapidly in recent years are more environmentally friendly, efficient and applicable to a wider range of organic compounds. FeWO4 was used in this study as the iron-based semiconductor material to modify and optimize the material design. Fe3O4/FeWO4 composites were prepared by a two-step hydrothermal method. The crystal structure, surface morphology, electrochemical properties and separability of the composite semiconductor were analyzed by XRD, XPS, UV-vis, SEM, EDS and Mott-Schottky. The results showed that, when the initial contaminant concentration was 30 mg/L, the initial solution pH was 4, the dosage of the catalyst was 25 mg and the dosage of hydrogen peroxide was 30 μL, the degradation efficiency of tetracycline hydrochloride (TCH) could reach 91% within 60 min, which was significantly improved compared to the performance of the single semiconductors Fe3O4 and FeWO4. In addition, the catalyst prepared in this experiment can be easily recovered by magnetic separation technology in practical application, which will not affect the turbidity of water while reducing the cost of catalyst separation and recovery. [ABSTRACT FROM AUTHOR]

The degradation of two textile dye molecules was studied using photochemical processes, both in the absence and presence of light. Various methods were employed, including photolysis/UV, combined H2O2/UV photolysis, Fe2+/UV treatment, Photo-Fenton/UV at 350 nm and Photo-Fenton with solar irradiation. The decolorization efficiency of dyes in aqueous solution was evaluated for two specific dyes: Bromothymol Blue (BTB) and Methyl Green (MG). These experiments were carried out in batch mode. The results demonstrated a synergy between light irradiation and the presence of Fenton's reagents, such as hydrogen peroxide and divalent iron. In addition, it was demonstrated that direct solar irradiation can be used without specific devices to achieve high efficiency at low cost. In the first part, we checked the impact of the various operating parameters. Reaction efficiencies were compared for the same system in the dark and under the assistance of an artificial or solar light source. In the second part, we studied the parameters of the Photo-Fenton process, such as the initial pH of the solution, the initial concentrations of oxidant, iron catalyst, and dye under irradiation from either light source. Whereas the mere photolysis without Fenton's reagents allowed decolorization yields below 26 %, addition of the oxidant (H2O2) or the catalyst (Fe(II) species amplified the treatment efficiency. However, the presence of both H2O2 and Fe(II) under light irradiation was shown synergetic with yields ranging from 72 to 85 % depending on the dye worked and the light source: because of its broader spectrum in the UV domain, solar irradiation led to the highest decolorization yields. The above results were obtained for well-defined proportions of dye and reagents: for a 20 mg/l dye solution, Fe(II) catalyst concentration equal to 10−3 M, peroxide concentration of 5.10−2 M and a pH of 3. These conditions allowed optimal production of OH· radicals, allowing high efficiency in systems using solar irradiation. [ABSTRACT FROM AUTHOR]

The highly crystalline mesoporous series of various percentages such as 1, 3 and 5% of CeO2-doped MoO3 nanocomposite were synthesized successfully by using ultrasonic wave-assisted sol–gel synthesis procedure and calcined at 873 K for 3 h. The synthesized CeO2-MoO3 nanocomposite material characterized by different techniques like XRD, Raman, FT-IR, FE-SEM, HR-TEM, BET, XPS and UV-DRS measurements to find crystallinity, surface morphology, surface area, structural and optical properties. Among these, 5% CeO2-MoO3 nanocomposite shows excellent photo-Fenton dye degradation activity of Rhodamine-B (Rh-B) dye in visible light irradiation using direct sunlight. Maximum degradation was observed (95.36% in 120 min) with optimum condition of pH, catalyst amount and H2O2 concentration. These nanocomposite material was recovered, recycle and its reusability also gives excellent results up to the 4th cycle. Similarly, turn over number, turn over frequency, kinetic study and scavenger study of photo-Fenton degradation reaction were also discussed. [ABSTRACT FROM AUTHOR]

