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Sixto Malato - One of the best experts on this subject based on the ideXlab platform.
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photo fenton treatment of saccharin in a solar pilot Compound Parabolic Collector use of olive mill wastewater as iron chelating agent preliminary results
Journal of Hazardous Materials, 2019Co-Authors: Konstantina Davididou, Efthalia Chatzisymeon, Leonidas Perezestrada, Izabell Oller, Sixto MalatoAbstract:Abstract The aim of this work was to investigate the treatment of the artificial sweetener saccharin (SAC) in a solar Compound Parabolic Collector pilot plant by means of the photo-Fenton process at pH 2.8. Olive mill wastewater (OMW) was used as iron chelating agent to avoid acidification of water at pH 2.8. For comparative purposes, Ethylenediamine-N, N-disuccinic acid (EDDS), a well-studied iron chelator, was also employed at circumneutral pH. Degradation products formed along treatment were identified by LC-QTOF-MS analysis. Their degradation was associated with toxicity removal, evaluated by monitoring changes in the bioluminescence of Vibrio fischeri bacteria. Results showed that conventional photo-Fenton at pH 2.8 could easily degrade SAC and its intermediates yielding k, apparent reaction rate constant, in the range of 0.64–0.82 L kJ−1, as well as, eliminate effluent’s chronic toxicity. Both OMW and EDDS formed iron-complexes able to catalyse H2O2 decomposition and generate HO . OMW yielded lower SAC oxidation rates (k = 0.05–0.1 L kJ−1) than EDDS (k = 2.21–7.88 L kJ−1) possibly due to its higher TOC contribution. However, the degradation rates were improved (k = 0.13 L kJ−1) by increasing OMW dilution in the reactant mixture. All in all, encouraging results were obtained by using OMW as iron chelating agent, thus rendering this approach promising towards the increase of process sustainability.
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microcontaminant degradation in municipal wastewater treatment plant secondary effluent by edds assisted photo fenton at near neutral ph an experimental design approach
Catalysis Today, 2015Co-Authors: Cesar Pulgarin, S Papoutsakis, S Mirallescuevas, I Oller, J Garcia L Sanchez, Sixto MalatoAbstract:This work aims to evaluate the applicability of EDDS (ethylenediamine-N,N'-disuccinic acid) as an iron chelating agent for photo-Fenton treatment of municipal wastewater spiked with organic contaminants at near-neutral pH. A series of laboratory scale experiments are conducted under simulated sunlight in accordance with a central composite experimental design in order to define the most favorable conditions in terms of initial iron concentration (maintaining a molar ratio 1:2 of Fe:EDDS), H2O2 and pH. The system is evaluated in terms of degradation efficiency, H2O2 consumption and iron availability. The simulated system has been compared in terms of degradation efficiency with a 60 L Compound Parabolic Collector (CPC), and significant correlation has been observed. An approach for estimating near-optimal regions of operability is also demonstrated. (C) 2015 Elsevier B.V. All rights reserved.
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Treatment of Municipal Wastewater Treatment Plant Effluents with Modified Photo-Fenton As a Tertiary Treatment for the Degradation of Micro Pollutants and Disinfection
Environmental Science & Technology, 2012Co-Authors: Nikolaus Klamerth, Ana Agüera, Sixto Malato, Amadeo R. Fernández-alba, Gilles MailhotAbstract:The goal of this paper was to develop a modified photo-Fenton treatment able to degrade micro pollutants in municipal wastewater treatment plant (MWTP) effluents at a neutral pH with minimal iron and H2O2 concentrations. Complexation of Fe by ethylenediamine-N,N′-disuccinic acid (EDDS) leads to stabilization and solubilization of Fe at natural pH. Photo-Fenton experiments were performed in a pilot Compound Parabolic Collector (CPC) solar plant. Samples were treated with solid phase extraction (SPE) and analyzed by HPLC-Qtrap-MS. The rapid degradation of contaminants within the first minutes of illumination and the low detrimental impact on degradation of bicarbonates present in the water suggested that radical species other than HO• are responsible for the efficiency of such photo-Fenton process. Disinfection of MWTP effluents by the same process showed promising results, although disinfection was not complete.
