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[Display omitted] • Coordinative Fe-N x improved the catalytic ability of FeOCN for photo-Fenton process. • The consumption of H 2 O 2 was reduced in the photo-Fenton process over FeOCN. • FeOCN showed high catalytic performance for tetracycline degradation. • The improved charge separation favored Fe(III)/Fe(II) conversion. • FeOCN exhibited wide applicable pH range and anti-interference ability to anions. Tetracycline (TC) antibiotics have been widely used over the past decades, and their massive discharge led to serious water pollution. Photo-Fenton process has gained ever-increasing attention for its excellent oxidizing ability and friendly solar energy utilization ability in TC polluted water treatment. This work introduced coordinative Fe into oxygen-enriched graphite carbon nitride (OCN) to form FeOCN composites for efficient photo-Fenton process. Hemin was chosen as the source to provide the source of coordinative Fe-N x groups. The degradation efficiency of TC reached 82.1 % within 40 min of irradiation, and remained 76.9 % after five runs of reaction. The degradation intermediates of TC were detected and the possible degradation pathways were gained. It was found that h+, OH, and O 2 − played major roles in TC degradation. Notably, the photo-Fenton performance of FeOCN was stable in highly saline water or strong acid/base environment (pH 3.0–9.0). Besides, H 2 O 2 can be generated in-situ in this photo-Fenton process, which is favorable for practical application. It can be anticipated that the coordinative FeOCN composites will promote the application of photo-Fenton oxidation process in TC polluted water treatment. [ABSTRACT FROM AUTHOR]

RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) is a highly toxic heterocyclic nitramine compound which enters the environment during manufacturing, disposal, or military training activities. This study aimed to evaluate the effectiveness of different treatment methods, including direct photolysis, photo-peroxidation, and the photo-Fenton oxidation, using low- and medium-pressure UV lamps for the degradation of RDX wastewater. Rate of degradation and mineralization of RDX, COD reduction, and nitrate content were compared for all these processes. In terms of RDX degradation, the study found that direct photolysis with 125-W medium-pressure UV lamp resulted in 71% removal rate. In contrast, the low-pressure UV lamp of 16 W intensity only showed removal rate of 35%. When comparing the UV/H2O2 process to direct photolysis, it was found that the degradation rate of RDX increased for both low- and medium-pressure systems. Among the different advanced oxidation processes evaluated, the photo-Fenton oxidation process resulted in the highest degradation of RDX compared to direct photolysis and photo-peroxidation processes. Specifically, the addition of 10 mL of Fenton's reagent at a ratio of 1:3 (H2O2:Fe2+) resulted in 98% and 57% removal of RDX within 60 min of irradiation time for the medium-pressure and low-pressure UV lamps, respectively. The highest levels of mineralization for RDX in terms of COD and nitrate removal, amounting to 90% and 42%, respectively were obtained using photo-Fenton oxidation in 60 min of treatment time. [ABSTRACT FROM AUTHOR]

Pyridine is an important raw material in the pharmaceutical industry. Aminopyridines are key intermediates for the synthesis of important pharmaceutical products. 2-Aminopyridine is used in the production of antibacterial and several antihistamines drugs. Pyridine compounds have harmful effects on the liver, kidneys, immune systems, and reproductive functions, and have potential carcinogenicity. It is very essential to degrade 2-aminopyridines from an aqueous environment on a priority basis. Large-scale application of Fenton/photo-Fenton processes employing ferrous salts Fe2+ may prove costlier for the complete treatment of contaminated water/wastewater containing such recalcitrant compounds. 100% degradation of 2-aminopyridine (10 mg·L–1) by the Fenton process required 180 min out of which 58% degradation was achieved in the first 60 min of the reaction. The photo-Fenton oxidation process showed an improved rate of degradation. Parameters like pH, the dosage of hydrogen peroxide, and iron extracted from laterite soil are optimized for the effective degradation and mineralization of 2-aminopyridine in water. Kinetic studies were also conducted using the optimum conditions for 2-aminopyridine degradation and, the pseudo-first-order kinetic equation has been fit up to the reaction time of 30 min. High-performance liquid chromatography analysis was also carried out to confirm the cleavage of the pharmaceutical compound 2-aminopyridine. [ABSTRACT FROM AUTHOR]

Pharmaceutical compounds 2-Aminopyridine were detected in drinking water, surface water, and groundwater. 2-Aminopyridine is a colourless solid used for manufacturing drugs, sulphapyridine which is extremely poisonous and carcinogenic. Its appearance in drinking water needs prior treatment to dispose of safely. Fenton, Photo-Fenton oxidation processes were carried out to degrade 2-Aminopyridine. Parameters like pH, the dosage of Hydrogen peroxide, and Iron are optimized for the effective degradation of a 2-Aminopyridine compound in water. The effect of the initial concentration (10-80) mg/L of a 2-Aminopyridine pharmaceutical compound on degradation was studied. Drug at initial concentration of 10 mg/L, 40 mg/L and 80 mg/L is 100% degraded in 30 mins,45 mins and 120 mins respectively. Similarly, COD removals of 94.6%, 88.6% and 81% were detected at 10 mg/L, 40 mg/L and 80 mg/L of initial drug dosage. The degradation was enhanced by photo-Fenton oxidation. Both the drug degradation and COD reduction were improved by UV-C-assisted photo-Fenton oxidation processes. [ABSTRACT FROM AUTHOR]

In this study, the effect of Fenton and photo-Fenton processes, which are advanced oxidation processes that use the hydroxyl radical for the decolorization of Novacron Black from aqueous solutions, on decolorization was investigated. Optimum levels of initial pH, temperature, hydrogen peroxide concentration, initial dyestuff concentration, and iron concentration were determined. Initial pH, Fe2+ concentration, temperature, and initial Novacron Black concentration are the most effective experimental parameters in the decolorization of Novacron Black with Fenton and photo-Fenton processes. While the Novacron Black concentration was 200 mg/L, the H2O2 concentration was 100 mg/L, the initial solution pH was 3, and the temperature was 20 °C, a decolorization efficiency of 82.1% was obtained in the Fenton process at a concentration of 5 mg/L Fe2+, while in the photo-Fenton process at a 2 mg/L Fe2+ concentration, a 94.6% decolorization efficiency was obtained. Upon decolorization of Novacron Black, the photo-Fenton process had a higher removal efficiency than the Fenton process, even at low iron concentrations. From data obtained at various concentrations of initial Novacron Black, the non-linear method was used to determine the decolorization kinetics of Novacron Black. Finally, an economic analysis was carried out to compare the differences in operating costs between Fenton and photo-Fenton processes. [ABSTRACT FROM AUTHOR]

