Enhancing disinfection and microcontaminant removal by coupling LED driven UVC and UVA/photo-Fenton processes in continuous flow reactors.

For the first time, the sequential combination of UVC-LED (276 nm) and photo-Fenton/UVA-LED (376 nm) process has been assessed in continuous flow mode for wastewater reclamation according to the new European Regulation for reuse in agricultural irrigation (EU 2020/741). The results show that it is possible to obtain water quality class B (Escherichia coli ≤ 100 CFU/100 mL) by UVC-LED irradiation alone, operating the system with a hydraulic residence time (HRT) of 6.5 min and liquid depth of 5 cm in the case of secondary effluents with low Escherichia coli load (8.

Influence of water matrix components and peroxide sources on the transformation products and toxicity of tebuthiuron under UVC-based advanced oxidation processes.

Coupling of UV-C irradiation to different peroxides (HO, SO and HSO) has great potential to degrade persistent organic compounds due to the formation of HO or SO species. However, an in-depth comparison between the performance of different UV-C/peroxide processes as a function of (i) target compound degradation, (ii) generated transformation products and (iii) lethal/sub lethal toxicity effects has not yet been performed. To this end a comparison study was carried out to evaluate the effectiveness of different UV-C/peroxide processes using the herbicide tebuthiuron (100 or 500 μg L) as a model pollutant.

Effect of Iron Complex Source on MWWTP Effluent Treatment by Solar Photo-Fenton: Micropollutant Degradation, Toxicity Removal and Operating Costs.

Benzophenone-3, fipronil and propylparaben are micropollutants that are potential threats to ecosystems and have been detected in aquatic environments. However, studies involving the investigation of new technologies aiming at their elimination from these matrices, such as advanced oxidation processes, remain scarce. In this study, different iron complexes (FeCit, FeEDTA, FeEDDS and FeNTA) were evaluated for the degradation of a mixture of these micropollutants (100 µg L−1 each) spiked in municipal wastewater treatment plant (MWWTP) effluent at pH 6.

A review toward contaminants of emerging concern in Brazil: Occurrence, impact and their degradation by advanced oxidation process in aquatic matrices.

This work presents data regarding the occurrence and treatment of Contaminants of Emerging Concern (CECs) in Brazil in the past decade. The literature review (2011-2021) revealed the detection of 87 pharmaceutical drugs and personal care products, 58 pesticides, 8 hormones, 2 illicit drugs, caffeine and bisphenol A in distinct matrices (i.e.

Reducing toxicity and antimicrobial activity of a pesticide mixture via photo-Fenton in different aqueous matrices using iron complexes.

This is the first study to investigate ethylenediamine-N,N'-disuccinic acid (EDDS)/photo-Fenton process to polish real wastewater containing pesticides for possible water reuse. To this end, simultaneous degradation of pesticides ametrine, atrazine, imidacloprid and tebuthiuron was evaluated in distilled water (DW) and in sewage treatment plant (STP) effluent at initial pH 6.0.

Chemical and toxicological evaluation along with unprecedented transformation products during photolysis and heterogeneous photocatalysis of chloramphenicol in different aqueous matrices.

As the presence of antibiotics in environmental waters enhances antimicrobial resistance, photolysis and heterogeneous photocatalysis of chloramphenicol (CAP) were evaluated in deionized water (DW) and in sewage treatment plant (STP) effluent under black light and solar irradiation. Processes were compared in terms of CAP degradation, reaction kinetics, and electrical energy per order, as well as regarding theoretical toxicity, biodegradability, carcinogenicity, and mutagenicity of transformation products (TPs). Rate constants obtained under photolysis (0.

Degradation mechanism of fipronil and its transformation products, matrix effects and toxicity during the solar/photo-Fenton process using ferric citrate complex.

This study presents the degradation of fipronil in sewage treatment plant (STP) effluent by photo-Fenton at near neutral pH (pH 6.0) using Fe/Citrate complex. 83% of fipronil degradation was reached using a molar iron/citrate ratio of 1:3 (192 μmol L of Fe/576 μmol L of citrate).

Design of an industrial solid waste processing line to produce refuse-derived fuel.

