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Ethyl‐parathion (EP) is a globally‐distributed organophosphorus (OP) pesticide where environmental release is a standard use case. The present study sought to determine if sunlight degraded EP and if the degraded products were toxic to biological molecules in cell‐free assays. A 24 mg/L solution of EP (water solubility limit) was exposed to direct sunlight for 0, 1, 2, 3 and 4 hrs where as much as 64.6 % of EP was degraded relative to the 0 hr sunlight exposure. Singlet oxygen formation (1O2) increased by 15.9, 20.6, 29.8, and 64.4 % in the 1, 2, 3 and 4 hr sunlight exposures, respectively. Ultra‐high performance liquid chromatography further confirmed the sunlight‐induced transformation of EP and the increased 1O2 formation through time, likely via a type‐II photochemical mechanism. The degradation of DNA nucleotides (8‐hydroxy 2‐deoxyguanosine), the formation of superoxide anion radical (O2.‐) which was validated by significant O2.– quenching by superoxide dismutase (SOD), and peroxidation of membrane lipid (linoleic acid), increased significantly in sunlight exposures, however the presence of EP at 24 mg/L had no significant influence on this effect. Overall, sunlight quickly degraded EP in solution, however the sunlight‐irradiated EP caused no discernable toxic effects in cell‐free assays relative to sunlight alone. [ABSTRACT FROM AUTHOR]

Aminophosphonate diethylenetriamine penta(methylenephosphonic acid) (DTPMP) is a scale inhibitor commonly used in several industries. DTPMP is suspected to cause anthropogenic pollution through discharge into the aquatic environment. DTPMP is assumed to be degraded by sunlight radiation. We recently predicted a preliminary degradation pathway of DTPMP applying UV treatment. Currently, we have not yet evidenced that DTPMP shows the same degradation pattern with natural sunlight. One major reason leads to the fact that the light spectrum emitted by UV lamps does not completely represent the natural sunlight spectrum, and the emitted UVB and UVA irradiation flux is much higher than for solar light. For that reason, the degradation pattern and kinetics might be different between artificial UV treatment and natural sunlight treatment. Here, we investigated whether DTPMP is degradable under natural sunlight radiation, and whether the degradation mechanisms determined through UV treatment are transferable to sunlight. We investigated five different treatment conditions, i.e., DTPMP degradation in direct or diffuse sunlight, in diffuse sunlight with addition of Ca2+ or Mg2+, and in diffuse sunlight with local TW. Our experiment was carried out from March 2021 to October 2021. We performed LC/MS analyses and measured the release of o-PO43−. DTPMP was degraded with all five treatment conditions. The fastest DTPMP degradation occurred in direct and diffuse sunlight without addition of bivalent cations. The addition of Ca2+ and Mg2+ resulted in inhibited degradation. Similar effects occurred for sunlight treatment with local TW. We evidenced different degradation mechanisms for DTPMP depending on the presence of alkaline earth metals as we previously proposed for UV-treated DTPMP. However, both degradation mechanisms of DTPMP belong to the same degradation pathway determined with UV treatment. Therefore, we conclude that DTPMP undergoes a similar degradation pathway in sunlight as compared to UV light. [ABSTRACT FROM AUTHOR]

To enhance the effectiveness of TiO2 as a photocatalyst, it was believed that the drawbacks of the large bandgap and the rapid electron-hole recombination can be overcome by coupling TiO2 with plasmonic metal nanoparticles. The incorporation of the nanoparticles onto the TiO2 surface requires a suitable procedure to achieve the proper particle adhesion. In this work, we propose a simple, clean, and effective surface activation of TiO2 using plasma enhanced wet chemical surface treatment. Under only 5 min of plasma treatment in a 3% NH3/3% H2O2 solution, gold nanoparticles were found better adhered onto the TiO2 surface. Hence, the methylene blue degradation rate of the Au/TiO2 under sunlight treated was improved by a factor of 3.25 times in comparison to non-treated Au/TiO2 and by 13 times in comparison to the bare rutile TiO2. [ABSTRACT FROM AUTHOR]

To enhance the effectiveness of TiO2 as a photocatalyst, it was believed that the drawbacks of the large bandgap and the rapid electron-hole recombination can be overcome by coupling TiO2 with plasmonic metal nanoparticles. The incorporation of the nanoparticles onto the TiO2 surface requires a suitable procedure to achieve the proper particle adhesion. In this work, we propose a simple, clean, and effective surface activation of TiO2 using plasma enhanced wet chemical surface treatment. Under only 5 min of plasma treatment in a 3% NH3/3% H2O2 solution, gold nanoparticles were found better adhered onto the TiO2 surface. Hence, the methylene blue degradation rate of the Au/TiO2 under sunlight treated was improved by a factor of 3.25 times in comparison to non-treated Au/TiO2 and by 13 times in comparison to the bare rutile TiO2.