Improving the efficiency of photocatalytic reaction is a long-term problem. Recently, the advantages of combining photocatalytic reaction with other reactions have become apparent. In this work, trinuclear iron cluster (Fe3) have been integrated on graphitic carbon nitride (g-C3N4) nanosheets, which were converted to α-Fe2O3/g-C3N4 by calcination. It can effectively utilize the synergistic effect of visible light and Fenton oxidation to carry out photo-Fenton synergistic catalytic degradation of pollutants, and the degradation rate of CFCN to tetracycline hydrochloride exceeded 80% within 45 min, which is 9 times higher than that of pure g-C3N4. In four cycles, the catalytic effect of the reaction remained stable. The enhanced catalytic performance can be attributed to the separation of electron–hole pairs due to the conversion of Fe3+ and Fe2+ in the Fenton reaction, allowing a large number of holes to be used directly for the degradation of tetracycline. It is worth mentioning that this catalyst can still function under high salinity conditions and it also has the ability to degrade some dyes (MB and RhB). This work will promote a new understanding of the degradation of organic contaminants by supported cluster catalysts, and prove the high efficiency of photo-Fenton synergistic catalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • PGDY@MIL(Fe/Cu) plasmonic Z-scheme catalyst was prepared via pore-confined growth. • Abundant C-Cu interfacial channels in PGDY@MIL(Fe/Cu) increased electrons transfer. • LSPR effect of PGDY enhanced light absorption and inspired numerous hot electrons. • PGDY@MIL(Fe/Cu) showed 4.1–235.6 times higher k D than the reported photo-Fenton catalysts. • PGDY@MIL(Fe/Cu) achieved over 98% TOC removal for DNT and excellent cycling stability. Constructing abundant interfaces in composite catalysts to promote their synergistic effects is the key, though a tough challenge for enhancing photo-Fenton catalysts performance. Herein, a pore-confinement strategy is proposed to construct plasmonic Z-scheme PGDY@MIL(Fe/Cu) for ultra-fast removal dinotefuran. Graphdiyne was grown on Cu sites of MIL(Fe/Cu) and formed nano-elliptical graphdiyne (PGDY) nanosheets within the confinement of pores, while the C-Cu interfacial channels were constructed to promote electron transfer in the catalytic process. Upon illumination, PGDY strongly coupled with the incident light and localized surface plasmon resonance (LSPR) could be excited, thus enhancing light absorption efficiency of PGDY@MIL(Fe/Cu) at 375–600 nm and inducing numerous hot electrons. These unique properties accelerated separation efficiency of PGDY@MIL(Fe/Cu) for photogenerated carriers, which boosted the generation rate of active radicals and Fe3+/Fe2+ and Cu2+/Cu+ cycling rates during photo-Fenton catalysis. Finally, PGDY@MIL(Fe/Cu) exhibited excellent catalytic degradation kinetics (99.1 % within 40 min), mineralization efficiency (98 % within 2 h), and catalytic cycling stability for dinotefuran (DNT) compared to the reported advanced catalyst. [ABSTRACT FROM AUTHOR]

Photo-Fenton oxidation is one of the most efficient advanced oxidation process that is used for the treatment of effluents containing recalcitrant compounds. In this research, the removal of an anionic surfactant, sodium dodecyl sulfate, by MnFe2O4/ZnO nanocatalyst using photo-Fenton advanced oxidation process has been investigated. In this study, the MnFe2O4/ZnO nanocomposite was firstly synthesized and characterized, and then applied in the photo-Fenton oxidation process under UV irradiation. The effect of different parameters, such as pH, catalyst dose and the amount of hydrogen peroxide, on the process were investigated. Under the optimum conditions, at pH = 7, with a surfactant concentration of 5 mg/L, at 30 min using 2.24 mL hydrogen peroxide, the surfactant removal efficiency was 100%. The results show that the proposed method using the synthesized nanocatalyst has a high efficiency in the removal of surfactants.

The traditional homogenous and heterogenous Fenton reactions have frequently been restrained by the lower production of Fe2+ ions, which significantly obstructs the generation of hydroxyl radicals from the decomposition of H 2 O 2. Thus, we introduce novel photo-Fenton-assisted plasmonic heterojunctions by immobilizing Fe 3 O 4 and Bi nanoparticles onto 3D Sb 2 O 3 via co-precipitation and solvothermal approaches. The ternary Sb 2 O 3 /Fe 3 O 4 /Bi composites offered boosted photo-Fenton behavior with a metronidazole (MNZ) oxidation efficiency of 92% within 60 min. Among all composites, the Sb 2 O 3 /Fe 3 O 4 /Bi-5% hybrid exhibited an optimum photo-Fenton MNZ reaction constant of 0.03682 min− 1, which is 5.03 and 2.39 times higher than pure Sb 2 O 3 and Sb 2 O 3 /Fe 3 O 4 , respectively. The upgraded oxidation activity was connected to the complementary outcomes between the photo-Fenton behavior of Sb 2 O 3 /Fe 3 O 4 and the plasmonic effect of Bi NPs. The regular assembly of Fe 3 O 4 and Bi NPs enhances the surface area and stability of Sb 2 O 3 /Fe 3 O 4 /Bi. Moreover, the limited absorption spectra of Sb 2 O 3 were extended into solar radiation by the Fe3+ defect of Fe 3 O 4 NPs and the surface plasmon resonance (SPR) effect of Bi NPs. The photo-Fenton mechanism suggests that the co-existence of Fe 3 O 4 /Bi NPs acts as electron acceptor/donor, respectively, which reduces recombination losses, prolongs the lifetime of photocarriers, and produces more reactive species, stimulating the overall photo-Fenton reactions. On the other hand, the photo-Fenton activity of MNZ antibiotics was optimized under different experimental conditions, including catalyst loading, solution pH, initial MNZ concentrations, anions, and real water environments. Besides, the trapping outcomes verified the vital participation of •OH, h+, and •O 2 − in the MNZ destruction over Sb 2 O 3 /Fe 3 O 4 /Bi-5%. In summary, this work excites novel perspectives in developing boosted photosystems through integrating the photocatalysis power with both Fenton reactions and the SPR effects of plasmonic materials. • Photo-Fenton-assisted plasmonic Sb 2 O 3 /Fe 3 O 4 /Bi photocatalyst has been introduced. • Sb 2 O 3 /Fe 3 O 4 /Bi recorded 92% of MNZ removal in 60 min under simulated solar light. • The collaboration between SPR effects and photo-Fenton reactions promoted photoactivity. • Sb 2 O 3 /Fe 3 O 4 /Bi enabled the formation of h+,.•OH, and •O 2 − via the boosted photo-Fenton reaction. • The Fe3+/Fe2+ cycles of Fe 3 O 4 upgraded both light utilization and photocarrier disintegration. [ABSTRACT FROM AUTHOR]