Municipal Solid Waste (MSW) from the city of Boa Esperança, Minas Gerais, Brazil, was used to produce refuse-derived fuel (RDF). The MSW contains residues from human society, including product packaging, bottles, batteries, organic waste, fines, textiles, health textiles, plastics, glass, and metals, among others. The following protocol was performed during the conversion of MSW to RDF: (i) the raw MSW was placed in a silo and sent to a primary crusher using a metal conveyor belt, which reduced the particle size to 80 mm; (ii) the biomass was transferred to a selective waste collection platform by a rubber conveyor belt, and the recyclable waste, metals, and glasses were separated manually; (iii) residual metals were removed by a magnetic separator; (iv) the waste was transferred to a secondary crusher which reduced the particle size to 60 mm; (v) the waste passed through an airborne separator to remove materials with high density, such as glass, stones, and organic materials, using a metallic conveyor belt; (vi) the particle size was reduced to 40 mm by a tertiary crusher; (vii) the aluminium was separated from the non-metallic materials (plastic, paper, rubber, etc.

Correlation between pH and molar iron/ligand ratio during ciprofloxacin degradation by photo-Fenton process: Identification of the main transformation products.

Ciprofloxacin has been determined with high frequency in studies involving environmental waters matrixes. However, no study evaluating the correlation between the initial pH and molar iron/organic ligand ratio has been published. This paper describes the degradation of the antibiotic ciprofloxacin by the photo-Fenton process using different sources of iron (Fe, Fe and Fe-citrate and Fe-oxalate, named FeCit and FeOx, respectively) and molar iron/organic ligand ratios at initial pH values of 2.

Integrating coagulation-flocculation and UV-C or HO/UV-C as alternatives for pre- or complete treatment of biodiesel effluents.

The feasibility of biodiesel effluent treatment combining coagulation-flocculation with a photolytic process was evaluated, being the photolytic process involving the irradiation of the effluent by UV-C, or by UV-C irradiation with simultaneous addition of HO (HO/UV-C). The coagulation-flocculation was performed at the natural pH of the effluent (pH 2.9) using different Fe salts (chloride, nitrate and sulfate) at different concentrations (0.

Optimization of fipronil degradation by heterogeneous photocatalysis: Identification of transformation products and toxicity assessment.

In this work it was studied the degradation of the insecticide fipronil (FIP) by heterogeneous photocatalysis induced by TiO P25. Using chemometric methods (Factorial Design and Response Surface Methodology), it was possible to evaluate the role of interaction between pH of the reaction medium, the reaction time and concentration of TiO, optimizing the conditions for degradation using artificial radiation. Under the optimized conditions (79.

Degradation of Direct Red 81 mediated by Fenton reactions: multivariate optimization, effect of chloride and sulfate, and acute ecotoxicity assessment.

The role of different operational parameters related to Fenton reactions (pH, concentration of Fe and HO, and reaction time) and of Cl and SO was investigated in the degradation of the azo dye Direct Red 81, expressed in terms of its decolorization. The factorial design and Pareto's charts showed that only Fe concentration and pH influence the decolorization under the conditions evaluated. So, only these parameters were optimized using the response surface model.

Coupling coagulation, flocculation and decantation with photo-Fenton process for treatment of industrial wastewater containing fipronil: Biodegradability and toxicity assessment.

This work reports the treatment of wastewater containing the insecticide fipronil, integrating coagulation, flocculation and decantation in the photo-Fenton process. Under the best concentration of the coagulant - Fe(3+) (56 mg L(-1)), the suspended solids and total fipronil concentrations decreased respectively from 7000 and 20.9 mg L(-1) to 590 and 2.

Paracetamol degradation intermediates and toxicity during photo-Fenton treatment using different iron species.

The photo-Fenton degradation of paracetamol (PCT) was evaluated using FeSO(4) and the iron complex potassium ferrioxalate (FeOx) as iron source under simulated solar light. The efficiency of the degradation process was evaluated considering the decay of PCT and total organic carbon concentration and the generation of carboxylic acids, ammonium and nitrate, expressed as total nitrogen. The results showed that the degradation was favored in the presence of FeSO(4) in relation to FeOx.

Degradation of caffeine by photo-Fenton process: optimization of treatment conditions using experimental design.

The degradation of caffeine in different kind of effluents, via photo-Fenton process, was investigated in lab-scale and in a solar pilot plant. The treatment conditions (caffeine, Fe(2+) and H(2)O(2) concentrations) were defined by experimental design. The optimized conditions for each variable, obtained using the response factor (% mineralization), were: 52.