Advanced oxidative processes, such as Photo-Fenton, transform organic contaminants due to the attack by radicals. In this context, the lethal and sub-lethal effects of the Cruiser® 350FS (CRZ) with the active ingredient thiamethoxam (TMX) were investigated using the planarian Girardia tigrina. Degradation of thiamethoxam by the Fenton process was also assessed by using theoretical studies and the efficiency of Solar-Fenton versus Fenton. The 48 h LC50 value of CRZ for planarians was 478.6 mg L−1. The regeneration of planarians was significantly affected for concentrations ≥ 17 mg·L−1 of TMX (24 h). The Solar-Fenton showed a high degradation percentage reaching ~70%. The theoretical model showed the atoms of the TMX molecule that will suffer attacks from the formed radicals. Current results open new perspectives concerning the treatment of TMX in the aquatic environment because the 70% degradation seems to be sufficient to reach concentrations that do not induce sub-lethal effects in planarians. Further studies should determine if the by-products generated might be toxic for planaria or other organisms. [ABSTRACT FROM AUTHOR]

Antibiotics may induce super-resistant bacteria if they are available in the environment. Therefore, the removal of aqueous nitrofurantoin (NFT), and more importantly, the removal of the remaining antimicrobial activity after treatment, by the photo-Fenton process, was herein studied. Degradation experiments were performed according to an experimental design (0.5% error; factors: concentrations of NFT, Fe3+, and H2O2). Degradation conditions were: 20 mg NFT L−1, 10 mg Fe3+ L−1, and 170 mg H2O2 L−1. Fixed parameters were: 100 mL of the NFT solution, pH 2.5, 15-min stirring, and 25.0 ± 0.5°C. The initial rate constant (k0) and the maximum oxidation capacity (MOC) of the system were 0.61 min−1 and 100%, respectively (R2 = 0.986). 97% of the NFT and 93% of the organic carbon initially present were removed. Five degradation products (DPs) were detected by HPLC-MS and their endpoints estimated by the ECOSAR (ECOlogical Structure–Activity Relationships) 2.0 software. NFT and its DPs presented no toxicity towards Lactuca sativa. The antimicrobial activity (Escherichia coli) of NFT and/or DPs was completely removed in 15 min. Structures were proposed for the detected DPs. In short, the tested advanced oxidation technology (AOP), besides being capable of removing and mineralizing aqueous NFT in a short time, 15 min, also rendered the treated water biologically inactive (no ecotoxicity, no antimicrobial activity). [ABSTRACT FROM AUTHOR]

Microalgae-based materials have gained significant attention considering their rich resources, cost-effectiveness, and environmental friendliness. Herein, iron-rich microalgae (Chlorella pyrenoidosa, CP) were treated by hydrothermal reaction under alkaline conditions to remove the protoplast and obtain a hollow shell with an FexOy core inside. Then, the iron-rich microalgae-based aerogel (Fe-CP aerogel) was fabricated through a freeze-drying process. The as-prepared Fe-CP aerogel exhibited superior adsorption performance, and the maximum adsorption quantity for Cu2+ could reach 208.3 mg/g due to the synergistic adsorption of the hollow shell of CP cells and FexOy core. The Fe-CP aerogel also possessed super-hydrophilicity and displayed high separation efficiency (over 99%) when used for separating different oil/water emulsions. Moreover, the existence of FexOy endowed the Fe-CP aerogel with photo-Fenton activity, thus exhibiting excellent antifouling performance. The prepared Fe-CP aerogel could be considered an ideal adsorbent, with green, efficient, low-cost, and regenerative properties, and has the potential for the practical treatment of wastewater. [ABSTRACT FROM AUTHOR]

