The Experts below are selected from a list of 1131 Experts worldwide ranked by ideXlab platform
Jorge Marcos Rosa - One of the best experts on this subject based on the ideXlab platform.
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dyeing of cotton with reactive dyestuffs the continuous reuse of textile wastewater effluent treated by ultraviolet hydrogen peroxide Homogeneous Photocatalysis
Journal of Cleaner Production, 2015Co-Authors: Jorge Marcos Rosa, Ana Maria Frattini Fileti, Elias Basile Tambourgi, Jose Carlos Curvelo SantanaAbstract:Abstract Ten differents dyeings were made using reuse water obtained from effluent after treatment by Homogeneous Photocatalysis. Before and after the UV/H2O2 treatments, the concentration of sodium chloride (NaCl), the absorbance (Abs) and the amount of total organic carbon (TOC) were monitored. All rates of decolorization were above 92% and the removal of TOC was above 88% in all treatments. Compared with the same dyeings made with deionized water, the total deviation (ΔE*) between the colors did not exceed 1.05. Currently, for a monthly production of 20 dyeings of 100 kg each, 160 m3 of water is consumed and an equal volume of effluent is generated. The same dyeings made by the process proposed in this study, with an addition of 10 m3 of water after 20 dyeings, would consume just 60 m3 of water, without effluent discharge containing high amounts of organic matter and high values of absorbance.
Sixto Malato - One of the best experts on this subject based on the ideXlab platform.
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photolytic and photocatalytic transformation of methadone in aqueous solutions under solar irradiation kinetics characterization of major intermediate products and toxicity evaluation
Water Research, 2011Co-Authors: Cristina Postigo, Manuel I Maldonado, Sixto Malato, I Oller, Carla Sirtori, Miren Lopez De Alda, Damia BarceloAbstract:The present manuscript describes the transformation and mineralization of methadone (MET) in aqueous solutions (demineralized water (DW) and synthetic municipal wastewater effluent (SWeff)) by natural solar irradiation and two solar photocatalytic processes: heterogeneous Photocatalysis with titanium dioxide (TiO2) and Homogeneous Photocatalysis by photo-Fenton. Direct solar irradiation resulted in almost complete transformation of MET in the investigated matrices after 20 h of normalized irradiation time. MET photocatalytic transformation required shorter illumination times in DW compared to SWeff. Only 16 and 36 min of solar illumination were required during photo-Fenton and Photocatalysis with TiO2, respectively, to transform MET completely in SWeff. Mineralization of the dissolved organic carbon took place only during photocatalytic treatments. Kinetics parameters were calculated for processes comparison. Additionally, phototransformation intermediates generated during each treatment were investigated and characterized by means of ultra-performance liquid chromatography coupled to quadrupole-time of flight tandem mass spectrometry (UPLC-QqTOF-MS/MS). The main MET phototransformation pathways were observed to be hydroxylation, and fragmentation and cyclization. According to the Vibrio fischeri bioassay, the acute toxicity of the generated phototransformation products was not relevant, since the observed inhibition percentages of bacterial bioluminescence were always below 30% after 30 min of sample contact.
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solar transformation and photocatalytic treatment of cocaine in water kinetics characterization of major intermediate products and toxicity evaluation
Applied Catalysis B-environmental, 2011Co-Authors: Cristina Postigo, Manuel I Maldonado, Sixto Malato, I Oller, Carla Sirtori, Miren Lopez De Alda, Damia BarceloAbstract:Abstract The present manuscript describes for the first time the transformation and mineralization of cocaine (COC) in water (distilled water (DW) and synthetic municipal wastewater effluent (SWeff)) by natural solar irradiation and two solar photocatalytic processes: heterogeneous Photocatalysis with titanium dioxide (TiO2) and Homogeneous Photocatalysis by photo-Fenton. The solar photocatalytic processes were run at equivalent pilot-plant scale by means of compound parabolic collectors, which allowed for comparison of solar transformation kinetics and compound mineralization. Direct photolysis resulted in almost complete and partial disappearance of COC in SWeff and DW, respectively, after 33 h of normalized irradiation time, and negligible mineralization. Solar transformation of COC by heterogeneous Photocatalysis with TiO2 was completed after 28 and 50 min of illumination in DW and SWeff, respectively, whereas about half of the irradiation time was needed with photo-Fenton, which was also proved to be more effective in compound mineralization. Kinetics parameters were calculated for process comparison. Additionally, the phototransformation intermediates generated during each treatment were investigated and characterized by means of ultra-performance liquid chromatography coupled to quadrupole-time of flight tandem mass spectrometry (UPLC-QqTOF-MS/MS). Identity confirmation was possible for some of them with the analysis of commercially available analytical standards. The main COC phototransformation pathways were observed to be ester bond cleavage, hydroxylation, and demethylation. Finally, the application of an acute toxicity test (Vibrio fischeri) to selected water samples resulted in inhibition percentages of bacterial bioluminescence in most cases below 20% after 30 min of sample contact, which indicates low acute toxicity of the photointermediates generated during the different treatments.