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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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Effects of experimental conditions on E. coli survival during solar photocatalytic water disinfection
Journal of Photochemistry and Photobiology A-chemistry, 2007Co-Authors: C. Sichel, Sixto Malato, Julián Blanco, Pilar Fernández-ibáñezAbstract:Abstract Results of photocatalytic disinfection of Escherichia coli K12 in water in a Compound Parabolic Collector (CPC) solar reactor are reported. The aim of the study is to quantify the influence of operating parameters, such as flow rate, water quality and bacterial concentration, on bacterial viability in solar photocatalysis and in the dark. The catalyst used was an industrial titanium-dioxide-coated paper matrix fixed on a tubular support in the focus of the CPC. Addition of TiO2 notably improved solar-only disinfection up to 6 logs disinfection in 90 min. Between 10 and 2 L/min, photocatalytic disinfection effectiveness tended to increase with decreasing flow rates. In dark experiments, inactivation of 99% of viable E. coli cells in distilled water was detected after 90 min of recirculation at 10 L/min in the CPC reactor. A detailed study of bacterial viability in the solar reactor in the dark was therefore performed, varying flow rates, initial concentrations and osmolarity. It was found that bacterial viability in the reactor strongly depends on all the parameters examined, so that disinfection and dark inactivation overlap when working under low-osmolarity conditions and low bacterial concentrations.
Cesar Pulgarin - One of the best experts on this subject based on the ideXlab platform.
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microcontaminant degradation in municipal wastewater treatment plant secondary effluent by edds assisted photo fenton at near neutral ph an experimental design approach
Catalysis Today, 2015Co-Authors: Cesar Pulgarin, S Papoutsakis, S Mirallescuevas, I Oller, J Garcia L Sanchez, Sixto MalatoAbstract:This work aims to evaluate the applicability of EDDS (ethylenediamine-N,N'-disuccinic acid) as an iron chelating agent for photo-Fenton treatment of municipal wastewater spiked with organic contaminants at near-neutral pH. A series of laboratory scale experiments are conducted under simulated sunlight in accordance with a central composite experimental design in order to define the most favorable conditions in terms of initial iron concentration (maintaining a molar ratio 1:2 of Fe:EDDS), H2O2 and pH. The system is evaluated in terms of degradation efficiency, H2O2 consumption and iron availability. The simulated system has been compared in terms of degradation efficiency with a 60 L Compound Parabolic Collector (CPC), and significant correlation has been observed. An approach for estimating near-optimal regions of operability is also demonstrated. (C) 2015 Elsevier B.V. All rights reserved.
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solar light hv and h2o2 hv photo disinfection of natural alkaline water ph 8 6 in a Compound Parabolic Collector at different day periods in sahelian region
Environmental Science and Pollution Research, 2015Co-Authors: Juliette Ndounla, Cesar PulgarinAbstract:The photo-disinfection of natural alkaline surface water (pH 8.6 +/- 0.3) for drinking purposes was carried out under solar radiation treatments. The enteric bacteria studied were the wild total coliforms/Escherichia coli (10(4) CFU/ml) and Salmonella spp. (10(4) CFU/ml) naturally present in the water. The photo-disinfection of a 25-l water sample was carried out in a solar Compound Parabolic Collector (CPC) in the absence and in the presence of hydrogen peroxide (H2O2). The addition of H2O2 (10 mg/L) to the sample water was sufficient to enhance the photo-disinfection and ensure an irreversible lethal action on the wild enteric bacteria contents of the sample. The inactivation kinetic of the system was significantly enhanced compared to the one carried out without H2O2 addition. The effect of the solar radiation parameters on the efficiency of the photo-disinfection were assessed. The pH has increased during the treatment in all the photo-disinfection processes (hv and H2O2/hv). The Salmonella spp strain has shown the best effective inactivate time in alkaline water than the one recorded under acidic or near-neutral conditions. The evolution of some physico-chemical parameters of the water (turbidity, NO2 (-), NO3 (-), NH4 (+), HPO4 (2-), and bicarbonate (HCO3 (-))) was monitored during the treatment. Finally, the possible mechanistic process involved during the enteric bacteria inactivation was suggested.
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shift from heterogeneous to homogeneous catalysis during resorcinol degradation using the solar photo fenton process initiated at circumneutral ph
Applied Catalysis B-environmental, 2015Co-Authors: Jose Fernando Barona, Diego Fernando Morales, Luis Ferney Gonzalezbahamon, Cesar Pulgarin, Luis Norberto BenitezAbstract:The photo-Fenton process (Fe-2+,Fe-3+/H2O2/hv) is known to degrade aqueous organic Compounds at acidic pHs. Nevertheless, recent studies have shown that this process also occurs at circumneutral pHs. Dihydroxybenzene isomers (i.e., resorcinol, hydroquinone and catechol) were selected as models of degradation by-products of natural organic matter and were degraded in water via the solar photoFenton process in a Compound Parabolic Collector (CPC). The experiments were carried out at neutral pH and with 0.7 and 40.0 mg L-1 of iron and H2O2, respectively. Despite sharing a similar chemical structure as the other two isomers, resorcinol was more recalcitrant to degradation under these conditions. Thus, we conducted a detailed study of this Compound's transformation through the photo-Fenton process. The effects of initial pH (5.0, 6.0 and 7.4) on resorcinol degradation were investigated, and in all experiments, pH, total organic carbon (TOC), resorcinol, dissolved iron forms and H2O2 were monitored. The results led us to consider that a photo-Fenton system at circumneutral pH follows a different mechanism than the pathway that is generally accepted for acidic pH values. A photo-Fenton process initiated at neutral pH is mainly heterogeneous; however, as the pH progressively decreases due to the generation of acidic by-products, the process becomes more homogeneous, and the degradation rate increases concomitantly. The pH also dramatically drops to approximately 5.7. A mechanism is proposed to explain the key shift from heterogeneous towards homogeneous photo-Fenton degradation processes. (C) 2014 Elsevier B.V. All rights reserved.
