photo-Fenton Method Research Articles

A performance comparison of photo-fenton decolorization of methylene blue by using bentonite/iron composites prepared by liquid phase and solid phase ion exchange method

Nowadays, there is a wide range of pollutants present, which requires the treatment of wastewater. The photo-Fenton method has been recognized as valuable in this area. In this study, iron/bentonite composites were created using both liquid phase and solid phase iron exchange techniques, and they were utilized as a photocatalyst for the degradation of methylene blue through photo-Fenton process. Various factors affecting the photocatalytic decolorization were investigated, including the initial concentration of the dye, weight of the catalyst, pH of the solution, and concentration of hydrogen peroxide. The decolorization efficiency of the iron/bentonite composites prepared using the solid phase and liquid phase ion exchange approaches was found to be 99% and 95%, respectively. Based on the data, it can be concluded that the performance of both catalysts was almost equally influenced by the initial dye concentration, catalyst weight, solution pH, and hydrogen peroxide concentration. Moreover, the solid phase ion exchange method demonstrated greater reusability compared to the liquid phase ion exchange method. Consequently, it can be stated that the solid phase ion exchange approach is a suitable and straightforward alternative to the conventional liquid phase ion exchange method for producing a photo-Fenton catalyst.

Preparation of the photo-Fenton agent MIL-100 (Fe) with high performance in the degradation of nitro explosives

Layered MIL-100 (Fe) can almost completely degrade nitro explosives within 2 min by the photo-Fenton method.

Tertiary Wastewater Treatment Technologies: A Review of Technical, Economic, and Life Cycle Aspects

The activated sludge process is the most widespread sewage treatment method. It typically consists of a pretreatment step, followed by a primary settling tank, an aerobic degradation process, and, finally, a secondary settling tank. The secondary effluent is then usually chlorinated and discharged to a water body. Tertiary treatment aims at improving the characteristics of the secondary effluent to facilitate its reuse. In this work, through a literature review of the most prominent tertiary treatment methods, a benchmarking of their technical efficiency, economic feasibility, and environmental impact was carried out. The photo-Fenton method proved to be the most technically efficient process, significantly reducing the microbial load and pharmaceutical content (by 4.9 log and 84%, respectively) of the secondary effluent. Chlorination and UV irradiation exhibited the lowest treatment costs (0.004 EUR/m−3) and the lowest global warming potential (0.04 and 0.09 kg CO2eq. m−3, respectively). After all the data were aggregated, a decision-making tool was constructed in the form of a ternary diagram, which indicates the most appropriate tertiary treatment method according to the weight-per-process aspect (technical, economic, and environmental) selected by the user, with chlorination, UV irradiation, ozonation, microalgae cultivation, and constructed wetlands prevailing in the final results.

Optimization Approach to Evaluate the Solar, UV and LED Visible Light Fenton Processes for Pollutant Degradation in Landfill Leachate

<p>In the current study, three different photo-assisted sources were used to evaluate the photo-Fenton oxidation process for the pollutant degradation of mature landfill leachate. Solar, UV, and LED visible light photo sources were adopted in this Fenton process. Fenton dosages (FeSO4 : H2O2) 1:30, 1.5:30, 2:30, and 2.5:30g/L were used in the investigation, which was conducted under a variety of pH settings (2 to 3.5) and at experimental reaction duration of 30, 60, 90, and 120 minutes. To analyze and compare the efficiency of the solar, UV, and LED visible light photo Fenton processes for pollutant degradation, Taguchi experimental design orthogonal arrays (L16) was employed. To analyse the significance of this experimental design for landfill leachate treatment, Larger the Better was selected. The highest levels of pollutant degradation in the Solar Photo Fenton method was identified when compared to UV, and LED visible light photo Fenton processes. The maximum removal of 95% color, 83% COD, 89% TSS, 94% Cr, 86% Cd, and 93% Cu was achieved in Solar Photo Fenton process at pH-3, Fenton dosage 1.5:30 g/L and reaction period 60 minutes.</p>

Synthesis, characterization, and photocatalytic applications of novel sword-like copper oxide microparticles