Manufacturing and handling of explosives for defence and civilian operations cause widespread environmental contamination. In this study, treatment of wastewater from a HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) production facility was evaluated by advanced oxidation processes, viz. photolysis (UV), photo-peroxidation (UV/H2O2) and photo-Fenton oxidation (UV/Fenton's reagent). The wastewater sample was highly acidic and was contaminated with HMX, RDX (hexahydro-1,3,5- trinitro-1,3,5-triazine) and nitrated with heavy loads of chemical oxygen demand (COD) and nitrate. During treatment, degradation rate of HMX and RDX and reduction in COD and nitrate levels were monitored. Maximum removal of RDX (99%) and HMX (98%) was achieved under both photo-peroxidation and photo-Fenton oxidation processes in an hour of UV irradiation. Reduction in COD (57.3%) and nitrate content (61.9%) was maximum with photo-Fenton's treatment system, using Fenton's reagent (H2O2/FeSO4) in 1:3 ratio. The photo-oxidation process followed pseudo-first-order reaction kinetics. Though the process was efficient in removing high explosives, it was moderate in removing COD and nitrate contents in wastewater. [ABSTRACT FROM AUTHOR]

The yeast production industry wastewaters contains high amount of chemical oxygen demand (COD), brownish color and recalcitrant organic components. In this work, one of the yeast production plant wastewaters operating in the Aegean Region, the color removal were studied with using Photo-Fenton (H2O2/Fe(II)/UV) oxidation processes. In this study, the Box–Wilson statistical experimental design method applied to optimization of decolorisation of the yeast production industry wastewater. For this reason, the initial oxidant and catalyst concentrations and pH of water were chosen as the experimental parameters on decolorisation. Color removal was observed during the experimental studies. Complete color removal (E=100%) was achieved with the addition of 2400 mg/L H2O2 and 121 mg/L Fe(II) at 3.7 pH after 120 min. of exposure to the UV irradiation.

Maya üretim endüstrisinin atığı, yüksek miktarda kimyasal oksijen ihtiyacı (KOİ), azot, koyu renk ve biyolojik olarak parçalanmayan organik bileşikler içermektedir. Bu çalışmada, Ege Bölgesi’nde faaliyet gösteren bir maya sanayinin atıksularının, renk giderimi Foto-Fenton (H2O2/Fe (II)/UV) oksidasyon yöntemi kullanılarak arıtılmaya çalışılmıştır. Box-Wilson istatistiksel deneysel tasarım yöntemi kullanılarak başlangıç oksidan ve katalizör konsantrasyonları ve suyun pH'sı gibi bazı çalışma parametrelerinin renk giderme üzerindeki etkileri araştırılmıştır. Çalışma süresince renk giderimi izlenmiş ve komple renk giderimi (E=%100) 120 dk. sonra, 3.7 pH'da 2400 mg/L H2O2 ve 121 mg/L Fe (II) ilavesinin olduğu UV oksidasyonu işlemi sonucunda elde edilmiştir.

Olive oil production in Turkey is quite common. A large volume of untreated olive oil mill wastewater (OMW) is being stored in evaporation rafts. Since there are high amounts of organic load, dark color, and phenolic compounds in OMW, an effective treatment process should be implemented. In this work, an advanced oxidation process (photo-Fenton) operating in a batch reactor was used to treat OMW. For this reason, the effects of some operating parameters such as the initial oxidant and catalyst concentrations and pH of water on total organic carbon (TOC) and color removals were investigated using the central composite experimental design method. The samples were analyzed at different times during the experiments to determine water quality parameters. Increasing oxidant concentrations did not imply a noticeable rise in the final removal percentages. On the contrary, the removal efficiencies for both color and TOC were decreased by increasing catalyst concentration. Optimum color and TOC removal efficiencies were achieved as 95% and 65% respectively, with the addition of 4,585 mg L-1 H2O2, 255 mg L-1 Fe(II), and at pH 4.7 after 90 min of oxidation under UV-C lights. [ABSTRACT FROM AUTHOR]

The main aim of the present research, as the first study, was coupling of hydrogen peroxide (H2O2), ferrous ions (Fe2+) and UV irradiation in a photo-Fenton system to degradation two antibiotics (e.g. meropenem and ceftriaxone) from aqueous solution. The tests were carried out at different experimental conditions namely solution pH, iron dosages, H2O2 concentrations, UV light intensities, temperatures, and initial antibiotic concentrations. The degradation rates of 99 and 96.2% were observed for respectively meropenem and ceftriaxone during 60 min treatment. Biodegradability tests illustrated that photo-Fenton system has a high performance in removing organic compounds and biodegradability enhanced remarkably after treatment. [ABSTRACT FROM AUTHOR]

Fe/Bi-nanocrystal phase transformation within BFPCs catalysts contributes to acceleration of electron transfer in Fenton chemistry in the presence of visible light (λ > 420 nm) irradiation. This enhanced system compared to the alike Fenton-like oxidation formed a myriad of HO• radicals outperforms in mineralization rate (>80% on average for varied EOPs), saving H 2 O 2 usage (85%) and reaction time (50%). [Display omitted] • Bismuth ferrite polymorphism composites (BFPCs) driven photo-Fenton system at λ >420 nm. • The LED/BFPCs/H 2 O 2 system show high efficiency with saving H 2 O 2 (85%) and reaction time (50%). • Crystal-phase restructuring in BFPCs for enhancing Fe3+/Fe2+ circulation in Fenton chemistry was observed. • BFPCs crystal micro-structure was evaluated by atomic-resolution HAADF imaging with EDS mapping. • The azoxystrobin (AZX) degradation pathway in LED/BFPCs/H 2 O 2 system is proposed for the first time. Emerging organic pollutants (EOPs), such as azoxystrobin (AZX) fungicide, have been an increasingly serious problem in aquatic environments. Here, a novel Fe/Bi-nanocrystal (bismuth ferrite polymorphism composites, BFPCs) driven a new photo-Fenton system in visible light (λ >420 nm) irradiation (LED/BFPCs/H 2 O 2) remarkably accelerates hydroxyl radical (HO•) formation with excellent efficiencies of both AZX and other 18 EOPs (especially for AZX 100 % degradation rarely reported). The system outperforms in mineralization rate, saving H 2 O 2 usage (85 %) and reaction time (50 %) compared to the alike Fenton-like system. A phenomenon in BFPCs crystal structure observed on the crystal phase transformation from FeO 6 octahedron into FeO 4 tetrahedron that implied/uncovered a new finding of crystal-phase restructuring for enhancing Fe3+/Fe2+ circulation in Fenton chemistry. The stability of crystal structure and chemical composition of BFPCs catalysts was evaluated by HAADF imaging coupling with EDX mapping at atomic level. The mechanism on AZX degradation pathway in LED/BFPCs/H 2 O 2 system is proposed for the first time by monitoring HO• and its source, and intermediates at a control condition. [ABSTRACT FROM AUTHOR]