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solar photochemical treatment of winery wastewater in a cpc reactor
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Marco S. Lucas, Manuel I Maldonado, Sixto Malato, Rosa Mosteo, José A. PeresAbstract:Degradation of simulated winery wastewater was studied in a pilot-scale compound parabolic collector (CPC) solar reactor. Total organic carbon (TOC) reduction by heterogeneous Photocatalysis (TiO(2)) and Homogeneous Photocatalysis with photo-Fenton was observed. The influence of TiO(2) concentration (200 or 500 mg/L) and also of combining TiO(2) with H(2)O(2) or Na(2)S(2)O(8) on heterogeneous Photocatalysis was evaluated. Heterogeneous Photocatalysis with TiO(2), TiO(2)/H(2)O(2) and TiO(2)/S(2)O(8)(2-) is revealed to be inefficient in removing TOC, originating TOC degradation of 10%, 11% and 25%, respectively, at best. However, photo-Fenton experiments led to 46% TOC degradation in simulated wastewater prepared with diluted wine (WV) and 93% in wastewater prepared with diluted grape juice (WG), and if ethanol is previously eliminated from mixed wine and grape juice wastewater (WW) by air stripping, it removes 96% of TOC. Furthermore, toxicity decreases during the photo-Fenton reaction very significantly from 48% to 28%. At the same time, total polyphenols decrease 92%, improving wastewater biodegradability.
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solar heterogeneous and Homogeneous Photocatalysis as a pre treatment option for biotreatment
Research on Chemical Intermediates, 2007Co-Authors: I Oller, Manuel I Maldonado, Pilar Fernandezibanez, Leonidas Perezestrada, W Gernjak, Cesar Pulgarin, Paula Passarinho, Sixto MalatoAbstract:In this paper, we present pilot-scale solar Photo-Fenton and TiO2 treatment of a model compound (α-methylphenylglycine) dissolved in 500 mg/l concentration in water. Not only contaminant disappearance and mineralisation were evaluated, but also enhancement of biodegradability. The solar photoreactors, composed of 4.16 m2 of compound parabolic collectors, had a total volume of 82 l (44.6 l illuminated). Treatment was successful with both Advanced Oxidation Processes (AOPs) tested, but photo-Fenton was shown to be by far more efficient from the kinetic and practical point of view. To find out the conditions for biocompatibility using the AOPs as a pre-treatment, waste water after certain degradation time, unacclimated municipal sludge and mineral nutrients were placed together and evaluated by the Zahn-Wellens (Z-W) test. Biodegradability was enhanced (70% biodegradable) by both AOPs, but photo-Fenton was demonstrated to be more efficient, requiring a treatmen time one order of magnitude shorter than TiO2. Hydrogen peroxide management for reduced consumption and elimination prior to discharging water to the biotreatment step is also discussed in detail.
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applied studies in solar photocatalytic detoxification an overview
Solar Energy, 2003Co-Authors: Sixto Malato, J Caceres, J Blanco, Alfonso Vidal, D Alarcon, M I Maldonado, W GernjakAbstract:The technical feasibility and performance of photocatalytic degradation of four water-soluble pesticides (diuron, imidacloprid, formetanate and methomyl) have been studied at pilot scale in two well-defined systems which are of special interest because natural-solar UV light can be used for them: heterogeneous Photocatalysis with titanium dioxide and Homogeneous Photocatalysis by photo-Fenton. The pilot plant is made up of compound parabolic collectors specially designed for solar photocatalytic applications. The initial concentration tested with imidacloprid, formetanate and methomyl was 50 and 30 mg/l with diuron, and the catalyst concentrations were 200 mg/l and 0.05 mM with TiO2 and iron, respectively. Total disappearance of the parent compounds, 90% mineralisation and toxicity reduction below the threshold (EC50) have been attained with all pesticides tested. All these results have contributed to an evaluation of photocatalytic treatment capacity and comments on the main parameters of TiO2 and Fe separation from the treated water
Mehmet A Oturan - One of the best experts on this subject based on the ideXlab platform.