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Evaluation of the efficiency of the photo Fenton disinfection of natural drinking water source during the rainy season in the Sahelian region
Science of The Total Environment, 2014Co-Authors: Juliette Ndounla, Cesar PulgarinAbstract:The photo-disinfection of water from two different wells (W1, pH: 4.6–5.1 ± 0.02) and (W2 pH: 5.6–5.7 ± 0.02) was carried out during the rainy season at Ouagadougou–Burkina Faso, West Africa. The weather variation during the rainy season significantly affects the photo-disinfection processes (solar disinfection and photo-Fenton). The dilution of the water by rainwater highly affected the chemical composition of the wells' water used in this study; very low iron contents Compared to the ones recorded during the dry season were recorded in all water samples. Both photo-disinfection processes were used to treat 25 L of water in a Compound Parabolic Collector (CPC). None of them have shown the total inactivation of both wild enteric bacteria strains (total coliforms/E. coli and Salmonella spp.) involved in the treatment. However, the total coliforms/E. coli strains were totally inactivated during the exposure under most of the photo-Fenton treatment. Also, the remaining strains, especially those of Salmonella spp. were achieved during the subsequent 24 h of dark storage under the action of the Fenton process. Under uniquely solar radiation, total inactivation was recorded only in the total coliforms/E. coli strains. The impact of the available irradiance on the efficiency of the photo-Fenton disinfection of natural water was highlighted during the exposure under high intermittent solar radiation. The impact of the HCO3− concentration of both wells' water on the evolution of the pH during the photo-disinfection was recorded. Drastic decrease was noticed after the initial fast increase in presence of low HCO3− concentration while a steady state was observed after the increase in presence of higher concentration. The redox activities of the nitrogen components of the water during both photo-disinfection processes have led to increased concentration of nitrite in all the cases and variations were noticed in that of nitrate and ammonia.
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iron catalyzed low cost solar activated process for drinking water disinfection in colombian rural areas
Technologies for Sustainable Development, 2014Co-Authors: Cristina Rualeslonfat, Jose Fernando Barona, Alejandro Moncayolasso, Angelica Varon Lopez, Norberto Benitez Vasquez, Cesar PulgarinAbstract:Solar Water Disinfection (SODIS) is enhanced by the addition of small amounts of \( {\text{H}}_{2} {\text{O}}_{2} \)/iron salts under solar irradiation. The disinfecting efficiency of the photo-assisted systems: \( {\text{Fe}}^{2 + /3 + } /{\text{h}}\upnu \) and \( {\text{Fe}}^{2 + } /{\text{H}}_{2} {\text{O}}_{2} /{\text{h}}\upnu \) were observed at laboratory scale. At field scale using a 20-L Compound Parabolic Collector (CPC) reactor to treat river water (Pance River, in Cali, Colombia), the total bacterial inactivation was attained within 49 kJ/L of accumulated energy. Borosilicate and polyethylene terephthalate (PET) bottles used for Escherichia coli (E. coli) inactivation under simulated solar light showed similar inactivation kinetics leading to 8-log10 reduction of the E. coli concentration within 4 h. In presence of \( {\text{Fe}}^{2 + } /{\text{H}}_{2} {\text{O}}_{2} /{\text{h}}\upnu \), a dramatic enhancement of bacterial inactivation rate was observed leading to 9-log10 bacterial reduction within 2 h for PET and borosilicate bottles. PET bottles were also evaluated under natural sunlight and complete E. coli inactivation was reached at pH 6.3 with 50 kJ/L of accumulated energy. After the photocatalytic treatment, no bacterial re-growth was observed within the next 24 h of dark storage. These results exhibit the potential of the near-neutral photo-Fenton process for enhancing SODIS. Furthermore, PET bottles appear to be a promising option for application at the household-level for the rural population of developing countries, receiving a relatively high daylight sun irradiation.