This study aims to explore the reusability of wastewater treatment by-product for photo-Fenton process to treat an organic pollutant model. The optimal condition, reactive oxygen species (ROS), and kinetic approach in photo-Fenton process was discussed. The Metal oxide crystal pellets from are a by-product of the Fluidized-Bed Crystallization (FBC) process and can be used as a catalyst in the Photo-Fenton process. Electroplating wastewater containing iron and copper was treated via the FBC process using granulated Al(OH) 3 as carrier seeds. The binary oxide of FeOOH and Cu 2 O on the Al(OH) 3 surface (Fe 0.66 Cu 0.33 @Al(OH) 3) was identified as the FBC by-product after characterization using FTIR and XPS analysis. In the photo-Fenton process, visible light from a fluorescence lamp with a wavelength of 400–610 nm was chosen as an irradiation source. Oxalic acid was added as chelating agent to form photosensitive iron oxalate species and hydrogen peroxide was applied as oxidant to generate active radical to decolorize and mineralize RB5 synthesized solution (100 mg/L). The operating conditions including the oxalic acid to pollutant ratio ([OA] 0 /[RB5] 0) of 4.5–13.0, reaction pH (pHr) of 3–7 and initial to theoretical hydrogen peroxide molar ratio [H 2 O 2 ] 0 /[ H 2 O 2 ] theoretical of 35%–120% were optimized. Under the optimal conditions, pH r = 5.0; [H 2 O 2 ] 0 /[RB5] 0 at 75% stoichiometric and [OA] 0 /[RB5] 0 = 9, the RB5 is almost completely decolorized after 210 min of operation and the mineralization efficiency is 58%. The contribution of •OH, O 2 •-, and O 2 1 to the Photo-Fenton system was determined using ESR analysis with the addition of DMPO and TEMP as spin trap agents. The kinetic analysis reveals the observed rate constants k RB5 , k OA and k R from fitting are 0.0120, 0.0054 and 0.0001 M−1s−1, respectively. [Display omitted] • The binary oxide of by-product from FBC process is useful for organics treatment. • Treatability of azo dye RB5 by visible light-assisted photo-Fenton was investigated. • RB5 was completely degraded and mineralized of 55% using a 75% stoichiometric dosage of H 2 O 2 with the addition of oxalic acid at pH 5. • Up to 55% of TOC was mineralized mainly by O 2 •- and O 2 1. • Rate modeling of RB5 and TOC removal were explained using consecutive kinetics. [ABSTRACT FROM AUTHOR]

Abstract Refined natural Fe-chromite was characterized by XRD, FT-IR, reflected polarized microscope, XRF and UV spectrophotometer. Photocatalytic degradation and photo-Fenton oxidation of Congo red dye by Fe-chromite was investigated using 1 mL H2O2. The degradation of dye was studied as a function of illumination time, chromite mass, initial dye concentration, and pH. Fe-chromite acts as binary oxide system from chromium oxide and ferrous oxide. Thus, it exhibits photocatalytic properties under UV illumination and photo-Fenton oxidation after addition of H2O2. The degradation in the presence of H2O2 reached the equilibrium stage after 8 h (59.4%) but in the absence of H2O2 continued to 12 h (54.6%). Photocatalytic degradation results fitted well with zero, first order and second order kinetic model but it represented by second order rather than by the other models. While the photo-Fenton oxidation show medium fitting with the second order kinetic model only. The values of kinetic rate constants for the photo-Fenton oxidation were greater than those for the photocatalytic degradation. Thus, degradation of Congo red dye using chromite as catalyst is more efficient by photo-Fenton oxidation. Based on the response surface analysis, the predicted optimal conditions for maximum removal of Congo red dye by photocatalytic degradation (100%) were 12 mg/l, 0.14 g, 3, and 11 h for dye concentration, chromite mass, pH, and illumination time, respectively. Moreover, the optimum condition for photo-Fenton oxidation of dye (100%) is 13.5 mg/l, 0.10 g, 4, and 10 h, respectively.

Abstract The removal of meropenem and ceftriaxone antibiotics from solution, as first study, was performed in a photo-Fenton process in which UV light and ferrous ions (Fe2+) were applied as persulfate (PS) activators. The batch tests were performed in various conditions like pH of aqueous solution (2−10), amounts of ferrous (0.1–0.5 g/L), initial antibiotic concentrations (20–100 mg/L), persulfate dosages (1–5 mM), UV light intensities (4, 6 and 8 W), temperatures (20, 35 and 50 °C) and scavengers (TBA and IBA). Based on the results of comparative studies, PS/Fe2+/UV system showed the highest ability to remove both antibiotics, in comparison with the other processes (i.e., UV, PS, PS/UV and PS/Fe2+). In addition, the removal rate of antibiotics has a direct relationship with the iron and PS concentrations, UV light intensity and temperature. While, increasing pH of solution and initial antibiotic concentrations, the removal rate of antibiotics witnessed a significant decline. Quenching tests indicated that sulfate radicals had a dominant species during degradation reactions. The mineralization higher than >54% was obtained for both antibiotics. A slight loss was observed in the degradation efficiencies of antibiotics in binary system, compared to the single one. The experimental data were in good agreement with pseudo-first-order kinetic model. Biodegradability indices were enhanced significantly after treatment, which demonstrates that PS/Fe2+/UV system has a high ability in removing organic matters effectively. Finally, it can be inferred that the integration of ferrous ions and UV irradiations was an appropriate technique for efficient activation of PS, which can be introduced as a promising method to remove high concentrations of antibiotics in a real wastewater sample which shows its high feasibility in natural environment. Highlights • Ferrous ions-activated persulfate was coupled with UV irradiation for the antibiotics degradation. • A slight loss was observed in the degradation efficiencies of antibiotics in binary system, compared to the single one. • Quenching tests depicted that both OH and SO 4 − radicals participate during degradation mechanism. • Over 97% of antibiotics were removed by PS/Fe2+/UV system within 60 min reaction. [ABSTRACT FROM AUTHOR]