• Novel CuO microparticles in sword-like morphology were prepared by microemulsion and calcination. • The major composition of the prepared materials was confirmed by XRD and EDS. • The photocatalytic property of the CuO microparticles was established using methylene blue model dye compound. • The degradation of methylene blue dye followed first-order kinetic model according to the general Langmuir–Hinshelwood mechanism. This letter aimed to synthesize novel copper oxide (CuO) microparticles via the microemulsion method followed by calcination. The synthesized material was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffractometry, and diffuse reflectance spectroscopy techniques; and subsequently applied for the degradation of methylene blue (MB) using the heterogeneous photo-Fenton method. SEM images revealed the formation of homogeneous sword-like CuO microparticles. The XRD pattern and EDS spectrum confirmed that the main part of the material was CuO with the formation of Na 8 Cu 5 O 10 as an impurity. The photocatalytic degradation of MB followed the first-order kinetic model according to the general Langmuir–Hinshelwood mechanism. The as-prepared materials can be successfully applied in the visible-light-induced photocatalytic degradation of hazardous organic compounds and industrial wastewaters.

Influence of the Local Structure on the Photocatalytic Properties of Zinc Spinel Ferrite Nanoparticles

The correlation between iron distribution in octahedral or tetrahedral sites in synthetic magnetite and zinc spinel ferrites and their catalytic properties were investigated in this work. The zinc-doped nanomagnetites were prepared by co-precipitation method and annealed at 420 °C. X-ray diffraction, UV-Vis, X-ray absorption and 57Fe Mössbauer spectroscopies were used to identify iron sites. The obtained results showed that ZnII replaces the relatively smaller FeIII cation in the tetrahedral sites, increasing the cubic lattice dimension, and this replacement remarkably enhances the catalytic effectiveness of the Zn-spinel ferrite towards the indigo carmine degradation compared to undoped magnetite. The indigo carmine degradation experiments were carried out using photo-Fenton method in which 50 mL of indigo carmine dye aqueous solutions (20 mg L−1, pH 3.0), 20 mg ZnxFe(3-x)O4, and 2.0 mL H2O2 (aqueous solution at 0.028 mol L−1) were placed under UV light at 25 °C. Under these experimental conditions the degradation rate of indigo carmine was superior to 98%.

Detoxification of As(III) in Aqueous Media by Using Photo-Fenton Method

<p>In this paper, photo-Fenton method has been systematically examined to oxidize the toxic and mobile As(III) in the solution by •OH radicals resulted from the reactions between Fe2+ and H2O2 under UV light, to form the less toxic and insoluble As(V). The effects of various experimental parameters including initial Fe2+ and H2O2 concentrations, working pH, and contact time were studied through a batch experiment. The concentration of As(V) resulted from the photo-oxidation was determined by visible spectrophotometry method based on the formation of arsenate molybdate solution. The results of the research attributed noticeably that the As(III) could be oxidized through photo-Fenton process to form As(V) that was assigned by a considerable decline in the concentration. The maximal oxidation of As(III) with 10 mg L-1 of the concentration in 50 mL of the aqueous solution, that was about 85%, can be reached in the presence of Fe2+ 10-2 mole L-1, H2O2 5. 10-2 mole L-1 at the working pH 3 and within 3 h of the reaction time. It has been also detected that for reaching the permissible level (lower than 0.01 mg L-1 ), three stages of the photo-Fenton process were required.</p>

Investigation the effect of intensity and direction of light on the removal of reactive blue dye from simulated wastewater using photo-Fenton oxidation under UV irradiation: Batch and continuous methods

This study aims to remove reactive blue dye (R.B) from simulated wastewater by utilizing advanced oxidation processes (AOPs) using a photo-Fenton (UV/H2O2/Fe+2) system. A photo-reactor containing four fixed UV lamps had been employed in a batch and continuous mode under the effect of several operating variables (dosage of H2O2; dosage FeSO4; pH; temperature; irradiation time). Response surface methodology (Box–Behnken design) and Portable Statgraphics Centurion statistical software were used to design the experiments and conducting the mathematical correlation of the required responses as well as the interaction effects among variables. The optimal conditions of the operating variables; dosage hydrogen peroxide, ferrous sulphate, pH, temperature and irradiation time were 78 ppm, 20 ppm, 3, 40°C and 90 min, respectively which give 84.82% of removal efficiency. Then, the effect of light intensity and distance from a UV source were studied at optimum conditions in the batch photo-reactor where the highest dye removal efficacy was obtained at a light intensity of 24 w and a distance of 15cm. For continuous system, two operating conditions were studied, the direction of the light radiation and the flow rate which proofed that the dye removal efficiency decreased with an increase of flow rate and the top direction compared to the side direction of the light where the removal percentage of (R.B) was 100% for the flow rate of 10 ml/min while it was 84.16% for a flow rate of 50 ml/min. The results show that the photo-Fenton method is an effective treatment method of Wastewater containing dyes.