S Malato - One of the best experts on this subject based on the ideXlab platform.
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assessment of solar photocatalysis using ag bivo4 at pilot solar Compound Parabolic Collector for inactivation of pathogens in well water and secondary effluents
Catalysis Today, 2017Co-Authors: Amin Yoosefi Booshehri, S Malato, Maria Inmaculada Pololopez, Maria Castroalferez, Wang Rong, Pilar FernandezibanezAbstract:Abstract Advanced oxidation processes (AOPs), such as photocatalysis driven by natural sunlight have been demonstrated to be a promising technology for degradation of hazardous chemical Compounds and inactivation of microorganisms in water. Among already exiting photocatalysts, for solar water treatment, currently visible light-active photocatalysts such as bismuth vanadate (BiVO 4 ), have received much attention from researchers. This work reports on the capacity of new synthetized Ag modified BiVO 4 composite to inactivate E. coli, E. faecalis and spores of F. solani in different water matrices. Proof of principle experiments performed at laboratory scale (200 mL of distilled water in stirred tank reactor) demonstrated the capability of this photocatalyst to inactivate those pathogens. A range of Ag loadings were investigated, demonstrating that 15% of Ag was the best option for water disinfection under natural sunlight. Although, TiO 2 -P25 is a better material for the solar photocatalytic disinfection of water under real sun. The cytotoxic effect of Ag/BiVO 4 composites was investigated by testing its cytotoxicity in human dermal fibroblasts (HDF). This result was supported also by the lack of bactericidal effect of the composites as it was demonstrated to not compromise the viability of E. coli , E. faecalis and F. solani spores in dark (1 g L −1 of Ag(15%)/BiVO 4 ) for 3 h in the case of E. coli and for 5 h for the others. Up-scaling the treatment to CPC flow-reactor of 10 L was successfully done in distilled water and well water; meanwhile inactivation of microorganism in secondary effluent (SE) from a Municipal Wastewater Treatment Plant was achieved only in the case of naturally occurring E. coli . Several concentrations of catalyst were investigated, and best inactivation efficiency was found to be 1 g L −1 for all microorganisms, solar reactors and water matrices. The influence of chemical composition of the water matrix was also investigated. The presence of high concentrations of carbonates/bicarbonates (in well water) did not affect significantly the photocatalytic efficiency; while natural organic matter (in SE) strongly limited the process probably due to the competitiveness for the radicals generated.
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light induced catalytic transformation of ofloxacin by solar fenton in various water matrices at a pilot plant mineralization and characterization of major intermediate products
Science of The Total Environment, 2013Co-Authors: I Michael, S Malato, Evroula Hapeshi, Jaume Acena, Sandra Perez, Mira Petrovic, A Zapata, Damia Barcelo, Despo FattakassinosAbstract:This work investigated the application of a solar driven advanced oxidation process (solar Fenton), for the degradation of the antibiotic ofloxacin (OFX) in various environmental matrices at a pilot-scale. All experiments were carried out in a Compound Parabolic Collector pilot plant in the presence of doses of H2O2 (2.5 mg L(-1)) and at an initial Fe(2+) concentration of 2 mg L(-1). The water matrices used for the solar Fenton experiments were: demineralized water (DW), simulated natural freshwater (SW), simulated effluent from municipal wastewater treatment plant (SWW) and pre-treated real effluent from municipal wastewater treatment plant (RE) to which OFX had been spiked at 10 mg L(-1). Dissolved organic carbon removal was found to be dependent on the chemical composition of the water matrix. OFX mineralization was higher in DW (78.1%) than in SW (58.3%) at 12 mg L(-1) of H2O2 consumption, implying the complexation of iron or the scavenging of hydroxyl radicals by the inorganic ions present in SW. On the other hand, the presence of dissolved organic matter (DOM) in SWW and RE, led to lower mineralization per dose of H2O2 compared to DW and SW. The major transformation products (TPs) formed during the solar Fenton treatment of OFX, were elucidated using liquid chromatography-time of flight-mass spectrometry (LC-ToF-MS). The transformation of OFX proceeded through a defluorination reaction, accompanied by some degree of piperazine and quinolone substituent transformation while a hydroxylation mechanism occurred by attack of the hydroxyl radicals generated during the process leading to the formation of TPs in all the water matrices, seven of which were tentatively identified. The results obtained from the toxicity bioassays indicated that the toxicity originates from the DOM present in RE and its oxidation products formed during the photocatalytic treatment and not from the TPs resulted from the oxidation of OFX.