Copyright of Tikrit Journal of Engineering Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Semiconductor based photocatalysis is considered as an effective and sustainable approach for the efficient treatment of effluents containing organic dyes and pharmaceuticals. Herein, visible light responsive g-C3N4/ NiFe2O4 (CN/NF) composite photocatalysts were designed by sol-gel auto-combustion assisted calcination method using ethylene glycol (EG) as a chelating agent. Bidentate nature and lower molecular weight of EG favour slow hydrolysis of Ni2+ and Fe3+ ions followed by formation of homogenous gel phase which under auto-combustion produced NF precursors. Calcination of the mixture of dicyandiamide (DCDA) and predetermined amount of NF precursors at 550 °C for 4 h resulted in the formation of CN/NF nanocomposites in which NF nanoparticles are anchored on thick plates of porous CN. The construction of CN/NF S-scheme heterojunctions was established through XPS studies and scavenging tests. The 10CN/NF nanocomposite exhibited superior photocatalytic Rhodamine B (RhB) degradation efficiency (98.6 %) which is 2.7 and 3.1 folds superior than that of pure NF and CN respectively. Additionally, the photocatalytic performance of 10CN/NF for tetracycline hydrochloride (TCH) degradation was found to be 84.32 %. The degradation efficiency was around 1.75 and 2.6 times higher than that was observed for pristine NF and CN correspondingly. The current study will bring fresh insights into the synthesis of CN/NF heterojunctions with an S-scheme charge transfer channel for the efficient treatment of waste waters containing dyes and antibiotics.

The increase in pork consumption and its reputation as one of the best sources of protein has led to growth in this industry, however, its production generates a significant amount of swine wastewater (SWW). Conventional biological treatment methods are typically used to treat SWW. However, their applicability in small and medium sized enterprises (SMEs) in the swine industry is limited due to their high space requirements. Therefore, advanced oxidation processes (AOPs) such as photofenton (PF) and electrocoagulation (EC) represent a potential alternative for SWW treatment due to their lower space requirements. The aim of this study was to treat SWW by integrating the PF process followed by EC as a technological couple to optimize the removal efficiency of pollutants present in SWW. Experiments were conducted in a 2 L batch reactor, examining the effects of hydrogen peroxide (H2O2) concentration (0.5, 2.5, 5.0 g L−1) and current density (10, 50, 90 A m−2) on pH, organic matter, nutrients, and germination index (GI). The results showed that the optimum process conditions correspond to 2.6 g L−1 H2O2 and a current density of 41 A m−2. Under these conditions, an effluent is obtained with pH values of 7.8, TSS of 385 mg L−1, COD of 254 mg L−1, BOD5 of 139.8 mg L−1, TN of 190.4 mg L−1 and GI of 117 %. The results showed that the effluent complies with the Colombian standards. From a cost perspective, the use of Photo-Fenton to treat wastewater under these conditions would be US$ 0.7 per liter.

This work investigated the photochemical degradation of malachite green (MG), a cationic triphenylmethane dye used as a coloring agent, fungicide, and antiseptic. UV photolysis was ineffective in the removal of MG as only 12.35% degradation of MG (10 mg/L) was achieved after 60 min of irradiation. In contrast, 100.00% degradation of MG (10 mg/L) was observed after 60 min of irradiation in the presence of 10 mM H2O2 by UV/H2O2 at pH 6.0. Similarly, complete removal (100.00%) of MG was observed at 30 min of the reaction time by UV/H2O2/Fe2+ employing [MG]0 = 10 mg/L, [H2O2]0 = 10 mM, [Fe2+]0 = 2.5 mg/L, and [pH]0 = 3.0. For the UV/H2O2 process, the degradation efficiency was higher at pH 6.0 than at pH 3.0 as the kobs values were 0.0873 and 0.0690 min−1, respectively. However, UV/H2O2/Fe2+ showed higher reactivity at pH 3.0 than at pH 6.0. Chloride and nitrate ions slightly inhibited the removal efficiency of MG by both UV/H2O2 and UV/H2O2/Fe2+ processes. Moreover, three degradation products (DPs) of MG, (i) 4-dimethylamino-benzophenone (DABP), (ii) 4-amino-benzophenone (ABP), and (iii) 4-dimethylamino-phenol (DAP), were identified by GC-MS during the UV/H2O2 treatment. These DPs were found to demonstrate higher aquatic toxicity than the parent MG, suggesting that researchers should focus on the removal of target pollutants as well as their DPs. Nevertheless, the results of this study indicate that both UV/H2O2 and UV/H2O2/Fe2+ processes could be implemented to alleviate the harmful environmental impacts of dye and textile industries.