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removal of hydrophobic organic pollutants from soil washing flushing solutions a critical review
Journal of Hazardous Materials, 2016Co-Authors: Clement Trellu, Emmanuel Mousset, Yoan Pechaud, David Huguenot, Eric D Van Hullebusch, Giovanni Esposito, Mehmet A OturanAbstract:The release of hydrophobic organoxenobiotics such as polycyclic aromatic hydrocarbons, petroleum hydrocarbons or polychlorobiphenyls results in long-term contamination of soils and groundwaters. This constitutes a common concern as these compounds have high potential toxicological impact. Therefore, the development of cost-effective processes with high pollutant removal efficiency is a major challenge for researchers and soil remediation companies. Soil washing (SW) and soil flushing (SF) processes enhanced by the use of extracting agents (surfactants, biosurfactants, cyclodextrins etc.) are conceivable and efficient approaches. However, this generates high strength effluents containing large amount of extracting agent. For the treatment of these SW/SF solutions, the goal is to remove target pollutants and to recover extracting agents for further SW/SF steps. Heterogeneous Photocatalysis, technologies based on Fenton reaction chemistry (including Homogeneous Photocatalysis such as photo-Fenton), ozonation, electrochemical processes and biological treatments have been investigated. Main advantages and drawbacks as well as target pollutant removal mechanisms are reviewed and compared. Promising integrated treatments, particularly the use of a selective adsorption step of target pollutants and the combination of advanced oxidation processes with biological treatments, are also discussed.
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Removal of hydrophobic organic pollutants from soil washing/flushing solutions: A critical review.
Journal of Hazardous Materials, 2015Co-Authors: Clement Trellu, Emmanuel Mousset, Yoan Pechaud, David Huguenot, Eric D Van Hullebusch, Giovanni Esposito, Mehmet A OturanAbstract:The release of hydrophobic organoxenobiotics such as polycyclic aromatic hydrocarbons, petroleum hydrocarbons or polychlorobiphenyls results in long-term contamination of soils and groundwaters. This constitutes a common concern as these compounds have high potential toxicological impact. Therefore, the development of cost-effective processes with high pollutant removal efficiency is a major challenge for researchers and soil remediation companies. Soil washing (SW) and soil flushing (SF) processes enhanced by the use of extracting agents (surfactants, biosurfactants, cyclodextrins etc.) are conceivable and efficient approaches. However, this generates high strength effluents containing large amount of extracting agent. For the treatment of these SW/SF solutions, the goal is to remove target pollutants and to recover extracting agents for further SW/SF steps. Heterogeneous Photocatalysis, technologies based on Fenton reaction chemistry (including Homogeneous Photocatalysis such as photo-Fenton), ozonation, electrochemical processes and biological treatments have been investigated. Main advantages and drawbacks as well as target pollutant removal mechanisms are reviewed and compared. Promising integrated treatments, particularly the use of a selective adsorption step of target pollutants and the combination of advanced oxidation processes with biological treatments, are also discussed.
Damia Barcelo - One of the best experts on this subject based on the ideXlab platform.