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photocatalytic degradation of emerging contaminants in municipal wastewater treatment plant effluents using immobilized tio2 in a solar pilot plant
Applied Catalysis B-environmental, 2011Co-Authors: N Mirandagarcia, S Malato, S Suarez, B Sanchez, Juan M Coronado, Ignacio M MaldonadoAbstract:Abstract This article reports on degradation using TiO2 immobilized on glass spheres of 15 emerging contaminants (ECs) at low concentrations in simulated and real Municipal Wastewater Treatment Plant (MWTP) effluents. A sol containing titanium isopropoxide, commercial P25 and polyethylene glycol (PEG) was prepared, and a layer of the photoactive precursor was immobilized on glass spheres by dip-coating. The raw materials and the xerogels were characterized by N2 adsorption/desorption, XRD and TGA-DTA. The xerogel showed the TiO2 anatase, rutile and brookite crystal phases characteristic of the reference materials. The diffraction pattern showed no modification of the crystal size from incorporation of the PEG. Two different TiO2 anatase crystal sizes were identified, which was attributed to the different TiO2 precursors used in the synthesis route. Degradation of the emerging contaminants (acetaminophen, antipyrine, atrazine, carbamazepine, diclofenac, flumequine, hydroxybiphenyl, ibuprofen, isoproturon, ketorolac, ofloxacin, progesterone, sulfamethoxazole and triclosan), at an initial concentration of 100 μg L−1 each was determined by ultra-performance liquid chromatography (UPLC-UV) and mineralization was monitored by measuring the dissolved organic carbon (DOC). The experiments were performed in a pilot Compound Parabolic Collector (CPC) solar plant at the Plataforma Solar of Almeria (Spain). 85% of the Compounds were degraded within 120 min of illumination time depending on the water. The results show the potential application of this technology as a good alternative to suspension systems for the treatment of polluted water.
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coupled solar photo fenton and biological treatment for the degradation of diuron and linuron herbicides at pilot scale
Chemosphere, 2008Co-Authors: Maria Jose Farre, Wolfgang Gernjak, Isabel Oller, Manuel I Maldonado, S Malato, Xavier Domenech, Jose PeralAbstract:A coupled solar photo-Fenton (chemical) and biological treatment has been used to remove biorecalcitrant diuron (42 mg 1(-1)) and linuron (75 mg 1(-1)) herbicides from water at pilot plant scale. The chemical process has been carried out in a 82 1 solar pilot plant made up by four Compound Parabolic Collector units, and it was followed by a biological treatment performed in a 40 1 sequencing batch reactor. Two Fe(H) doses (2 and 5 mg 1(-1)) and sequential additions of H2O2 (20 mg 1(-1)) have been used to chemically degrade the initially polluted effluent. Next, biodegradability at different oxidation states has been assessed by means of BOD/COD ratio. A reagent dose of Fe = 5 mg 1(-1) and H2O2 = 100 mg 1(-1) has been required to obtain a biodegradable effluent after 100 min of irradiation time. Finally, the organic content of the photo-treated solution has been completely assimilated by a biomass consortium in the sequencing batch reactor using a total suspended solids concentration of 0.2 g 1(-1) and a hydraulic retention time of 24 h. Comparison between the data obtained at pilot plant scale (specially the one corresponding to the chemical step) and previously published data from a similar system performing at laboratory scale, has been carried out. (C) 2008 Elsevier Ltd. All rights reserved.
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advanced oxidation process biological system for wastewater containing a recalcitrant pollutant
Water Science and Technology, 2007Co-Authors: I Oller, Wolfgang Gernjak, S Malato, J A Sanchezperez, M I Maldonado, Leonidas PerezestradaAbstract:Two advanced oxidation processes (AOPs), ozonation and photo-Fenton, combined with a pilot aerobic biological reactor at field scale were employed for the treatment of industrial non-biodegradable saline wastewater (TOC around 200 mg L-1) containing a biorecalcitrant Compound, a-methylphenylglycine (MPG), at a concentration of 500 mg L-1. Ozonation experiments were performed in a 50-L reactor with constant inlet ozone of 21.9 g m-3. Solar photo-Fenton tests were carried out in a 75-L pilot plant made up of four Compound Parabolic Collector (CPC) units. The catalyst concentration employed in this system was 20 mg L-1 of Fe2 + and the H2O2 concentration was kept in the range of 200–500 mg L-1. Complete degradation of MPG was attained after 1,020 min of ozone treatment, while only 195 min were required for photo-Fenton. Samples from different stages of both AOPs were taken for Zahn–Wellens biocompatibility tests. Biodegradability enhancement of the industrial saline wastewater was confirmed (>70% biodegradability). Biodegradable Compounds generated during the preliminary oxidative processes were biologically mineralised in a 170-L aerobic immobilised biomass reactor (IBR). The global efficiency of both AOP/biological combined systems was 90% removal of an initial TOC of over 500 mg L-1
J M Monteagudo - One of the best experts on this subject based on the ideXlab platform.
