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To prevent an environmental pollution by hazardous heavy metals, in the present study, a simulatenous decrease of the concentration of Pb((II) and Cu(II) in the solution by photo-Fenton method has been systematically studied. Photo-Fenton process proceeded in a close reactor by batch technique. The process was conducted by exposure solutions containing Pb(II) and Cu(II) ions, and Fenton’s reagent (Fe2+ and H2O2) under UV-A lamp. In this study, the initial concentations of Pb(II) and Cu(II), and the exposure time were optimized. The synergyc effect that may be appeared on the decrease of Pb(II) and Cu(II) ion concentrations simultaneously through photo-Fenton process was also addressed. The concentrations of Pb(II) and Cu(II) in the solution were determined by AAS. The research results exhibited that photo-Fenton process could decrease Pb(II) and Cu(II) concentrations, and the maximum decreases, 46.12 % dan 16.86% for Pb(II) and for Cu(II) respecticely, were found by applying both initial concentration of Pb(II) and Cu(II) as much 35 mg/L, and 60 min of the time. The concentration decreases of Pb (II) and Cu(II) were results of oxidation by OH and by electron to form PbO2 and Cu particles respectively as probed by EDX data. Furthermore, photo-Fenton process toward a solution containing Pb(II) and Cu(II) ions allowed oxidation of Pb(II) and reduction of Cu(II) simultaneously and showed a synergic effect. Such effect was demonstrated by the fact that the presence of Cu(II) ion in the photo-Fenton process of Pb(II) solution could improve the Pb(II) oxidation and the highest improvement of Pb(II) oxidation (81.06%) was shown by 35 mg/L of the Cu(II) concentration. Similarly, the presence of Pb(II) in the photo-Fenton process of Cu(II) solution could enhance the reduction of Cu(II), and the highest effect on the Cu(II) reduction enhancement was exhibited by 35 mg/L of the Pb(II) concentration.

The objective of this work was to evaluate the degradation of rhodamine B dye from aqueous solution by photo-Fenton reaction under visible irradiation using a Fe-rich bentonite as a catalyst. The material was thermally treated at a low temperature (200 °C) and characterized by XRD, N2 adsorption-desorption isotherms, FTIR, SEM-EDS and XRF. Iron leaching in aqueous solution after the photo-Fenton reaction was evaluated by atomic absorption spectroscopy. The material exhibited a mesoporous structure, containing a specific surface area of 99 m2.g-1. The catalytic results showed significant dye degradation, reaching 95% of decolorization and 72% of mineralization at 300 min of reaction. The catalyst showed high chemical stability in four reaction cycles. Therefore, this thermally treated Fe-rich bentonite can be considered as a promising catalyst in the heterogeneous photo-Fenton reaction for the degradation of rhodamine B from aqueous solution. Resumo O objetivo deste trabalho foi avaliar a degradação do corante rodamina B em solução aquosa por reação foto-Fenton sob irradiação visível utilizando uma bentonita rica em ferro como catalisador. O material foi tratado termicamente a baixa temperatura (200 ºC) e caracterizado por DRX, isotermas de adsorção-dessorção de N2, FTIR, MEV-EDS e FRX. A lixiviação do ferro na solução aquosa após a reação foto-Fenton foi avaliada por espectroscopia de absorção atômica. O material exibiu uma estrutura mesoporosa, apresentando uma área de superfície específica de 99 m2.g-1. Os resultados catalíticos mostraram alta eficiência na degradação do corante, atingindo 95% de descoloração e 72% de mineralização em 300 min de reação. O catalisador apresentou alta estabilidade química em quatro ciclos de reação. Portanto, esta bentonita rica em Fe tratada termicamente pode ser considerada como um promissor catalisador na reação foto-Fenton heterogênea para a degradação da rodamina B em solução aquosa.

