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Soluble bio-based substances (SBO) have been isolated from urban waste. Their structural similarity with natural organic matter suggested exploring their activity in the photodegradation of organic substrates. In this work, they are shown to promote the photodegradation of monochlorophenols. Experiments performed with 1.0 × 10−4 M substrate solutions irradiated by simulated solar light in the presence of SBO showed the progressive degradation of all the probe substrates. The experimental data were fitted to a pseudo-first-order kinetics, and the rate constant was found to decrease in the following order: 2-chlorophenol > 3- chlorophenol > 4-chlorophenol. The effect of pH and SBO concentration on chlorophenols degradation was assessed. Experiments performed in the presence of selective scavengers along with EPR measurements supported the main role of singlet oxygen in the substrate photodegradation mechanism. Toxicity assays showed that the photodegradation of chlorophenols in the presence of SBO is accompanied with a progressive up to complete detoxification of the system. Moreover, no significant contribution of SBO to the whole system toxicity was observed. The results show how urban wastes can be a resource of photosensitizing bio-based substances to be explored in wastewater treatments. ; This work has been partially supported with Italian Ministero delle Politiche Agricole e Forestali funds for the Agrienergia project. The authors are also grateful to 7thFP, IRSES-2010-269128-EnvironBos Marie Curie Action, to Acea Pinerolese Industriale in Pinerolo, TO (Italy), for supplying the sourcing UBW material, and to Studio Chiono and Associati in Rivarolo Canavese, TO (Italy), for making available the pilot equipment for SBO production. ; Avetta, P.; Bella, F.; Prevot, AB.; Laurenti, E.; Montoneri, E.; Arques Sanz, A.; Carlos, L. (2013). Waste cleaning waste: Photodegradation of monochlorophenols in the presence of waste-derived photosensitizer. ACS Sustainable Chemistry & Engineering. 1:1545-1550. ...

[EN] A kinetic-based rationale to assess the role of each excited species in thermodynamically favoured photocatalytic processes at different pollutant concentrations, has been developed and illustrated with new experimental data. Specifically, 2,4,6-triphenylthiapyrylium (TPTP+) salt has been chosen as a representative organic compound capable to act as photocatalyst, and the possible involvement of its excited states in the photodegradation of pollutants commonly found in aqueous ecosystems has been investigated using five chemicals, namely acetaminophen, acetamiprid, caffeine, clofibric acid and carbamazepine. First, steady-state photolysis has been carried out under simulated solar irradiation in the presence of TPTP+, and second, photophysical measurements (fluorescence and laser flash photolysis) have been performed in order to obtain reliable fast kinetic data. Thermodynamic considerations allow ruling out energy transfer processes, while the kinetic results are in good agreement with an electron transfer to the triplet excited state of TPTP+. Hence, the higher the intersystem crossing quantum yield the better. Although quenching of the singlet excited state is also observed, the contribution of this reactive species is only minor, due to its shorter lifetime. In general, the efficiency of a photocatalyst should be enhanced at higher pollutant concentrations, at which the intrinsic decay of the triplet excited state is minimized. (C) 2016 Elsevier B.V. All rights reserved. ; Financial support from Spanish Government (Grants SEV-2012-0267, CTQ2012-38754-C03-03 and CTQ2015-69832-C4-4-R) and Generalitat Valenciana (Prometeo Program) is gratefully acknowledged. R. Martinez-Haya thanks financial support from Spanish Government (Grant SEV-2012-0267). We also thank support from VLC/Campus. ; Martínez-Haya, R.; Gomis, J.; Arques Sanz, A.; Marín García, ML.; Amat Payá, AM.; Miranda Alonso, MÁ. (2017). Time-resolved kinetic assessment of the role of singlet and triplet excited states in the photocatalytic treatment ...

This is the accepted version of the following article: Rodriguez-Muñiz, G. M., Gomis, J., Arques, A., Amat, A. M., Marin, M. L. and Miranda, M. A. (2014), Hydroxyl Radical as an Unlikely Key Intermediate in the Photodegradation of Emerging Pollutants. Photochemistry and Photobiology, 90: 1467–1469, which has been published in final form at http://dx.doi.org/10.1111/php.12325. ; In this work, a kinetic model, in combination with time-resolved experiments, is applied to assess the involvement of OH in the photodegradation of emerging pollutants (EPs) by means of advanced oxidation processes. In contrast with the general assumption, quenching of the short-lived OH in the real waters by the (highly diluted) EPs must be very inefficient, so removal of EPs cannot purely rely on the generation and reaction of OH. This suggests that more complex pathways have to be considered to explain the photodegradation of EPs actually achieved under the employed oxidative conditions, possibly involving other reactive species with longer lifetimes or chain degradation processes. ; This work was supported by the Spanish Government (Projects CTQ2012-38754-C03-03 and CTQ2012-38754-C03-02) and Technical University of Valencia (Predoctoral fellowship for J. Gomis). ; Rodríguez Muñiz, GM.; Gomis Vicens, J.; Arqués Sanz, A.; Amat Payá, AM.; Marín García, ML.; Miranda Alonso, MÁ. (2014). Hydroxyl radical as an unlikely key intermediate in the photodegradation of emerging pollutants. Photochemistry and Photobiology. 90(6):1467-1469. doi:10.1111/php.12325 ; S ; 1467 ; 1469 ; 90 ; 6 ; Farré, M. la, Pérez, S., Kantiani, L., & Barceló, D. (2008). Fate and toxicity of emerging pollutants, their metabolites and transformation products in the aquatic environment. TrAC Trends in Analytical Chemistry, 27(11), 991-1007. doi:10.1016/j.trac.2008.09.010 ; Malato, S., Fernández-Ibáñez, P., Maldonado, M. I., Blanco, J., & Gernjak, W. (2009). Decontamination and disinfection of water by solar photocatalysis: Recent overview and trends. Catalysis ...