Industrial wastewater, contaminated by dyes and antibiotics, poses significant environmental challenges. We developed Fe-doped Bi2WO6 (Fe:Bi2WO6) photocatalysts to enhance the photocatalytic activity and stability of Bi2WO6. The advanced oxidation processes (AOPs) of Fe, including the photo-Fenton process for rhodamine B (RhB) degradation and peroxymonosulfate (PMS) activation for Cefalexin (CFX) degradation, were investigated. The Fe doping altered the crystallization of Bi2WO6 and improved its photocatalytic performance, achieving 97.7% RhB degradation and 70.6% CFX degradation within 180 min. These results highlighted the potential of Fe:Bi2WO6 photocatalysts in wastewater treatment, emphasizing their stability and high activity across various conditions.

Sustainable water management is very important for industries with high water consumption and wastewater generation, such as the textile industry. This study aims to investigate the treatment of textile wastewater with ultraviolet (UV) assisted and Fe2+ catalyzed sodium percarbonate (SPC) oxidation, which is an eco-friendly treatment method in terms of both added oxidant and activation methods. Based on the removal efficiencies and reaction rates, a sorting was made as UV/SPC/Fe2+ > SPC/Fe2+ > UV/Fe2+ > UV/SPC > SPC > UV. It was observed that the removal efficiencies increased as the SPC dose increased, and decreased due to the scavenging effect with the 5 g/L oxidant dose, and the optimum SPC dose was determined as 2.5 g/L. It was determined that the removal efficiencies were higher in acidic conditions and high UV power applications. Under optimum operating conditions (pH:3, SPC dose: 2.5 g/L, Fe2+ dose: 1 g/L, UV lamps: 4), 68% COD, 80.9% UV254, and 92% color removal were achieved. Under optimum conditions energy cost, chemical cost, and operational cost were calculated as 11.9 $/m3, 0.20 $/m3, and 12.1 $/m3, respectively. By reducing the process COD concentration to 236.2 mg/L, discharge standards have been achieved, and the applicability of the UV/SPC/Fe2+ process was proven. [ABSTRACT FROM AUTHOR]

Herein, Mn, Fe, and Ni single atoms are designed to be embedded into the six‐membered cavity of the adjacent graphite phase carbon nitride layer, and the 2p orbitals of interlayer N atoms are hybridized with 3d orbitals of the Mn, Fe, and Ni single atom to form Mn–N–Fe–N–Ni charge transfer bridge throughout the six‐membered cavity of the graphite phase carbon nitride. The DFT calculations provide a clear explanation for how the p–d orbital hybridization of Mn–N–Fe–N–Ni atoms facilitate the creation of a charge‐transfer pathway. This pathway, which is located in the Mn–N–Fe–N–Ni charge‐transfer bridge, serve as the catalyst for the degradation of oxytetracycline hydrochloride through photocatalysis. The photoatalytic activity is much higher than the graphite phase carbon nitride. The effects of the Mn–N–Fe–N–Ni charge transfer bridge on the migration of photogenerated carriers, photocatalytic degradation performance, and degradation mechanism are discussed in detail. In order to improve the degradation efficiency of oxytetracycline hydrochloride, the Mn–N–Fe–N–Ni charge‐transfer bridge is utilized to activate peroxymonosulfate (PMS) under visible light exposure. The factors affecting the activation of PMS for oxytetracycline hydrochloride degradation are thoroughly investigated, and the degradation mechanism is also analyzed. This research contributes to a better comprehension of the photo‐assisted Fenton‐like effect of single‐atom photocatalysts. [ABSTRACT FROM AUTHOR]