The beet sugar industry generates large volumes of wastewater with high levels of chemical oxygen demand (COD) and color content, which are discharged into the nearby environment without adequate treatment. The aim of this study was to investigate the treatment possibility of this wastewater by using the photo-Fenton oxidation combined with a coagulation process. Central composite design and response surface methodology were used to evaluate the relationships between color and COD reduction and the photo-Fenton oxidation parameters (i.e. Fenton's reagent dosage, pH, and reaction time). The combined treatment results showed 59% of COD and 83.9% of color removal were obtained at optimum conditions (pH: 6.2; Fe2+ dosage: 20 ppm; H2O2 dosage: 1500 ppm; and reaction time of 15 min). Finally, the results of gel permeation chromatography showed that low molecular weight fraction of the wastewater impurities is more degraded than high molecular weight fraction during oxidation/coagulation process. Therefore, the results obtained from this study showed that an appropriate combined method for the treatment of beet sugar industry wastewater can be designed and implemented. [ABSTRACT FROM AUTHOR]

The yeast production industry wastewaters contains high amount of chemical oxygen demand (COD), brownish color and recalcitrant organic components. In this work, one of the yeast production plant wastewaters operating in the Aegean Region, the color removal were studied with using Photo-Fenton (H2O2/Fe(II)/UV) oxidation processes. In this study, the Box-Wilson statistical experimental design method applied to optimization of decolorisation of the yeast production industry wastewater. For this reason, the initial oxidant and catalyst concentrations and pH of water were chosen as the experimental parameters on decolorisation. Color removal was observed during the experimental studies. Complete color removal (E=100%) was achieved with the addition of 2400 mg/L H2O2 and 121 mg/L Fe(II) at 3.7 pH after 120 min. of exposure to the UV irradiation. [ABSTRACT FROM AUTHOR]

Wastewater management has become crucial for sustaining biological life in the near future. One of the key aspects is integration of treatment processes aiming reuse of treated water for many purposes instead of water discharge. This study focused on combining two different methods, photo-Fenton-like oxidation, and adsorption, for treatment of real textile wastewater to improve water quality to be reused for irrigation. The real textile wastewater was collected from a local plant and subjected to photo-Fenton-like oxidation and adsorption as hybrid process. The operational parameters were optimized for each step by assessing the water quality according to the domestic regulations for irrigation water. The photo-Fenton-like oxidation itself was not successful to achieve the targeted water quality for reuse whereas adsorption as an additional step made the treated water reusable in terms of organic content. But the treated water still contained a certain amount of salinity due to extreme salt usage in textile processing. It was concluded that the treated water at the end of hybrid process could be used for salinity resistant plants such as sugar beet, barley, and cotton which demonstrates a promising contribution to the circular economy for biomass. [Display omitted] • Corncob was valorized for real industrial wastewaters to be reused for irrigation. • Photo-Fenton-like oxidation was effective to satisfy most of the water quality parameters. • Adsorption was the polishing step for removal of organics at low concentrations. • Treated water can be used to irrigate many plants as a part of circular bio-economy. [ABSTRACT FROM AUTHOR]

• PVDF composite membrane was fabricated by loading β-FeOOH nanorods and CQDs. • The membrane can efficiently separate various oil-in-water emulsions. • It has stable underwater superoleophobicity and high photo-Fenton efficiency. • The membrane exhibits excellent anti-oil fouling performances. Oil fouling makes serious trouble to the membranes for oil-in-water emulsion separation and purification. Here, an anti-oil fouling membrane was designed and constructed by loading β-FeOOH nanorods and carbon quantum dots (CQDs) on the poly(vinylidene fluoride)/poly(2-hydroxyethyl methacrylate) blend membrane. The fabricated BM@(β -FeOOH/CQDs) membrane can efficiently separate various oil-in-water emulsions. Furthermore, BM@(β -FeOOH/CQDs) exhibits stable underwater superoleophobicity with an underwater oil contact angle (UWOCA) of 152.5 ± 1.1° and a sliding angle (SA) of 2.2 ± 0.2°, which is beneficial to prevent oil droplets from contacting and adhering to the separation porous surface. Moreover, BM@(β -FeOOH/CQDs) has excellent photo-Fenton oxidation efficiency, which can photo-activate H 2 O 2 to degrade oil droplets on the separation membrane. The flux recovery ratio of the membrane increases by 1.8 times when the photo-Fenton reaction was activated. This work provides an effective strategy for the engineering of anti-oil fouling membranes to purify oily wastewater. [ABSTRACT FROM AUTHOR]

Adsorption and photo-Fenton processes were used as handy tools to ascertain the capability of natural clays to remove cadmium (Cd) and 2-chlorophenol (2-CP) from aqueous solution. Natural Fe-rich clay collected from Tejera-Esghira in Medenine area, south Tunisia, was used as a catalyst in the heterogeneous photo-Fenton oxidation of 2-CP in aqueous solution. Clay samples were acid activated to improve their adsorptive capacity for the removal of Cd. Experimental results indicated that the adsorption of Cd ions onto natural red clay of Tejera-Esghira followed the pseudo-second-order kinetic model. Langmuir model was found to describe the equilibrium data with the calculated maximum adsorption capacity of 23.59 mg g −1 for acid-activated clay. Photo-Fenton experiments proved high activity of the natural clay catalyst, which was able to completely degrade the phenol present in the treated solution after 30 min and in the presence of ultraviolet light C (UV-C). Total organic carbon and gas chromatography analysis confirmed a 2-CP degradation mechanism toward an almost complete mineralization of the organic compound. [ABSTRACT FROM AUTHOR]