Ag2O and NiO Decorated CuFe2O4 with Enhanced Photocatalytic Performance to Improve the Degradation Efficiency of Methylene Blue.

Dye wastewater is a serious threat to human health and life. It is an important task for researchers to treat it efficiently. Among many treatment methods, the photo-Fenton method can rapidly degrade organic pollutants. In this study, a ternary photocatalyst, Ag2O-NiO/CuFe2O4, was prepared and applied for a photo-Fenton reaction to degrade methylene blue (MB). MB had the best degradation effect when 10 mg of the catalyst were used in an 80 mL reaction system for measurement. The degradation rate of MB was up to 96.67% in 60 min with a high degradation rate constant . The total organic carbon (TOC) degradation rate was 78.64% with a TOC degradation rate constant of . Therefore, this study fully proves that Ag2O-NiO/CuFe2O4 can catalyze the photo-Fenton reaction and effectively degrade MB.

Treatment of Synthetic Wastewater Containing Diethyl Phthalate through Photo-Fenton Method by Box-Behnken Design

Background & Aims of the StudyDiethyl phthalate (DEP) cannot be proficiently degraded by ultraviolet (UV) radiation and hydrogen peroxide (H2O2) oxidation separately; however, the photo-Fenton method is verified to be operative and can completely degrade this pollutant. Currently, advanced oxidation methods have been growing to be employed for the remediation of industrial wastewater. In the present study, the photo-Fenton process investigated the degradation and mineralization of the aqueous solution containing DEP.Materials and MethodsSynthesized wastewater was used in this study. In addition, the effects of operative factors, such as the initial concentrations of H2O2, ferrous ion, and DEP, have been studied. The response surface methodology and Box-Behnken design of experiments were applied to examine the effects of three sovereign variables on the response functions to obtain the optimum circumstances.ResultsThe analysis of variance was carried out to determine the importance of the effects of independent variables on the response function. Various amounts of variables were optimized for the removal of DEP. At optimum conditions (i.e., H2O2 concentration of 400 mg/l, ferrous concentration of 75 mg/l, and DEP concentration of 50 mg/l) and 60 min following the reaction, the rates of degradation efficiency for DEP and chemical oxygen demand (COD) were 100% and 85.3%, respectively.ConclusionAccording to the obtained results, the suggested quadratic model showed good correctness. The statistical analysis of the model indicated that the model was satisfactory to predict the performance of the processes. The obtained findings demonstrated that the photo-Fenton processes can be used for the complete and partial removal of DEP and COD from wastewater, respectively. The benefits of the photo-Fenton process were less sludge formation, fewer chemicals, and time obligation but at the cost of consumed power. The power consumption can be reduced by employing sunlight instead of artificial UV light to a larger amount. The photo-Fenton procedure was influential in the degradation of DEP and can considerably decrease COD.

Kajian Metode foto-Fenton untuk Penurunan Konsentrasi Ion Logam Berat Pb(II) dan Cu(II) dalam Larutan Secara Simultan dan Sinergi