In this study, Fe3O4/Ag magnetite-silver (MSx) nanocomposites were investigated as catalysts for advanced oxidation processes by coupling the plasmonic effect of silver nanoparticles and the ferromagnetism of iron oxide species. A surfactant-free co-precipitation synthesis method yielded pure Fe3O4 magnetite and four types of MSx nanocomposites. Their characterisation included structural, compositional, morphological and optical analyses, revealing Fe3O4 magnetite and Ag silver phases with particle sizes ranging from 15 to 40 nm, increasing with the silver content. The heterostructures with silver reduced magnetite particle aggregation, as confirmed by dynamic light scattering. The UV–Vis spectra showed that the Fe:Ag ratio strongly influenced the absorbance, with a strong absorption band around 400 nm due to the silver phase. The oxidation kinetics of organic pollutants, monitored by in situ luminescence measurements using rhodamine B as a model system, demonstrated the higher performance of the developed catalysts with increasing Ag content. The specific surface area measurements highlighted the importance of active sites in the synergistic catalytic activity of Fe3O4/Ag nanocomposites in the photo-Fenton reaction. Finally, the straightforward fabrication of diverse Fe3O4/Ag heterostructures combining magnetism and plasmonic effects opens up promising possibilities for heterogeneous catalysis and environmental remediation. [ABSTRACT FROM AUTHOR]

This paper reports a nanomixed valence FeWO 4 -coated 2D Ti 3 C 2 MXene (FW-MX) photocatalyst synthesised by a simple hydrothermal method. Ciprofloxacin, the main target pollutant, exhibited superior adsorption performance and high catalytic activity in the light-assisted Fenton system. In just 1 h, the removal rate of ciprofloxacin reached an impressive 76.89% using a minimal amount of FW-MX (10 mg). Meanwhile, the material exhibited good stability. Furthermore, the successful formation of mixed-valent FeWO 4 accelerated the rate-limiting step of Fe(III)/Fe(II) conversion, thereby enhancing the reactivity of the in situ photo-Fenton system. In the light-assisted Fenton system, FW-MX demonstrated greater potential compared to other common antibiotics, as FW-M100 exhibited superior photoreduction performance for heavy metal ions under the photo-Fenton oxidation system. This could further advance the practical application of AOPs technology in industrial wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Fabrication of efficient perovskite photo-Fenton catalytic systems is recognized as an effective strategy for clean water production. However, modifying perovskite catalysts effectively remains a formidable challenge. In this study, we prepared Bi-doped LaFeO 3 photo-Fenton catalysts using a facile microwave-assisted method. Various characterization techniques confirmed the successful formation of these Bi-doped LaFeO 3 perovskite materials. The photo-Fenton activity of the Bi-doped LaFeO 3 perovskite materials with varying Bi content was assessed by monitoring the degradation of methylene blue (MB) dye solution. Remarkably, the optimized Bi-doped LaFeO 3 (referred to as LBFO3) catalyst achieved approximately 93.64% degradation of MB within 100 min of visible light exposure, demonstrating exceptional efficacy in treating wastewater containing organic dye pollutants. The enhanced photocatalytic activity of the LBFO3 perovskite materials arises from the incorporation of Bi, leading to an expanded optical absorption range, increased specific surface area, and enhanced separation and migration of photo-generated carriers. Importantly, the LBFO3 photo-Fenton system exhibited remarkable stability during four successive cycling treatments, indicating promising practical applications. Additionally, quenching experiments were conducted to elucidate electron transfer in the LBFO3 catalyst related to the photo-Fenton degradation mechanism of MB. This study might pave the way toward designing novel perovskite based photo-Fenton systems for highly efficient degradation of waterborne contaminants. [ABSTRACT FROM AUTHOR]

Diclofenac sodium salt was photodegraded by means of advanced oxidation processes (AOPs), such as Fenton, photo‐Fenton and heterogeneous photocatalysis. For the latter different photocatalysts were compared, namely commercial titania P25 and titania metallized with gold (0.1 % Au/P25), silver (1 % Ag/P25) and palladium (0.1 % Pd/P25). Homogeneous treatments demonstrated effective in the degradation of the selected pollutant (>80 % conversion @2 h) when the irradiation occurred within the solution. Also, photo‐Fenton process assisted by visible light rather than UV was effective but slower and characterized by a toxicity of the residual solution due to unreacted H2O2. The photocatalyzed treatment performed at its best when P25 was used (70 % conversion @2 h), while modified photocatalysts reached the same conversion when H2O2 was added to the solution. Overall, in vitro toxicity tests using Daphnia Magna unveiled that the wastewater treated via M/TiO2 treatment and photo‐Fenton under UV in combination with H2O2 showed an acute toxicity comparable with the control group (almost 100 % viability @48 h). Conversely, the other processes failed to degrade completely either the pollutant or the hydrogen peroxide, leading to the mortality of 30–80 % of the individuals. An important outcome of the work is the direct comparison of different treatments to optimise the outcome, i. e. rapidity of degradation and non toxicity of the treated solution for living bodies. [ABSTRACT FROM AUTHOR]