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solar photo fenton treatment of wastewater from the beverage industry intensification with ferrioxalate
Chemical Engineering Journal, 2015Co-Authors: Ayha Dura, J M Monteagudo, J Gil, A.j. Expósito, Sa I MartiAbstract:Abstract The mineralization of industrial wastewater from beverage industries during a solar photo-Fenton enhanced process mediated by ferrioxalate complexes was evaluated as an alternative to reduce the total treatment time required for conventional anaerobic digestion procedures in a Compound Parabolic Collector (CPC) pilot plant. Under selected conditions (H 2 O 2 flowrate = 460 mL/h, H 2 C 2 O 4 flowrate = 2100 mL/h, [Fe] 0 = 150 mg/L, pH = 2.79, medium solar power = 35.8 Wh) and continuous operation, 70.6% and 96.6% of the total organic carbon (TOC) was removed from industrial effluent with an initial TOC concentration of 1386.8 mg/L after 55 and 125 min, respectively. In addition, this process completely removed the toxicity and COD and removed 99.8% of the BOD-5. First, the physico-chemical pre-treatment of raw wastewater was performed based on sedimentation to remove suspended solids and reduce the turbidity by 91%. The effects of the variables were studied during two different irradiation periods. Solar power is the main factor that influences mineralization during the first 60 Wh of accumulated energy due to the generation of hydroxyl radicals. However, solar power is unimportant at the end of the process (150 Wh of accumulated energy), when the molecular reaction mechanism between H 2 O 2 and the intermediates is predominant. The overall mineralization process ( k = 0.0096 min −1 ) occurs due to the contributions of the photo-Fenton process ( k = 0.0044 min −1 ) and the ferrioxalate photochemistry ( k = 0.003 min −1 ). The synergism between both processes was 22.9% based on the first order rate constants for TOC removal.
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photocatalytic treatment of an industrial effluent using artificial and solar uv radiation an operational cost study on a pilot plant scale
Journal of Environmental Management, 2012Co-Authors: A. Duran, J M Monteagudo, San I MartinAbstract:Abstract The aim of this work was to study the operation costs of treating a real effluent from an integrated gasification combined cycle (IGCC) power station located in Spain. The study compares different homogeneous photocatalytic processes on a pilot plant scale using different types of radiation (artificial UV or solar UV with a Compound Parabolic Collector). The efficiency of the processes was evaluated by an analysis of the total organic carbon (TOC) removed. The following processes were considered in the study: (i) a photo-Fenton process at an artificial UV pilot plant (with the initial addition of H 2 O 2 ), (ii) a modified photo-Fenton process with continuous addition of H 2 O 2 and O 2 to the system and (iii) a ferrioxalate-assisted solar photo-Fenton process at a Compound Parabolic Collector (CPC) pilot plant. The efficiency of these processes in degrading pollutants has been studied previously, and the results obtained in each of those studies have been published elsewhere. The operational costs due to the consumption of electrical energy, reagents and catalysts were calculated from the optimal conditions of each process. The results showed that the solar photo-Fenton system was economically feasible, being able to achieve up to 75% mineralization with a total cost of 6 €/m 3 , which can be reduced to 3.6 €/m 3 by subtracting the electrical costs because the IGCC plant is self-sufficient in terms of energy.
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optimization of the mineralization of a mixture of phenolic pollutants under a ferrioxalate induced solar photo fenton process
Journal of Hazardous Materials, 2011Co-Authors: J M Monteagudo, A. Duran, M Aguirre, San I MartinAbstract:Abstract The mineralization of solutions containing a mixture of three phenolic Compounds, gallic, p-coumaric and protocatechuic acids, in a ferrioxalate-induced solar photo-Fenton process was investigated. The reactions were carried out in a pilot plant consisting of a Compound Parabolic Collector (CPC) solar reactor. An optimization study was performed combining a multivariate experimental design and neuronal networks that included the following variables: pH, temperature, solar power, air flow and initial concentrations of H 2 O 2 , Fe(II) and oxalic acid. Under optimal conditions, total elimination of the original Compounds and 94% TOC removal of the mixture were achieved in 5 and 194 min, respectively. pH and initial concentrations of H 2 O 2 and Fe(II) were the most significant factors affecting the mixture mineralization. The molar correlation between consumed hydrogen peroxide and removed TOC was always between 1 and 3. A detailed analysis of the reaction was presented. The values of the pseudo-first-order mineralization kinetic rate constant, k TOC , increased as initial Fe(II) and H 2 O 2 concentrations and temperature increased. The optimum pH value also slightly increased with greater Fe(II) and hydrogen peroxide concentrations but decreased when temperature increased. OH and O 2 − radicals were the main oxidative intermediate species in the process, although singlet oxygen ( 1 O 2 ) also played a role in the mineralization reaction.