Degradation of the antibiotic amoxicillin by photo-Fenton process--chemical and toxicological assessment.

The influence of iron species on amoxicillin (AMX) degradation, intermediate products generated and toxicity during the photo-Fenton process using a solar simulator were evaluated in this work. The AMX degradation was favored in the presence of the potassium ferrioxalate complex (FeOx) when compared to FeSO(4). Total oxidation of AMX in the presence of FeOx was obtained after 5 min, while 15 min were necessary using FeSO(4).

Photodegradation of sulfamethoxazole in various aqueous media: persistence, toxicity and photoproducts assessment.

The photochemical transformation of sulfamethoxazole (SMX) was investigated in different water matrices: distilled water (DW), distilled water+nitrate (10 and 20 mg L(-1)) and seawater (SW) to evaluate its persistence, toxicity and degradation pathway. A solar simulator Suntest CPS+ was used for the irradiation experiments. Identification of transformation products was performed in DW by liquid chromatography-time of flight-mass spectrometry (LC-TOF-MS).

Soil remediation using a coupled process: soil washing with surfactant followed by photo-Fenton oxidation.

In the present work the use of a coupled process, soil washing and photo-Fenton oxidation, was investigated for remediation of a soil contaminated with p,p'-DDT (DDT) and p,p'-DDE (DDE), and a soil artificially contaminated with diesel. In the soil washing experiments, Triton X-100 (TX-100) aqueous solutions were used at different concentrations to obtain wastewaters with different compositions. Removal efficiencies of 66% (DDT), 80% (DDE) and 100% (diesel) were achieved for three sequential washings using a TX-100 solution strength equivalent to 12 times the effective critical micelle concentration of the surfactant (12 CMC(eff)).

Degradation of sulfamethoxazole in water by solar photo-Fenton. Chemical and toxicological evaluation.

In this work, the photocatalytic degradation of the antibiotic sulfamethoxazole (SMX) by solar photo-Fenton at pilot plant scale was evaluated in distilled water (DW) and in seawater (SW). Degradation and mineralization of SMX were strongly hindered in SW compared to DW. The influence of H(2)O(2) and iron concentration on the efficiency of the photocatalytic process was evaluated.

Environmental implications of soil remediation using the Fenton process.

This work evaluates some collateral effects caused by the application of the Fenton process to 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) and diesel degradation in soil. While about 80% of the diesel and 75% of the DDT present in the soil were degraded in a slurry system, the dissolved organic carbon (DOC) in the slurry filtrate increased from 80 to 880mgl(-1) after 64h of reaction and the DDT concentration increased from 12 to 50microgl(-1). Experiments of diesel degradation conducted on silica evidenced that soluble compounds were also formed during diesel oxidation.

Treatment of 1,10-phenanthroline laboratory wastewater using the solar photo-Fenton process.

The red Fe(2+)-phenanthroline complex is the basis of a classical spectrophotometric method for determination of iron. Due to the toxicity of this complexing agent, direct disposal of the wastewaters generated in analytical laboratories is not environmentally safe. This work evaluates the use of the solar photo-Fenton process for the treatment of laboratory wastewaters containing phenanthroline.

Evaluation of the influences of solution path length and additives concentrations on the solar photo-Fenton degradation of 4-chlorophenol using multivariate analysis.

This study reports the photodegradation of 4-chlorophenol (4-CP) in aqueous solution by the photo-Fenton process using solar irradiation. The influence of solution path length, and Fe(NO(3))(3) and H(2)O(2) concentrations on the degradation of 4-CP is evaluated by response surface methodology. The degradation process was monitored by the removal of total organic carbon (TOC) and the release of chloride ion.

Solar photodegradation of dichloroacetic acid and 2,4-dichlorophenol using an enhanced photo-Fenton process.

The photo-Fenton process using potassium ferrioxalate as a mediator was investigated for the photodegradation of dichloracetic acid (DCA) and 2,4-dichlorophenol (DCP) in aqueous medium using solar light as source of irradiation. The influence of the solution depth, the light intensity and the effect of stirring the solution during irradiation process were evaluated using DCA as a model compound. A negligible influence of stirring the solution was observed when the concentration of ferrioxalate (FeOx) was 0.