To prevent an environmental pollution by hazardous heavy metals, in the present study, a simulatenous decrease of the concentration of Pb((II) and Cu(II) in the solution by photo-Fenton method has been systematically studied. Photo-Fenton process proceeded in a close reactor by batch technique. The process was conducted by exposure solutions containing Pb(II) and Cu(II) ions, and Fenton’s reagent (Fe2+ and H2O2) under UV-A lamp. In this study, the initial concentations of Pb(II) and Cu(II), and the exposure time were optimized. The synergyc effect that may be appeared on the decrease of Pb(II) and Cu(II) ion concentrations simultaneously through photo-Fenton process was also addressed. The concentrations of Pb(II) and Cu(II) in the solution were determined by AAS. The research results exhibited that photo-Fenton process could decrease Pb(II) and Cu(II) concentrations, and the maximum decreases, 46.12 % dan 16.86% for Pb(II) and for Cu(II) respecticely, were found by applying both initial concentration of Pb(II) and Cu(II) as much 35 mg/L, and 60 min of the time. The concentration decreases of Pb (II) and Cu(II) were results of oxidation by OH and by electron to form PbO2 and Cu particles respectively as probed by EDX data. Furthermore, photo-Fenton process toward a solution containing Pb(II) and Cu(II) ions allowed oxidation of Pb(II) and reduction of Cu(II) simultaneously and showed a synergic effect. Such effect was demonstrated by the fact that the presence of Cu(II) ion in the photo-Fenton process of Pb(II) solution could improve the Pb(II) oxidation and the highest improvement of Pb(II) oxidation (81.06%) was shown by 35 mg/L of the Cu(II) concentration. Similarly, the presence of Pb(II) in the photo-Fenton process of Cu(II) solution could enhance the reduction of Cu(II), and the highest effect on the Cu(II) reduction enhancement was exhibited by 35 mg/L of the Pb(II) concentration.

Solar photo-Fenton reagent with nanostructured iron oxide for Bismarck dye oxidation: an Egyptian apparel case study

In this study, the oxidation of textile effluent containing Bismarck dye (BD) has been carried out via a cost-efficient and eco-friendly heterogeneous photo-Fenton method under natural solar radiations as well as artificial UV source. Hematite nanocrystals that were successfully prepared using a simple sol-gel approach were tested for use as a catalyst in the Fenton process. X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscope techniques were applied to investigate the structural and morphological properties of these nanocrystals. The results showed that the material had a better photocatalytic activity under sunlight irradiation. The process of solar photo-Fenton reagent including nanocrystals was found to be competent for the oxidation of BD compared with the process of using artificial UV irradiations. The oxidation was improved to a great extent from 23 to 60% removal in the treatment time of 60-min irradiation. The dye load increase in wastewater results in a low oxidation rate. The key factor is containing 40 and 400 mg L−1 of hematite nanocrystals and H2O2, respectively, at pH 3.0. Further, the temperature increases increment the reaction rate. The oxidation process follows pseudo-second-order kinetics with activation energy of 1.3 kJ mol−1. Thus, the practical application of such nanocrystals on the Fenton system using natural UV radiation on the real textile effluent signifies that process is highly efficient for a safer environment.

Remediation efficiency of different methods for rapid-response of microbiological and/or organic matter contaminated beach sand: A laboratory study

In this article we compare the efficiency of different methods of rapid-response remediation of beach sand contaminated with microbiological and/or organic matter. Contaminated beach sands were treated in laboratory by different treatment methods (i.e., oxidation, UV-photoexposure, or thermal methods) and the efficiency of disinfection and breakdown of organic matter were evaluated. Contaminants in raw and treated beach sands were measured by membrane filtration method, and by chemical and biochemical oxygen demand, and chromatographic analysis. All the methods tested were efficient for disinfecting beach sand with microbiological contamination, except for the UV-photoexposure method, which showed only moderate disinfection potential. Chemical degradation efficiency of beach sand contaminated by crude petroleum was higher with Fenton and Photo-Fenton (associated with the use of surfactant and ultrasound) methods. Photo-Fenton method improvement can increase the efficiency of contaminated beach sand treatment, and can also help beach managers when selecting which method to adopt for remedial actions.