Refined natural Fe-chromite was characterized by XRD, FT-IR, reflected polarized microscope, XRF and UV spectrophotometer. Photocatalytic degradation and photo-Fenton oxidation of Congo red dye by Fe-chromite was investigated using 1 mL HO. The degradation of dye was studied as a function of illumination time, chromite mass, initial dye concentration, and pH. Fe-chromite acts as binary oxide system from chromium oxide and ferrous oxide. Thus, it exhibits photocatalytic properties under UV illumination and photo-Fenton oxidation after addition of HO. The degradation in the presence of HO reached the equilibrium stage after 8 h (59.4%) but in the absence of HO continued to 12 h (54.6%). Photocatalytic degradation results fitted well with zero, first order and second order kinetic model but it represented by second order rather than by the other models. While the photo-Fenton oxidation show medium fitting with the second order kinetic model only. The values of kinetic rate constants for the photo-Fenton oxidation were greater than those for the photocatalytic degradation. Thus, degradation of Congo red dye using chromite as catalyst is more efficient by photo-Fenton oxidation. Based on the response surface analysis, the predicted optimal conditions for maximum removal of Congo red dye by photocatalytic degradation (100%) were 12 mg/l, 0.14 g, 3, and 11 h for dye concentration, chromite mass, pH, and illumination time, respectively. Moreover, the optimum condition for photo-Fenton oxidation of dye (100%) is 13.5 mg/l, 0.10 g, 4, and 10 h, respectively. [ABSTRACT FROM AUTHOR]

In this study, we compared the performances of three iron-containing crystalline and amorphous catalysts, that is, Fe-Zeo-A, Fe-ZSM-5, and Fe-silica, respectively, for the degradation of phenol in an aqueous solution. Catalytic activity for the degradation of phenol was assessed by heterogeneous photolysis, Fenton, and photo-Fenton oxidation. All catalysts exhibited higher activity in the photo-Fenton process. In addition, the catalyst stability was evaluated by the estimation of the iron loss and structural variations after the oxidation processes. Results revealed that Fe-silica and Fe-ZSM-5 exhibit higher catalytic activity (~100% phenol removal), while only 64% of phenol removal over Fe-Zeo-A was observed. Moreover, among all catalysts, Fe-ZSM-5 exhibited higher stability with low iron leaching, attributed to the uniform distribution of bonded Fe in the crystalline framework and narrow channels. On the contrary, amorphous Fe-silica exhibited higher iron leaching due to the presence of isolated iron species in the structure, leading to the partial involvement of a homogeneous reaction during the degradation of phenol. The structural stability of Fe-based catalysts was examined using microscopic and spectroscopic techniques.

Trimethoprim is one of the representative drugs within the pharmaceutical and personal care products (PPCPs) group. The photo-Fenton oxidation technology was used to degrade trimethoprim in wastewater and the extent of degradation was analyzed by using high-performance liquid chromatography, then experimentally obtained the optimal conditions. Analysis of the experimental data showed that, under the single-factor experimental conditions, the optimal conditions for degradation were a pH of 4, an H2O2 concentration of 3.0 mmol/L, an FeSO4 concentration of 0.06 mmol/L, an initial trimethoprim concentration of 0.0689 mmol/L, and an ultraviolet (UV) intensity (UVA) of 12 mW/cm2. The interaction of pH and the concentration of H2O2 and Fe2+ have been further explored, it was obtained the following response surface results through the central composite design experiment: pH = 4.56, H2O2 concentration = 0.09 mmol/L, and Fe2+ concentration = 0.09 mmol/L. Under these conditions, it can be obtained a degradation rate of 99.95% after 6 min. There were similar results for three sets of parallel experiments, indicating that these simulation conditions were feasible.

In this study, α-FeOOH on reduced graphene oxide (rGO-α-FeOOH) supported on an Al-doped MCM-41 catalyst (RFAM) was optimized for the visible-light photo-Fenton oxidation of phenol at neutral pH. The stability of the catalysts, effect of bubbling aeration, and degradation intermediates were investigated. Results indicated that RFAM with a large Brunauer-Emmett-Teller (BET) area and mesoporous structure displayed excellent catalytic activity for the visible-light-driven (VLD) photo-Fenton process. Phenol degradation was well described by a pseudo-first-order reaction kinetics model. Raman analysis demonstrated that an rGO-α-FeOOH (RF) composite is formed during the ferrous-ion-induced self-assembly process. Al-MCM-41 could uniformly disperse RF nanosheets and promote the mobility and diffusion of matter. The activity of the main catalyst α-FeOOH was enhanced after the incorporation of rGO nanosheets. The α-FeOOH crystal in RFAM showed catalytic activity superior to those of Fe 3 O 4 and Fe 2 O 3 . The RFAM catalyst, with an optimal GO-Fe 2+ mass ratio of 2.33, exhibited a larger BET area, pore size, and pore volume, and thus exhibited high performance and energy utilization efficiency in the VLD photo-Fenton reaction with remarkable stability. Bubbling N 2 inhibited catalytic performance, while bubbling O 2 or air only slightly accelerated the phenol degradation. Visible light played an important role in accelerating the formation of reactive oxygen species (·OH) for the highly efficient phenol degradation. Analysis of degradation intermediates indicated a high phenol mineralization level and the formation of low-molecular-weight organic acids. This work would be helpful in providing an insight into a new type of catalyst assembly and a possible route to a promising heterogeneous catalyst applicable in the visible light photo-Fenton process for effective wastewater remediation at neutral pH. [ABSTRACT FROM AUTHOR]

The post-treatment of biodigested sugarcane vinasse was envisaged in the present study following three different approaches: i) coagulation/flocculation – Approach 1; ii) combination of coagulation/flocculation with photo-Fenton reaction – Approach 2; iii) coagulation/flocculation followed by biological degradation and photo-Fenton reaction – Approach 3. The coagulation/flocculation per se provided a slight increase in effluent's biodegradability, a decrease in toxicity and turbidity, and provided moderate removals of total organic carbon (TOC), biochemical oxygen demand (BOD 5 ) and chemical oxygen demand (COD). The operating costs associated with chemicals consumption are low (5.7 R$/m 3 ≈ 1.4 €/m 3 ). The second and third treatment approaches allowed to reach a nontoxic effluent, improved the biodegradability and led to similar high global organics removal efficiencies. The combined treatment consisting of coagulation/flocculation plus photo-Fenton oxidation (Approach 2) revealed to be a promising solution for treating this wastewater, in order to be recirculated into the high rate anaerobic reactor. Additionally, this solution provides smaller costs (84.9 R$/m 3 ≈ 20.2 €/m 3 ) associated with chemicals and energy consumption, which are however very high. Nonetheless, this cost can be reduced by about 40% if solar radiation is used in the photo-Fenton process. [ABSTRACT FROM AUTHOR]