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photolytic and photocatalytic transformation of methadone in aqueous solutions under solar irradiation kinetics characterization of major intermediate products and toxicity evaluation
Water Research, 2011Co-Authors: Cristina Postigo, Manuel I Maldonado, Sixto Malato, I Oller, Carla Sirtori, Miren Lopez De Alda, Damia BarceloAbstract:The present manuscript describes the transformation and mineralization of methadone (MET) in aqueous solutions (demineralized water (DW) and synthetic municipal wastewater effluent (SWeff)) by natural solar irradiation and two solar photocatalytic processes: heterogeneous Photocatalysis with titanium dioxide (TiO2) and Homogeneous Photocatalysis by photo-Fenton. Direct solar irradiation resulted in almost complete transformation of MET in the investigated matrices after 20 h of normalized irradiation time. MET photocatalytic transformation required shorter illumination times in DW compared to SWeff. Only 16 and 36 min of solar illumination were required during photo-Fenton and Photocatalysis with TiO2, respectively, to transform MET completely in SWeff. Mineralization of the dissolved organic carbon took place only during photocatalytic treatments. Kinetics parameters were calculated for processes comparison. Additionally, phototransformation intermediates generated during each treatment were investigated and characterized by means of ultra-performance liquid chromatography coupled to quadrupole-time of flight tandem mass spectrometry (UPLC-QqTOF-MS/MS). The main MET phototransformation pathways were observed to be hydroxylation, and fragmentation and cyclization. According to the Vibrio fischeri bioassay, the acute toxicity of the generated phototransformation products was not relevant, since the observed inhibition percentages of bacterial bioluminescence were always below 30% after 30 min of sample contact.
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solar transformation and photocatalytic treatment of cocaine in water kinetics characterization of major intermediate products and toxicity evaluation
Applied Catalysis B-environmental, 2011Co-Authors: Cristina Postigo, Manuel I Maldonado, Sixto Malato, I Oller, Carla Sirtori, Miren Lopez De Alda, Damia BarceloAbstract:Abstract The present manuscript describes for the first time the transformation and mineralization of cocaine (COC) in water (distilled water (DW) and synthetic municipal wastewater effluent (SWeff)) by natural solar irradiation and two solar photocatalytic processes: heterogeneous Photocatalysis with titanium dioxide (TiO2) and Homogeneous Photocatalysis by photo-Fenton. The solar photocatalytic processes were run at equivalent pilot-plant scale by means of compound parabolic collectors, which allowed for comparison of solar transformation kinetics and compound mineralization. Direct photolysis resulted in almost complete and partial disappearance of COC in SWeff and DW, respectively, after 33 h of normalized irradiation time, and negligible mineralization. Solar transformation of COC by heterogeneous Photocatalysis with TiO2 was completed after 28 and 50 min of illumination in DW and SWeff, respectively, whereas about half of the irradiation time was needed with photo-Fenton, which was also proved to be more effective in compound mineralization. Kinetics parameters were calculated for process comparison. Additionally, the phototransformation intermediates generated during each treatment were investigated and characterized by means of ultra-performance liquid chromatography coupled to quadrupole-time of flight tandem mass spectrometry (UPLC-QqTOF-MS/MS). Identity confirmation was possible for some of them with the analysis of commercially available analytical standards. The main COC phototransformation pathways were observed to be ester bond cleavage, hydroxylation, and demethylation. Finally, the application of an acute toxicity test (Vibrio fischeri) to selected water samples resulted in inhibition percentages of bacterial bioluminescence in most cases below 20% after 30 min of sample contact, which indicates low acute toxicity of the photointermediates generated during the different treatments.
Jose Carlos Curvelo Santana - One of the best experts on this subject based on the ideXlab platform.
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dyeing of cotton with reactive dyestuffs the continuous reuse of textile wastewater effluent treated by ultraviolet hydrogen peroxide Homogeneous Photocatalysis
Journal of Cleaner Production, 2015Co-Authors: Jorge Marcos Rosa, Ana Maria Frattini Fileti, Elias Basile Tambourgi, Jose Carlos Curvelo SantanaAbstract:Abstract Ten differents dyeings were made using reuse water obtained from effluent after treatment by Homogeneous Photocatalysis. Before and after the UV/H2O2 treatments, the concentration of sodium chloride (NaCl), the absorbance (Abs) and the amount of total organic carbon (TOC) were monitored. All rates of decolorization were above 92% and the removal of TOC was above 88% in all treatments. Compared with the same dyeings made with deionized water, the total deviation (ΔE*) between the colors did not exceed 1.05. Currently, for a monthly production of 20 dyeings of 100 kg each, 160 m3 of water is consumed and an equal volume of effluent is generated. The same dyeings made by the process proposed in this study, with an addition of 10 m3 of water after 20 dyeings, would consume just 60 m3 of water, without effluent discharge containing high amounts of organic matter and high values of absorbance.