Titanium dioxide is the most used photocatalyst in wastewater treatment; its semiconductor capacity allows the indirect production of reactive oxidative species. The main drawback of the application of TiO2 is related to its high band-gap energy. The nonmetal that is most often used as the doping element is nitrogen, which is due to its capacity to reduce the band-gap energy at low preparation costs. There are multiple and assorted methods of preparation. The main advantages and disadvantages of a wide range of preparation methods were discussed in this paper. Different sources of N were also analyzed, and their individual impact on the characteristics of N⁻TiO2 was assessed. The core of this paper was focused on the large spectrum of analytical techniques to detect modifications in the TiO2 structure from the incorporation of N. The effect of N⁻TiO2 co-doping was also analyzed, as well as the main characteristics that are relevant to the performance of the catalyst, such as its particle size, surface area, quantum size effect, crystalline phases, and the hydrophilicity of the catalyst surface. Powder is the most used form of N⁻TiO2, but the economic benefits and applications involving continuous reactors were also analyzed with supported N⁻TiO2. Moreover, the degradation of contaminants emerging from water and wastewater using N⁻TiO2 and co-doped TiO2 was also discussed.

Hexadecyltrimethylammonium-bromide-activated zeolite nanoparticles coated with copper sulfide (ZEO/HDTMA-Br/CuS) was evaluated as a photocatalyst under sunlight for the degradation of metronidazole (MET). The surface and structural characteristics of ZEO/HDTMA-Br/CuS and other materials used in this study were analyzed using field emission-scanning electron microscopy, Fourier transform infrared and ultraviolet–visible diffuse reflectance spectroscopies, X-ray diffraction, Brunauer–Emmett–Teller surface area and Barrett–Joyner–Halenda pore size and volume analyses, and pH of zero charge test. ZEO/HDTMA-Br/CuS exhibited excellent surface and structural catalytic properties. For a comprehensive study of the degradation process, several parameters, such as the pH (3–11), MET concentration (10–30 mg/L), ZEO/HDTMA-Br/CuS dose (0.005–0.1 g/L), reaction time (5–200 min), and H 2 O 2 concentration (50–200 mg/L), were optimized. ZEO/HDTMA-Br/CuS achieved 100% degradation efficiency when 10 mg/L MET was used under the optimum conditions: pH = 7, ZEO/HDTMA-Br/CuS dose = 0.01 g/L, and reaction time = 180 min. The degradation efficiency increased when the concentration of H 2 O 2 was increased from 50 to 150 mg/L and decreased with further increase to 200 mg/L, indicating that the efficiency of MET degradation highly depends on the concentration of H 2 O 2 in an aqueous solution. The degradation kinetics analysis revealed that the degradation is of the pseudo first-order. Thus, ZEO/HDTMA-Br/CuS proved to be an exceptional catalyst for the photodegradation of MET in aqueous media. [Display omitted] • Photocatalytic degradation of metronidazole using sunlight is demonstrated. • Surfactant- and CuS-activated zeolite nanoparticles was used as a photocatalyst. • The used photocatalyst was an efficient and highly stable photocatalyst. • Under optimum conditions, 100% degradation of metronidazole was achieved. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Z-type heterojunction Bi 12 O 15 Cl 6 @W 18 O 49 @g-C 3 N 4 /PDI with a dual-channel charge transport pathway was constructed. • Full spectrum of light source could be utilized for photocatalytic removal of phenols by Bi 12 O 15 Cl 6 @W 18 O 49 @g-C 3 N 4 /PDI. • A localized surface plasmon resonance effect in photocatalysis was observed. A novel plasmonic Bi 12 O 15 Cl 6 @W 18 O 49 @g-C 3 N 4 /PDI photocatalyst with dual charge transfer paths was prepared via a solvothermal method using W 18 O 49 nanowires grown on Bi 12 O 15 Cl 6 nanosheets, followed by loading graphitic carbon nitride/ pyromellitic acid dianhydride (g-C 3 N 4 /PDI) onto the resulting Bi 12 O 15 Cl 6 @W 18 O 49 via simple calcination. The heterojunction displayed outstanding photocatalytic performance in the degradation of bisphenol A (BPA) under simulated sunlight illumination, achieving an efficiency of 100% with respect to the removal of BPA (10 ppm) within 30 min. The results of five recycling experiments and an X-ray diffraction analysis before and after degradation showed that the photocatalyst had a relatively stable structure and properties. The investigation of the mechanism regarding the enhanced activity of the plasmonic photocatalyst revealed that dual charge transfer paths and the localized surface plasma resonance effect significantly improved the photogenerated electron transport efficiency and light absorption capacity of the Bi 12 O 15 Cl 6 @W 18 O 49 @g-C 3 N 4 /PDI composite, which can effectively activate molecular oxygen, producing superoxide radicals and hydroxyl radicals. This study provides a novel platform for the application of the localized surface plasmon resonance effect in photocatalysis via the development of a photocatalyst with dual charge transfer paths. [ABSTRACT FROM AUTHOR]