The degradation of ethylparaben using photo-Fenton-like oxidation was investigated in the presence of a BiFeO3 catalyst. Firstly, the catalyst was synthesized using the sol-gel method and characterized via BET and FT-IR analyzes and then, a parametric study was carried out in order to determine the optimum reaction conditions for the degradation of ethylparaben. In this context, the effects of catalyst loading, [H2O2]°, pH, and temperature on the degradation were investigated. According to the results, the optimum reaction conditions were determined for a 5 ppm ethylparaben solution as 0.25 g/L catalyst loading, a pH of 3, and 2 mM [H2O2]° and a 97.7% degradation of ethylparaben was accomplished. Iron leaching at the optimum conditions was evaluated as 1.53 ppm and it is lower than the E.U. iron concentration limitation (2 ppm) in the water. The kinetic study was carried out at the optimum reaction conditions at three different temperatures (25, 35, and 45 °C). The degradation of ethylparaben using photo-Fenton-like oxidation fitted the first order reaction kinetic model. The reaction rate constants were determined as 0.041, 0.050, and 0.069 min-1 for 25, 35, and 45 °C, respectively. The activation energy was found as 20.4 kJ/mol. [ABSTRACT FROM AUTHOR]

Largely limited by the high dissociation energy of the O-O bond, how to effectively promote the activation of molecular oxygen (O 2) on the surface of the graphitic carbon nitride (g-C 3 N 4) has always been the key to improving the photocatalytic performance of g-C 3 N 4. In this study, by utilizing the coordination reaction between F-Fe and O-Fe, a complex (ox-Fe-F-g-C 3 N 4) with F and Fe as central atom, oxalate (ox) and g-C 3 N 4 as ligand molecule was successfully constructed. Relevant characterizations and density functional theory (DFT) calculations together verify that the electron transfer of complex was significantly promoted. It not only beneficial to enhance the ability of photogenerated holes (h+) to directly oxidize tetracycline (TC), but also helps to accelerate the activation of O 2 to generate reactive oxygen species (ROS). In addition, under the action of photoelectron reduction, a photo-Fenton oxidation platform based on Fe (III) and Fe (II) cycling can be established on the surface of F-g-C 3 N 4. This facilitates the conversion of H 2 O 2 generated by activating O 2 into hydroxyl radicals (•OH) with higher oxidative activity. Batch degradation experiments confirmed that under the synergistic promotion of surface coordination and photo-Fenton oxidation, the photocatalytic efficiency of ox-Fe-F-g-C 3 N 4 is nearly 4 times that of pristine g-C 3 N 4. [Display omitted] • Surface double central atom coordination enhances photoelectron transfer. • Organic acid ligand molecule promotes the activation of O 2 to generate ROS. • Photo-Fenton oxidation system accelerates the decomposition of H 2 O 2 into •OH. • Planar structure design and surface charge regulation synergistically boost the photocatalytic efficiency of F-g-C 3 N 4. [ABSTRACT FROM AUTHOR]

In this study, photo-Fenton-like oxidation method was evaluated for synthetic sugar industry wastewater using visible-light driven Cu–BiOI photocatalyst. Reaction conditions including initial pH, catalyst loading, initial hydrogen peroxide (H 2 O 2) concentration, and temperature, were optimized. At these optimized conditions, the total saccharide concentration (TSC) and total organic carbon (TOC) removals were 56.20% and 30.67%, respectively whereas the maximum TSC and TOC removal reached up to 93.35% and 74.72% respectively by decreasing initial sucrose concentration. The kinetic study showed that the reaction order for sucrose and TOC oxidation was determined as 2 for pseudo-homogeneous power law models with respect to sucrose concentration and TOC, respectively.For heterogeneous models, Langmuir-Hinshelwood model based on the mechanism of adsorbed pollutant and oxidant on different catalytic sites was the best fit for oxidation of sucrose and other organic intermediates. According to the catalyst characterization studies, incorporation of copper was successful and Cu–BiOI possesses high photocatalytic activity accomplished by acid-assisted synthesis method. • A greener process was applied for treatment of sugar industry wastewater. • Highest TSC and TOC removals reached 93.35% and 74.72%, respectively. • Catalytic activity of Cu–BiOI was attributed to its unique micro-flower structure. • Oxidation reactions were represented by homogeneous and heterogeneous models. [ABSTRACT FROM AUTHOR]

This investigation compared the performance of Fenton and photo-Fenton oxidation processes in the treatment of sulfidic spent caustic wastewater. Response surface methodology, particularly central composite design was used to investigate the effect of Fe/H2O2 and H2O2/COD in assessing treatment process efficiency. Empirical models were developed to describe the relationship between the factors and responses. The models were validated through analysis of variance and were further used in process optimization. The best solution for Fenton process was found to be at Fe/H2O2 and H2O2/COD ratio of 0.07 and 2.52 correspondingly. On the other hand, lower H2O2/COD ratio of 1.84 was achieved in photo-Fenton process. Removal of COD and sulfide up to 97% and 100% was observed with photo-Fenton process. [ABSTRACT FROM AUTHOR]

Abstract: This work focused on the development and the validation of a mathematical model for the UV-C photo-Fenton degradation of acetic acid using a LaFeO3 heterogeneous structured catalyst with a monolithic structure. A combined study of the evolved gases and the liquid phase was conducted. The experimental results led to the identification of the main reactions that occur in the system: the complete mineralisation of acetic acid by H2O2 due to the presence of the catalyst and the decomposition of H2O2 to water and O2 in the homogeneous phase. A mathematical model was then developed using Eley–Rideal-type kinetics for the acetic acid consumption and first-order kinetics for the photolysis of hydrogen peroxide. The apparent kinetic constants were estimated, and the accuracy of the model was tested under different experimental conditions to evidence the predictive capability of the model. A very good agreement between the mathematical model calculations and the experimental data obtained in the presence of various H2O2 dosages was achieved. The results demonstrate that the continuous addition of H2O2 during the photo-Fenton reaction ensures the fruitful utilisation of the produced hydroxyl radicals in the acetic acid oxidation reaction to minimise the oxidant consumption and maximise the TOC removal in a shorter irradiation time. [Copyright &y& Elsevier]