[ES] Los procesos (foto-)Fenton fueron empleados para degradar fluoroquinolonas (FQ) (una clase de antibióticos sintéticos considerados CEC) como contaminantes modelo en diferentes condiciones: pH (3 - 8), concentración de contaminante (3 - 300 μM), número de FQ presentes (1, 3 y 5), y matrices de agua (agua ultrapura, salina y de WWTP simulada). Los experimentos se realizaron a escala banco y planta piloto, empleando luz solar (simulada y real) e irradiaciones con luz ultravioleta. Las velocidades de degradación de los contaminantes obtenidas con procesos tipo-Fenton se compararon con las análogas de fotólisis, fotocatálisis heterogénea y H2O2/UV. En igualdad de condiciones, solo a través del proceso foto-Fenton se logró una mineralización significativa de las FQs. En aquellos casos en los que el carbono orgánico total no mostró una disminución considerable, la razón se atribuye a la liberación de subproductos de oxidación. EEM-PARAFAC ha demostrado ser una técnica económica, veloz y que no requiere del uso de reactivos, para seguir simultáneamente la eliminación de la degradación de hasta 5 FQs fluorescentes presentes en una misma muestra, en presencia de interferencias sin calibrar, y obtener información sobre las posibles estructuras moleculares de los intermediarios de reacción. Los resultados indicaron que la fotólisis por sí sola no es capaz de producir cambios importantes en la estructura de las FQs, mientras que con (foto-)Fenton sí que se observó una notable disminución de los scores de los componentes PARAFAC asociados con los compuestos del tipo FQ. Los ensayos de zona de inhibición empleando E. coli mostraron que la actividad antibiótica disminuyó en paralelo con la desintegración de todos los componentes PARAFAC relacionados con las FQs y subproductos similares a estas. El otro aspecto importante de la tesis fue el uso de procesos Fenton basados en ZVI. Algunos CEC, como los compuestos nitroaromáticos, exhiben tasas de degradación lentas incluso cuando son degradadas por una AOP. El desarrollo de trenes de tratamiento ZVI para la degradación de contaminantes ha despertado un gran interés en los últimos años. Este enfoque consiste en un primer pretratamiento solo con ZVI (es decir, reducción, deshalogenación), seguido del proceso Fenton aprovechando los iones de hierro liberados en el primer paso. Con el fin de analizar las posibles ventajas e inconvenientes de esta estrategia en las aplicaciones de tratamiento de aguas residuales, se ha estudiado este enfoque empleando micropartículas de ZVI (mZVI) comerciales utilizando ácido p-nitrobenzoico (PNBA) como contaminante modelo. Se analizó el efecto de la cantidad inicial de mZVI, H2O2, pH, conductividad, aniones y oxígeno disuelto. Utilizando agua natural en condiciones aeróbicas, pH inicial 3,0, y adicionando 1,4 g/L de mZVI, se consiguió en 2 h una reducción del 83% de PNBA 6 μM en ácido p-aminobenzoico (PABA). Se investigó también la conveniencia de separar las mZVI después de la fase reductora (antes de la etapa Fenton) así como la reutilización de las mZVI. El paso de Fenton contra el PABA, más reactivo que PNBA, requirió 50 mg/L de H2O2 para lograr una eliminación de más del 96% en 15 min a pH 7,5 (pH final del pretratamiento reductivo). Las mZVI reutilizadas fueron efectivas por lo menos por un ciclo completo (reducción/oxidación). Este enfoque puede ser interesante para tratar aguas residuales que contienen contaminantes inicialmente resistentes al radical hidroxilo (HO), pero fácilmente reducibles, pudiendo disminuir su carga tóxica y aumentar su reactividad para un paso de oxidación posterior., [CA] Fenton i foto-Fenton van ser emprats per a degradar fluoroquinolones (FQ) (una classe d'antibiòtics sintètics considerats CEC) com a contaminants model en diferents condicions: pH (3 - 8), concentració de contaminant (3 - 300 μM), nombre de FQ presents (1, 3 i 5), i matriu d'aigua (aigua ultrapura, salada i de WWTP simulada). Els experiments es van realitzar a escala de laboratori i planta pilot, emprant llum solar (simulada i real) i irradiacions amb llum ultraviolada. Les velocitats de degradació de contaminants obtingudes amb processos tipus-Fenton es van comparar amb fotòlisi, fotocatàlisi heterogènia i H2O2/UV. En igualtat de condicions, només a través del procés foto-Fenton es va aconseguir una mineralització significativa de FQ. En aquells casos en els quals el carboni orgànic total no va mostrar una disminució considerable, la raó s'atribueix a l'alliberament de subproductes d'oxidació. EEM-PARAFAC ha demostrat ser una tècnica econòmica, que no requereix de l'ús de reactius, i ràpida, per a seguir simultàniament l'eliminació de la degradació de fins a 5 FQ fluorescents presents en una mateixa mostra, en presència d'interferències sense calibrar, i obtindre informació sobre les possibles estructures moleculars dels intermediaris de reacció. Els resultats van indicar que la fotòlisi per si sola no és capaç de produir canvis importants en l'estructura de les FQ, mentre que amb (foto-)Fenton, sí que es va observar una notable disminució dels scores dels components PARAFAC associats amb el nucli de FQ. Els assajos de zona d'inhibició que empren E. coli van mostrar que l'activitat antibiòtica va disminuir en paral·lel amb la desintegració de tots els components PARAFAC relacionats amb FQ i subproductes