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effect of light source on the catalytic degradation of protocatechuic acid in a ferrioxalate assisted photo fenton process
Applied Catalysis B-environmental, 2010Co-Authors: J M Monteagudo, San I Martin, A. Duran, M AguirreAbstract:Abstract The catalytic degradation of protocatechuic acid (PA) solutions in a ferrioxalate-assisted photo-Fenton process irradiated with solar or artificial ultraviolet light sources was investigated. The reactions were carried out either in a pilot plant consisting of a Compound Parabolic Collector (CPC)-solar reactor or in a UV-A/C-lamp reactor. An optimization study was performed using a multivariate experimental design including the following variables: pH, temperature, solar power, air flow and initial concentrations of H2O2, Fe(II) and oxalic acid. The photocatalytic degradation efficiency was determined by measuring the elimination of the original PA and the removal of total organic carbon (TOC). TOC-removal rates of 97% and 96% were achieved under artificial UV-A/C and solar light, respectively, but with different optimum operating conditions. When artificial UV light was used in the presence of oxalic acid, the degradation rate was higher in the UV-C system than in the UV-A system because ferrioxalate complexes are primarily formed at 200–280 nm. OH radicals were the main oxidative intermediate species in the artificial UV-A/C process while superoxide and OH radicals played the most significant roles in the solar process. Artificial UV-A/C light can be used as an alternative to solar CPC on cloudy days.
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catalytic degradation of orange ii in a ferrioxalate assisted photo fenton process using a combined uv a c solar pilot plant system
Applied Catalysis B-environmental, 2010Co-Authors: J M Monteagudo, San I Martin, A. Duran, M AguirreAbstract:Abstract The catalytic degradation of Orange II in a ferrioxalate-assisted photo-Fenton process with combined solar and artificial ultraviolet light sources and continuous addition of H 2 O 2 was investigated. The reaction was carried out in a pilot plant consisting of a Compound Parabolic Collector (CPC) solar reactor in series with a UV-A/C reactor. An optimization study was done using a multivariate experimental design including the following variables: pH, H 2 O 2 flow rate, UV-lamp exposure time, average temperature, average solar power and initial concentrations of Fe(II) and oxalic acid. The photocatalytic degradation efficiency was determined by the analysis of color and total organic carbon (TOC) removal. Under the optimum conditions, TOC removal increased to 99% in only 45 min, and this system permitted the use of a low ferrous concentration of only 2 mg L −1 . In addition, oxalic acid was used for pH adjustment. Thus, the operating costs of Fe removal, chemicals and electric power were reduced. Artificial UV-A/C light can be used either to increase the efficiency of the single-solar process or as an alternative to solar CPC on cloudy days. The overall rate constant was split into three components: direct oxidation by hydrogen peroxide, photolytic breakdown of dye–oxalate complexes chromophore group and oxidation by hydroxyl radicals. The influence of the Fe catalyst on the molecular and/or radical reactions was studied by conducting the reaction in the presence and absence of tert-butyl alcohol; the radical mechanism's contribution to the overall degradation increased with increasing iron levels.
San I Martin - One of the best experts on this subject based on the ideXlab platform.
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photocatalytic treatment of an industrial effluent using artificial and solar uv radiation an operational cost study on a pilot plant scale
Journal of Environmental Management, 2012Co-Authors: A. Duran, J M Monteagudo, San I MartinAbstract:Abstract The aim of this work was to study the operation costs of treating a real effluent from an integrated gasification combined cycle (IGCC) power station located in Spain. The study compares different homogeneous photocatalytic processes on a pilot plant scale using different types of radiation (artificial UV or solar UV with a Compound Parabolic Collector). The efficiency of the processes was evaluated by an analysis of the total organic carbon (TOC) removed. The following processes were considered in the study: (i) a photo-Fenton process at an artificial UV pilot plant (with the initial addition of H 2 O 2 ), (ii) a modified photo-Fenton process with continuous addition of H 2 O 2 and O 2 to the system and (iii) a ferrioxalate-assisted solar photo-Fenton process at a Compound Parabolic Collector (CPC) pilot plant. The efficiency of these processes in degrading pollutants has been studied previously, and the results obtained in each of those studies have been published elsewhere. The operational costs due to the consumption of electrical energy, reagents and catalysts were calculated from the optimal conditions of each process. The results showed that the solar photo-Fenton system was economically feasible, being able to achieve up to 75% mineralization with a total cost of 6 €/m 3 , which can be reduced to 3.6 €/m 3 by subtracting the electrical costs because the IGCC plant is self-sufficient in terms of energy.