[EN] Waste-derived, soluble bin-based substances (SBO), are effective low-cost photosensitizers that could find application in pollutant photodegradation. For this reason, it is important to understand if and to what extent irradiation could modify their properties. The exposure of SBO to simulated sunlight induced important spectral and structural modifications. Both the whole material and its acid-soluble fraction were characterized, highlighting several properties in common with humic and fulvic substances, including absorption spectra, specific absorbance and fluorescence behavior. The latter was described with a three-component model using PARAFAC analysis. Irradiation induced SBO photobleaching, but the absorbance of the acid-soluble fraction increased with irradiation. This finding suggests a progressive photochemical solubilization of SBO, which is confirmed by the increase of the carboxylic groups. In addition to absorbance, the fluorescence of whole SBO was also decreased by irradiation, thereby suggesting that both chromophores and fluorophores were photodegraded. The increasingly hydrophilic character given to SBO by irradiation also accounted for the photoinduced decrease of the surfactant properties of the material. (C) 2015 Elsevier B.V. All rights reserved. ; This work was funded by the 7thFP IRSES-2010-269128-EnvironBos Marie Curie Action and by Ministero delle Politiche Agricole e Forestali (Agrienergia project). The authors are grateful to the following private and/or public Italian institutions: (a) Acea Pinerolese Spa in Pinerolo (TO) for supplying the SBO sourcing materials; (b) Studio Chiono ed Associati in Rivarolo Canavese (TO) for making available pilot equipment and services for the production of the SBO. ; Avetta, P.; Berto, S.; Bianco Prevot, A.; Minella, M.; Montoneri, E.; Persico, D.; Vione, D. (2015). Photoinduced transformation of waste-derived soluble bio-based substances. Chemical Engineering Journal. 274:247-255. https://doi.org/10.1016/j.cej.2015.03.126 ; S ; 247 ; 255 ; 274

[EN] The aim of this work is to determine the photostability biocompatibility and efficiency of water soluble bio-based substances (SBO) in photo-oxidative processes for wastewater treatment. Three batches of SBO, isolated from different sources, have been investigated. Differences in the functional groups present in these substances can explain major trends in their physical/chemical properties. Bioassays have proven those materials to be non-toxic but to show poor biodegradability. Their ability to enhance a photo-Fenton process at milder pH (5.2) has been investigated using a mixture of emerging compounds in wastewaters. All the tested SBO were able to remove all pollutants in less than one hour irradiation, and the best results were obtained with those substances showing higher hydrophilic/hydrophobic ratio. Moreover, although SBOs themselves undergo a slight oxidation, no relevant negative effect has been observed for their use in wastewater treatment. ; The authors want to thank the financial support of the European Union (PIRSES-GA-2010-269128, EnvironBOS) and Spanish Ministerio de Educacion y Ciencia (CTQ2012-38754-C03-02). Juan Gomis would like to thank UPV for his FPI grant (2010-07). ; Gomis, J.; Gonçalves, MG.; Vercher Aznar, R.; Sabater Marco, C.; Castillo López, MÁ.; Prevot, AB.; Amat Payá, AM. (2015). Determination of photostability, biocompatibility and efficiency as photo-Fenton auxiliaries of three different types of soluble bio-based substances (SBO). Catalysis Today. 252:177-183. https://doi.org/10.1016/j.cattod.2014.10.015 ; S ; 177 ; 183 ; 252