Olive oil mill wastewater (OMWW), a recalcitrant pollutant, has features including high phenolic content and dark color; thereby, several chemical or physical treatments or biological processes were not able to remediate it. In this study, the treatment efficiencies of three treatments, including adsorption, biological application, and photo-Fenton oxidation were sequentially evaluated for OMWW. Adsorption, biological treatment, and photo-Fenton caused decreasing phenolic contents of 48.69 %, 59.40 %, and 95 %, respectively. However, after three sequential treatments were performed, higher reduction percentages in phenolic (total 99 %) and organic contents (90 %) were observed. Although the studied fungus has not induced significant color reduction, photo-Fenton oxidation was considered to be an attractive solution, especially for color reduction. Besides, toxicity of OMWW treatment was significantly reduced. [ABSTRACT FROM AUTHOR]

Abstract: Clay pillared with Al–Fe was synthesized as a catalyst for (photo)-Fenton oxidation of 4-chlorophenol. The catalyst was characterized by X-ray diffraction, nitrogen physisorption, diffuse reflectance UV–VIS spectroscopy and temperature-programmed reduction. The chemical composition, indicating the incorporation of Al and Fe within the clay structure, was determined by ICP-OES. The oxidation of 4-chlorophenol was faster in the UV-A assisted process, followed by VIS-light assisted and “dark” processes. All the processes begin with an induction period, followed by a fast oxidation step. Iron leaching is observed for all the systems and was mainly attributed to proton and reductive dissolution processes. Proton dissolution is very slow and could be responsible for the induction period. The reductive dissolution is induced in the presence of 4-chlorocatechol, the main reaction intermediate. The dissolved iron ions are able to catalyze the homogeneous Fenton-like process. All the experimental findings suggest that a combined heterogeneous–homogeneous mechanism could be envisaged for the studied reaction system. [Copyright &y& Elsevier]

Abstract: The treatment efficiency of aniline wastewater by single photo-Fenton, single biological oxidation and combined photo-Fenton and biological oxidation were compared. The effect of different factors, such as pH, Fe2+ and H2O2 concentrations on degradation efficiency were investigated. Effective degradation of aniline wastewater have been observed by photo-Fenton process, but complete mineralization of aniline wastewater need to consume large numbers of H2O2, so the single photo-Fenton oxidation is uneconomical technology. The aniline wastewater is less biodegradable and very toxic to microorganisms, the removal efficiency are low by direct biological oxidation. The toxicity of the aniline wastewater was found to be reduced obviously after pretreatment by the photo-Fenton oxidation. The combined photo-Fenton and biological oxidation was an effective treatment technology for toxic aniline wastewater. Experimental results showed that 62.5% of H2O2 were saved by combined photo-Fenton and biological oxidation processes, comparing with single photo-Fenton process. [Copyright &y& Elsevier]

For the treatment of paracetamol in water, the UV-C Fenton oxidation process and classic Fenton oxidation have been found to be the most effective. Paracetamol reduction and chemical oxygen demand (COD) removal are measured as the objective functions to be maximized. The experimental conditions of the degradation of paracetamol are optimized by the Fenton process. Irifluent pH 3, initial H2O2 dosage 60 mg/L, 1H2O2]/[Fe2+] ratio 60:1 are the optimum conditions observed for 20 mgIL initial paracetamol concentration. At the optimum conditions, for 20 mg/L of initial paracetamol concentration, 82% paracetamol reduction and 68% COD removal by Fenton oxidation, and 91% paracetamol reduction and 82% COD removal by UV-C Fenton process are observed in a 120 mm reaction time. By HPLC analysis, 100% removal of paracetamol is observed at the above optimum conditions for the Fenton process in 240 mm and for the UV-C photo-Fenton process in 120 mm. The methods are effective and they may be used in the paracetamol industry. [ABSTRACT FROM AUTHOR]

Abstract: In this work photo-Fenton oxidation of acetic acid, was carried out on perovskites based structured catalysts, in the presence or in the absence of low amounts of Pt. Homogeneous photo-Fenton reaction by ferrioxalate complex has been also performed. The comparison of homogeneous and heterogeneous photo-Fenton oxidation indicates that the use of a heterogeneous structured catalyst greatly improves the total organic carbon (TOC) removal and leads to a more effective use of H2O2. The rate of TOC removal during the runtime decreased because of the occurring side H2O2 decomposition to O2 that subtracts the oxidant to the photo-Fenton reaction. Moreover it allows enlarging the pH range of operation without the formation of sludge or significant metal leaching. LaFeO3 and Pt/LaMnO3 resulted the best catalysts for this process in terms of reaction rate. [Copyright &y& Elsevier]

The article discusses the study which explores the efficiency of various methods including biological, enzymatic, and photo-Fenton oxidation on reducing the phenols in olive oil mill wastewater (OOMW). It notes the application of liquid-liquid extraction and gas chromatography-mass spectrometry on examining the samples. Moreover, photo-Fenton treatment successfully removed the phenol supplements.

Abstract: Olive oil mill wastewater (OOMW) is responsible for serious environmental problems. In this study, the efficiency of two treatments involving fungi and photo-Fenton oxidation, sequentially applied to OOMW was analyzed for organic compounds degradation and toxicity mitigation. The treatment with fungi (especially Pleurotus sajor caju) of diluted OOMW samples promoted a reduction of their acute toxicity to Daphnia longispina. Although this fungi species have not induced significant color reduction it was responsible for 72,91 and 77% reductions in chemical oxygen demand (COD), total phenolic and organic compound contents. After biological treatment, photo-Fenton oxidation seemed to be an interesting solution, especially for color reduction. However, the OOMWs remained highly toxic after photo-Fenton oxidation. Considering the second sequence of treatments, namely photo-Fenton oxidation followed by biological treatment, the former revealed, once more, a great potential because it can be applied to non-diluted OOMW, with significant reductions in COD (53–76%), total phenolic content (81–92%) and organic compounds content (100%). Despite fungal species still have demonstrated a high capacity for bioaccumulation of organic compounds, resulting from photo-Fenton oxidation, the biological treatment did not cause substantial benefits in terms of COD, total phenolic content and toxicity reduction. [Copyright &y& Elsevier]

Abstract: Visible light-assisted photo-Fenton-like oxidation of a mono-azo textile dye, acid red 88 (AR88), has been carried out in the presence of Co2+ as the catalyst and peroxomonosulphate (PMS) as the oxidant. Decolorization of AR88 in the Co2+/PMS system was observed to follow zero-order kinetics with respect to the dye. It was also found that the decolorization of AR88 increased as the concentration of cobalt ions was increased. The rate of abatement of the acid red 88 was found to be independent of the concentrations of dye and oxidant (PMS). Mineralization studies were also carried out by monitoring the reduction in total organic carbon (TOC) content during the course of the reaction and a suitable mechanism has been proposed. [Copyright &y& Elsevier]