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optimization of the mineralization of a mixture of phenolic pollutants under a ferrioxalate induced solar photo fenton process
Journal of Hazardous Materials, 2011Co-Authors: J M Monteagudo, A. Duran, M Aguirre, San I MartinAbstract:Abstract The mineralization of solutions containing a mixture of three phenolic Compounds, gallic, p-coumaric and protocatechuic acids, in a ferrioxalate-induced solar photo-Fenton process was investigated. The reactions were carried out in a pilot plant consisting of a Compound Parabolic Collector (CPC) solar reactor. An optimization study was performed combining a multivariate experimental design and neuronal networks that included the following variables: pH, temperature, solar power, air flow and initial concentrations of H 2 O 2 , Fe(II) and oxalic acid. Under optimal conditions, total elimination of the original Compounds and 94% TOC removal of the mixture were achieved in 5 and 194 min, respectively. pH and initial concentrations of H 2 O 2 and Fe(II) were the most significant factors affecting the mixture mineralization. The molar correlation between consumed hydrogen peroxide and removed TOC was always between 1 and 3. A detailed analysis of the reaction was presented. The values of the pseudo-first-order mineralization kinetic rate constant, k TOC , increased as initial Fe(II) and H 2 O 2 concentrations and temperature increased. The optimum pH value also slightly increased with greater Fe(II) and hydrogen peroxide concentrations but decreased when temperature increased. OH and O 2 − radicals were the main oxidative intermediate species in the process, although singlet oxygen ( 1 O 2 ) also played a role in the mineralization reaction.
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effect of light source on the catalytic degradation of protocatechuic acid in a ferrioxalate assisted photo fenton process
Applied Catalysis B-environmental, 2010Co-Authors: J M Monteagudo, San I Martin, A. Duran, M AguirreAbstract:Abstract The catalytic degradation of protocatechuic acid (PA) solutions in a ferrioxalate-assisted photo-Fenton process irradiated with solar or artificial ultraviolet light sources was investigated. The reactions were carried out either in a pilot plant consisting of a Compound Parabolic Collector (CPC)-solar reactor or in a UV-A/C-lamp reactor. An optimization study was performed using a multivariate experimental design including the following variables: pH, temperature, solar power, air flow and initial concentrations of H2O2, Fe(II) and oxalic acid. The photocatalytic degradation efficiency was determined by measuring the elimination of the original PA and the removal of total organic carbon (TOC). TOC-removal rates of 97% and 96% were achieved under artificial UV-A/C and solar light, respectively, but with different optimum operating conditions. When artificial UV light was used in the presence of oxalic acid, the degradation rate was higher in the UV-C system than in the UV-A system because ferrioxalate complexes are primarily formed at 200–280 nm. OH radicals were the main oxidative intermediate species in the artificial UV-A/C process while superoxide and OH radicals played the most significant roles in the solar process. Artificial UV-A/C light can be used as an alternative to solar CPC on cloudy days.
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catalytic degradation of orange ii in a ferrioxalate assisted photo fenton process using a combined uv a c solar pilot plant system
Applied Catalysis B-environmental, 2010Co-Authors: J M Monteagudo, San I Martin, A. Duran, M AguirreAbstract:Abstract The catalytic degradation of Orange II in a ferrioxalate-assisted photo-Fenton process with combined solar and artificial ultraviolet light sources and continuous addition of H 2 O 2 was investigated. The reaction was carried out in a pilot plant consisting of a Compound Parabolic Collector (CPC) solar reactor in series with a UV-A/C reactor. An optimization study was done using a multivariate experimental design including the following variables: pH, H 2 O 2 flow rate, UV-lamp exposure time, average temperature, average solar power and initial concentrations of Fe(II) and oxalic acid. The photocatalytic degradation efficiency was determined by the analysis of color and total organic carbon (TOC) removal. Under the optimum conditions, TOC removal increased to 99% in only 45 min, and this system permitted the use of a low ferrous concentration of only 2 mg L −1 . In addition, oxalic acid was used for pH adjustment. Thus, the operating costs of Fe removal, chemicals and electric power were reduced. Artificial UV-A/C light can be used either to increase the efficiency of the single-solar process or as an alternative to solar CPC on cloudy days. The overall rate constant was split into three components: direct oxidation by hydrogen peroxide, photolytic breakdown of dye–oxalate complexes chromophore group and oxidation by hydroxyl radicals. The influence of the Fe catalyst on the molecular and/or radical reactions was studied by conducting the reaction in the presence and absence of tert-butyl alcohol; the radical mechanism's contribution to the overall degradation increased with increasing iron levels.