In order to solve the problem of metal-organic framework MTL-100(Fe) powder which was difficult to be recycled and reused in industrial applications, this paper synthesized MTL-1 OO(Fe) powder by a hydrothermal method. The MTL-1 00(Fe)©porous ceramic composites were prepared by loading the powder on alumina porous ceramic using vacuum filtration method. The structure and properties of the MTL-1 00(Fe) and composites were characterized by using field emission scanning electron microscope-energy spectrometer (FE-SEM-ET)S), X-ray diffractometer (XRD), specific surface area analyzer (BET), and ultraviolet-visible spectrophotometer (UV-VTS). The photo-Fenton-degradation abilities in the H2O2 reaction system were investigated by simulating the dye wastewater with rhodamine B (RhB) solution. Results showed that the MTL-1 OO(Fe) presented an octahedral structure with a specific surface area as high as 1 152.75 m²/g. When the reaction temperature was 60 °C, the initial concentration of was 0.5 g/L and the initial concentration of RhB solution was 20 mg/L the degradation rate of RhB solution reached 99.26%. When the MTL-100(Fe)@porous ceramic composites were recycled for 5 times, the degradation rate of RhB solution still reached more than 98%. The composites present excellent recyclability and had promising for commercialization application. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeCu bimetallic MOFs (FeCuBDC) were prepared by a solvothermal method. • FeCuBDC, H 2 O 2 and light constructed a novel photo-Fenton degradation system. • The synergistic system showed efficient degradation activity of organic pollutants. • High-valence FeCu captures e− and promotes photogenerated charge separation. • Low-valence FeCu decomposes H 2 O 2 and drives the bimetallic valence cycling. The high ion leaching, low photogenerated charge separation efficiency, and slow metal valence cycling of Fe-based metal organic frameworks (MOFs) have limited their application in the deep treatment of organic pollutants. Herein, FeCu bimetallic MOFs (FeCuBDC) were synthesized using a modified solvothermal method, and a coupled photo-Fenton degradation system was successfully constructed. Degradation performance tests showed that FeCuBDC could efficiently degrade 99.3% ± 0.1% of 50 mg/L phenol within 40 min. The reaction rate constants of the photo-Fenton system were 11.0 and 64.7 times higher than those of the single Fenton reaction and photocatalysis, respectively. FeCuBDC also exhibits good cycling stability, degradation generalization, and excellent photoelectric catalytic properties. Such a considerable enhancement in the overall performance pertains to the following. First, the introduction of Cu into Fe-MOFs not only improves the crystallinity and stability, but also reduces the band gap value, increases the absorption capacity of visible light, and promotes the generation of photogenerated carriers. Second, the FeCu in MOFs are all mixed valence. Initially, the high-valence FeCu captures photogenerated electrons and promotes photogenerated charge separation and transfer. Then, the low-valence FeCu adsorbs and decomposes H 2 O 2 , accelerating the valence cycling of the bimetallic sites. The core of the reaction mechanism is that FeCuBDC effectively promotes the photo-Fenton synergy. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Fenton reaction refers to the reaction in which ferrous ions (Fe2+) produce hydroxyl radicals and other reactive oxidizing substances by decomposing hydrogen peroxide (H2O2). This paper reviews the mechanism, application system, and materials employed in the Fenton reaction including conventional homogeneous and non‐homogeneous Fenton reactions as well as photo‐, electrically‐, ultrasonically‐, and piezoelectrically‐triggered Fenton reactions, and summarizes the applications in the degradation of soil oil pollutions, landfill leachate, textile wastewater, and antibiotics from a practical point of view. The mineralization paths of typical pollutant are elucidated with relevant case studies. The paper concludes with a summary and outlook of the further development of Fenton‐like reactions. [ABSTRACT FROM AUTHOR]