Removal of Pb (II) Ions in The Aqueous Solution by Photo-Fenton Method

<p>Photo-Fenton for decreasing concentration of Pb(II) ions in the aqueous solution is systematically studied. The photo-Fenton process was carried out by batch technique, under UV light. The influences of process operating parameters were evaluated. The results of the research demonstrated that by photo-Fenton process, the concentration of Pb(II) ions in the aqueous solution can be decreased, that may be through oxidation mechanism by OH radicals. The decrease is found to be controlled by Fe2+ and H2O2 concentrations, as well as by the pH and the irradiation time. For 20 mg/L of Pb(II) in the 100 mL solution, the optimum condition of the oxidation is obtained to be 10 mmole/L of Fe2+, 200 mmole/L of H2O2, pH 3, and 90 min of the reaction time. It is also confirmed that the oxidation of Pb (II) by OH radical has formed the undissolved PbO2, that is less toxic and easier to be handled.</p>

Treatment of oil refinery wastewater by photo-Fenton process using Box–Behnken design method: kinetic study and energy consumption

Nowadays, advanced oxidation processes (AOPs) are receiving increasing attention to be used for industrial wastewater treatment. In this study, the wastewater of Shazand Oil Refinery Company in Iran was treated using photo-Fenton method as a branch of AOPs. Box–Behnken design was used to reduce the number of tests and to conduct the statistical analysis of the results. The aim of this study was to reduce the chemical oxygen demand (COD) of industrial wastewater and obtain the optimum condition in the removal of COD. For this purpose, the effects of operating factors such as hydrogen peroxide concentration (10–30 mM), iron ion concentration (0.7–2.1 mM), and pH (2–6) were investigated. The results of the analysis of variance showed that the operating parameters were effective. The initial COD of industrial wastewater was about 3400 mg l−1, and in the achieved optimum conditions, approximately 75% of initial COD was removed and the amounts of other parameters such as biological oxygen demand (BOD), total organic carbon (TOC), and total dissolved solid were reduced significantly. The BOD5 to COD ratio of the treated wastewater was increased considerably. Moreover, the kinetic study revealed pseudo-first-order reactions for the removal of COD. Accordingly, as a figure of merit, the “electrical energy per order” was determined at 25.04 kWh m−3 order−1, showing low electrical energy consumption and high economical profit in comparison with high COD removal.

Improved biodegradability of hardly-decomposable wastewaters from petrochemical industry through photo-Fenton method and determination of optimum operational conditions by response surface methodology

BackgroundPetrochemical wastewaters are highly polluting due to having various destructive materials such as aromatic hydrocarbons and heavy metal ions. Therefore, they need to be treated before disposal to the environment. However, due to low biodegradability, applying common treatment methods such as activated sludge is not feasible for these wastewaters.MethodsPhoto-Fenton is an advanced oxidation process which was applied to promote the biodegradability of hardly-decomposable petrochemical wastewaters. The wastewater samples were provided by Maroon and Karoon petrochemical plants, located in Mahshahr, Iran. To design the experiments and analyze the experimental results, response surface method with four variables (input COD and TDS concentrations and injected a dosage of H2O2 and Fe2+) and four fixed parameters (temperature, pH, retention time, and UV power) were used.ResultsThe ranges of input COD, H2O2, Fe2+ and TDS were 1000 to 2500 mg L− 1, 1000 to 4000 mg L− 1, 500 to 3000 mg L− 1, and 4500 to 11,500 mg L− 1, respectively. Average input BOD5/COD ratio was 0.09. These ranges and values were determined according to the quality of the raw wastewater and experimental design. Output BOD5/COD ratio was varying between 0.3 and 0.6, which declined with an increase of input COD. The results showed that the biodegradability of the industrial wastewater was promoted upon application of higher H2O2 and Fe2+ concentrations. Meanwhile, TDS concentration had no significant effect on biodegradability of this wastewater. The following optimum conditions were resulted by evaluating the maximum efficiency of the reactor in enhancing the biodegradability of the wastewater: 1000 mg L− 1 input COD, 2668 mg L− 1 H2O2, 1655 mg L− 1 Fe2+, 8000 mg L− 1 TDS, 0.6 output BOD5/COD, 852 mg L− 1 output BOD5 and 939 mg L− 1 output COD.ConclusionPhoto-Fenton method is highly efficient for increasing the biodegradability of petrochemical wastewaters before applying biological wastewater treatment.