Flotation wastewater discharged directly into the environment may lead to pollution and ecological damage. The adsorption capacity, neutralization and settling ability of modified fly ash could be greatly improved to adsorb heavy metals and neutralize acidity from flotation wastewater. Under the conditions of pH 7-11, lead ions =50 mg/L, zinc ions =50 mg/L, copper ions = 50 mg/L, the effluent quality treated by modified fly ash could reach lead ions <1mg/L, zinc ions <1mg/L, and copper ions <0.5 mg/L. With a long period of sunlight irradiation, CODcr could be degraded slowly but the functional groups of flotation reagents could not be changed. Biological aerated filter (BAF) process uses a spherical light weight aggregate as filter material to treat flotation wastewater. With the following raw water quality (pH 6-8, CODcr = 300-400 mgfL, DO, HRT, filter material height being controlled), the CODcr removal rate of treated effluent could reach 67.47%. The total effluent quality could reach "Emission Standard of Pollutants for Lead and Zinc Industry (GB-25466-2010)": [ABSTRACT FROM AUTHOR]

Three common disinfectants were selected in this study to investigate their toxicity to Daphnia magna. The methods used in this study included the traditional acute toxicity test, new embryo toxicity test, and teratogenic test. The study concluded that the acute toxicity of the three disinfectants to young daphnids and embryos were hypochlorite > formaldehyde > m-cresol. The effects on growth mostly occurred in the late stages of organogenesis. Of the organs, the Malpighian tube was the most sensitive to disinfectants during embryonic organogenesis. After exposure of the disinfectants to sunlight for 4 h, acute toxicity and teratogenic effects of hypochlorite on young daphnids decreased by 30% and 71%, respectively, while those of formaldehyde decreased by 35% and 49%, respectively. In addition, comparing toxic endpoints of the three disinfectants with and without sunlight exposure, the embryo tests were equally sensitive to the three-week reproduction test in this study. [Copyright &y& Elsevier]

Titanium dioxide is the most used photocatalyst in wastewater treatment; its semiconductor capacity allows the indirect production of reactive oxidative species. The main drawback of the application of TiO2 is related to its high band-gap energy. The nonmetal that is most often used as the doping element is nitrogen, which is due to its capacity to reduce the band-gap energy at low preparation costs. There are multiple and assorted methods of preparation. The main advantages and disadvantages of a wide range of preparation methods were discussed in this paper. Different sources of N were also analyzed, and their individual impact on the characteristics of N–TiO2 was assessed. The core of this paper was focused on the large spectrum of analytical techniques to detect modifications in the TiO2 structure from the incorporation of N. The effect of N–TiO2 co-doping was also analyzed, as well as the main characteristics that are relevant to the performance of the catalyst, such as its particle size, surface area, quantum size effect, crystalline phases, and the hydrophilicity of the catalyst surface. Powder is the most used form of N–TiO2, but the economic benefits and applications involving continuous reactors were also analyzed with supported N–TiO2. Moreover, the degradation of contaminants emerging from water and wastewater using N–TiO2 and co-doped TiO2 was also discussed. [ABSTRACT FROM AUTHOR]