The use of soluble bio-based organic substances (SBO) obtained from urban wastes to expand the pH region where the photo-Fenton process can be applied has been investigated in this study. For this purpose, a mixture of six pollutants, namely acetaminophen, carbamazepine, amoxicillin, acetamiprid, clofibric acid and caffeine, at an initial concentration of 5 mg L-1 each, has been employed. Surface response methodology, based on the Doehlert matrix, has shown to be a useful tool to determine the effect of pH (in the range 3-7), concentration of SBO (15-25 mg L-1) and iron (2-6 mg L-1) on the performance of the photodegradation of the studied pollutants, measured by their half-life. Results indicate that, at high SBO concentration, the optimum pH shifts in most cases to a higher value (between 3 and 4) and that a significant loss of efficiency of the process was only observed at pH values above 5. An iron concentration of 4-5 mg L-1 and an amount of SBO of 19-22 mg L-1 have been determined to be the optimal conditions for the degradation of most of the studied pollutants at pH = 5. (C) 2014 Elsevier B.V. All rights reserved. ; The authors want to thank the financial support of the European Union (PIRSES-GA-2010-269128, EnvironBOS) and Spanish Ministerio de Educacion y Ciencia (CTQ2012-38754-C03-02). Juan Gomis would like to thank UPV for his FPI grant (2010-07). ; Gomis Vicens, J.; Carlos, L.; Bianco Prevot, A.; Teixeira, ACSC.; Mora Carbonell, M.; Amat Payá, AM.; Vicente Candela, R. (2015). Bio-based substances from urban waste as auxiliaries for solar photo-Fenton treatment under mild conditions: Optimization of operational variables. Catalysis Today. 240(Part A):39-45. https://doi.org/10.1016/j.cattod.2014.03.034 ; S ; 39 ; 45 ; 240 ; Part A

12664 12672 24 14 ; S ; The final publication is available at Springer via http://dx.doi.org/10.1007/s11356-016-7889-1 In this paper, the possibility of reusing textile effluents for new dyeing baths has been investigated. For this purpose, different trichromies using Direct Red 80, Direct Blue 106, and Direct Yellow 98 on cotton have been used. Effluents have been treated by means of a photo-Fenton process at pH 5. Addition of humic-like substances isolated form urban wastes is necessary in order to prevent iron deactivation because of the formation of non-active iron hydroxides. Laboratory-scale experiments carried out with synthetic effluents show that comparable results were obtained when using as solvent water treated by photo-Fenton with SBO and fresh deionized water. Experiments were scaled up to pilot plant illuminated under sunlight, using in this case a real textile effluent. Decoloration of the effluent could be achieved after moderate irradiation and cotton dyed with this water presented similar characteristics as when deionized water was used. This work was realized with the financial support of a Marie Sklodowska-Curie Research and Innovation Staff Exchange project funded by the European Commission H2020-MSCA-RISE-2014 within the framework of the research project Mat4treaT (project number 645551). Financial support from Spanish Government (CTQ2015-69832-C4-4-R) is gratefully acknowledged. The authors acknowledge the financial support of the Generalitat Valenciana, Conselleria d'Educació, Cultura i Esport (GV/AICO/2015/124) and CTQ2015-69832-C4-4-R. García-Negueroles, P.; Bou-Belda, E.; Santos-Juanes Jordá, L.; Amat Payá, AM.; Arques Sanz, A.; Vercher Pérez, RF.; Monllor Pérez, P. (2017). Treatment and reuse of textile wastewaters by mild solar photo-Fenton in the presence of humic-like substances. Environmental Science and Pollution Research. 24(14):12664-12672. https://doi.org/10.1007/s11356-016-7889-1 Ali N, Hameed A et al (2009) Physicochemical characterization and bioremediation perspective of ...

The final publication is available at Springer via http://dx.doi.org/10.1007/s11356-016-7889-1 ; In this paper, the possibility of reusing textile effluents for new dyeing baths has been investigated. For this purpose, different trichromies using Direct Red 80, Direct Blue 106, and Direct Yellow 98 on cotton have been used. Effluents have been treated by means of a photo-Fenton process at pH 5. Addition of humic-like substances isolated form urban wastes is necessary in order to prevent iron deactivation because of the formation of non-active iron hydroxides. Laboratory-scale experiments carried out with synthetic effluents show that comparable results were obtained when using as solvent water treated by photo-Fenton with SBO and fresh deionized water. Experiments were scaled up to pilot plant illuminated under sunlight, using in this case a real textile effluent. Decoloration of the effluent could be achieved after moderate irradiation and cotton dyed with this water presented similar characteristics as when deionized water was used. ; This work was realized with the financial support of a Marie Sklodowska-Curie Research and Innovation Staff Exchange project funded by the European Commission H2020-MSCA-RISE-2014 within the framework of the research project Mat4treaT (project number 645551). Financial support from Spanish Government (CTQ2015-69832-C4-4-R) is gratefully acknowledged. The authors acknowledge the financial support of the Generalitat Valenciana, Conselleria d'Educació, Cultura i Esport (GV/AICO/2015/124) and CTQ2015-69832-C4-4-R. ; García-Negueroles, P.; Bou-Belda, E.; Santos-Juanes Jordá, L.; Amat Payá, AM.; Arques Sanz, A.; Vercher Pérez, RF.; Monllor Pérez, P. (2017). Treatment and reuse of textile wastewaters by mild solar photo-Fenton in the presence of humic-like substances. Environmental Science and Pollution Research. 24(14):12664-12672. https://doi.org/10.1007/s11356-016-7889-1 ; S ; 12664 ; 12672 ; 24 ; 14 ; Ali N, Hameed A et al (2009) Physicochemical characterization and bioremediation ...