Organic pollutant degradation of tapioca flour industrial waste with photo-fenton reaction

Cassava (Manihot utilissima) is the main raw material of tapioca flour industry. The tapioca industry waste water still contains high enough BOD, COD, and cyanide, above the quality standard of industrial waste water. Photo-Fenton is one of the most effective alternative methods of degrading organic pollutants. This study aims to determine the effect of Photo-Fenton method on the degradation of organic pollutants such as COD and cyanide. For operating conditions of this study use the addition of concentrations of H2O2 and FeSO4.7H2O and different UV light intensity. The analysis of COD concentration using SNI method is spectrophotometric. From the research result, it is found that the concentration of COD and cyanide in tapioca waste can be reduced by using Photo-Fenton method. With initial COD content of 6000 mg/L and cyanide level of 0.67 mg/L. And in the operating conditions of the addition of 5 ml/l of H2O2, Fe2+ 1.25 mg/l, and light intensity of 200 lm, the highest COD and cyanide levels were found to be 900 mg/l for COD and 0.08 mg/l for cyanide. Final levels of COD up to 900 mg/l and cyanide concentrations up to 0.08 mg/l.

Experimental and theoretical study on degradation of oxidized C60 in water via photo-Fenton method

With popular application of fullerene (C60) and its derivative in functional materials, they have been discharged into water. Therefore, it is urgent to develop an effective and environmentally friendly method for removing C60 and its derivative from water. However, an efficient method of degradation of C60 and its derivative in water hasn’t been reported. C60 in water can be oxidized by light to give oxidized C60 (OC60), therefore, degradation of OC60 plays a key role in removal of C60 and its derivative in water. In this paper, OC60 was effectively degraded via photo-Fenton method to give carbon dioxide and H2O. The degradation process was monitored by ultraviolet–visible absorption spectroscopy, X-ray diffraction and scanning electron microscopy. Degradation intermediates were determined by Fourier transform infrared spectroscopy, liquid chromatography-tandem mass spectrometry, and elemental analysis. Density functional theory calculations were used to study the mechanism of hydroxyl radical reaction. Based on experimental data and Gaussian calculations, degradation mechanism of OC60 in water was proposed.

Removal of phosphonates from industrial wastewater with UV/FeII, Fenton and UV/Fenton treatment

Phosphonates are an important group of phosphorus-containing compounds due to their increasing industrial use and possible eutrophication potential. This study involves investigations into the methods UV/FeII, Fenton and UV/Fenton for their removal from a pure water matrix and industrial wastewaters. It could be shown that the degradability of phosphonates by UV/FeII (6 kWh/m3) in pure water crucially depended on the pH and was higher the less phosphonate groups a phosphonate contains. The UV/FeII method is recommended in particular for the treatment of concentrates with nitrogen-free phosphonates, only little turbidity and a low content of organic compounds. Using Fenton reagent, the degradation of polyphosphonates was relatively weak in a pure water matrix (<20% transformation to o-PO43–). By means of the Photo-Fenton method (6 kWh/m3), those phosphonates with the smallest numbers of phosphonate groups were easier degraded as well at pH 3.5 in a pure water matrix (o-PO43– formation rates of up to 80%). Despite an incomplete transformation of organically bound phosphorus to o-PO43– with Fenton reagent in an organically highly polluted wastewater (max. 15%), an almost total removal of the total P occurred. The most efficient total P elimination rates were achieved in accordance with the following Fenton implementation: reaction → sludge separation (acidic) → neutralization of the supernatant → sludge separation (neutral). Accordingly, a neutralization directly after the reaction phase led to a lower total P removal extent.

Degradation of oxidized multi-walled carbon nanotubes in water via photo-Fenton method and its degradation mechanism

With popular application of multi-walled carbon nanotubes (MWCNTs), they have been discharged into water. MWCNTs and their derivatives may harm organs, cells and organisms. Therefore, development of an efficient method for removing MWCNTs and their derivatives from water is important. Under UV–light irradiation, MWCNTs can be oxidized by oxygen in air to give oxidized MWCNTs (O-MWCNTs), therefore, degradation of O-MWCNTs is a vital step for removal of MWCNTs and their derivatives from water. In this paper, O-MWCNTs were degraded via photo-Fenton method to give CO2 and water after 168h. Degradation process was detected by total organic carbon and ultraviolet–visible absorption spectra. Degradation intermediates were supposed based on nuclear magnetic resonance, liquid chromatography-tandem mass, Raman, fourier transform infrared spectra and elemental analysis data. In order to develop an efficient degradation method for removing O-MWCNTs from water, photodegradation mechanism of O-MWCNTs was suggested.