similars a FQ. L'altre aspecte important de la tesi va ser l'ús de processos Fenton basats en ZVI. Alguns CEC, com els compostos nitroaromàtics, exhibeixen taxes de degradació lentes fins i tot quan són degradats per un AOP. El desenvolupament de trens de tractament basats en ZVI per a la degradació de contaminants ha despertat un gran interés en els últims anys. Aquesta aproximaciót consisteix en un primer pretractament amb ZVI (és a dir, reducció, deshalogenación), seguit del procés Fenton aprofitant els ions de ferro alliberats en el primer pas. Amb la finalitat d'analitzar els possibles avantatges i inconvenients d'aquesta estratègia en les aplicacions de tractament d'aigües residuals, s'han emprat micropartícules de ZVI (mZVI) comercials. Utilitzant àcid p-nitrobenzoic (PNBA) com a contaminant model, es va analitzar l'efecte de la quantitat inicial de mZVI, H2O2, pH, conductivitat, anions i oxigen dissolt. Utilitzant aigua natural en condicions aeròbiques, pH inicial 3,0, i addicionant 1,4 g/L de mZVI, es va aconseguir en 2 h una reducció del 83% de PNBA 6 μM a àcid p-aminobenzoic (PABA). Es va investigar també la conveniència d'eliminar les mZVI després de la fase reductora (abans de l'etapa Fenton) així com la reutilització de les mZVI. El pas de Fenton front el PABA, més reactiu que PNBA, va requerir 50 mg/L de H2O2 per a aconseguir una eliminació de més del 96% en 15 min a pH 7,5 (pH final del pretractament reductiu). Les mZVI reutilitzades van ser efectives almenys amb un cicle complet (reducció/oxidació). Aquest enfocament pot ser interessant per a tractar aigües residuals que contenen contaminants inicialment resistents al HO, però que es redueixen fàcilment, podent disminuir la seua càrrega tòxica i augmentar la seua reactivitat per a un pas d'oxidació posterior., [EN] Dark Fenton and photo-Fenton were employed to degrade Fluoroquinolones (FQs) (a class of synthetic antibiotics considered CEC) as model pollutants under different conditions: pH (3 - 8), pollutant concentration (3 - 300 μM), number of present FQs (1, 3 and 5), and water matrix (ultra-pure, salty and simulated wastewater). Experiments were performed at bench and pilot plant scales, employing sunlight (simulated and real) and ultraviolet light irradiations. Obtained pollutant abatement rates with Fenton-related processes were compared with photolysis, heterogeneous photocatalysis and H2O2/UV. At equal conditions, only through photo-Fenton process significant FQs mineralization were achieved. In those cases where total organic carbon had not exhibit a considerable decrease, the reason was attributed to the release of oxidation by-products. Since FQs are fluorescent, we decided to employ fluorescence excitation-emission matrices (EEM) in combination with the chemometric tool, Parallel Factor Analysis (PARAFAC), to track their degradations. Although EEM-PARAFAC related studies are usually focused towards the characterization and monitoring of dissolved organic matter (DOM) in natural waters and wastewater effluents (work also included in this PhD Thesis following the DOM along the different stages of a drinking water plant), it is barely the first time that it is used for the purposes we have here proposed. The objective is demonstrating that EEM-PARAFAC could be a feasible complementary methodology for the study of fluorescent CECs degradations, avoiding the use of expensive and sophisticated techniques (e.g mass spectrometry), not always available. The other important aspect of the PhD Thesis was the use of ZVI-based Fenton processes. Some CECs such as nitroaromatic compounds, exhibit slow degradation rates even with AOPs. The development of new and more efficient ZVI treatment trains for pollutant degradation has been attracting great interest in the last few years. This approach consists of a first pre-treatment only with ZVI (i.e. reduction, dehalogenation), followed by a Fenton oxidation taking advantage of the released iron ions from the first step. In order to analyse the strategy's plausible advantages and potential drawbacks within wastewater treatment applications, reductive/oxidative treatment train based on commercial ZVI microparticles (mZVI) has been studied. The effect of the initial amount of mZVI, H2O2, pH, conductivity, anions, dissolved oxygen were analysed using p-nitrobenzoic acid (PNBA) as model pollutant. 83% reduction of PNBA 6 μM into p-aminobenzoic acid (PABA) was achieved in natural water at initial pH 3.0 and 1.4 g/L of mZVI under aerobic conditions in 2 h. An evaluation of the convenience of removing mZVI after the reductive phase (before the Fenton oxidation one) was investigated together with mZVI reusability. The Fenton step against the more reactive PABA required 50 mg/L of H2O2 to achieve more than 96% removal in 15 min at pH 7.5 (final pH from the pre-reductive step). At least one complete reuse cycle (reduction/oxidation) was obtained with the separated mZVI. This approach might be interesting to treat wastewater containing pollutants initially resistant to hydroxyl radical (HO), but easily reduced, being able to decrease its toxic load as well as increasing its reactivity for a subsequent oxidation step.

This work presents a disruptive approach to promote highly-efficient photo-Fenton process at neutral pH under continuous mode operation. The system consists of a tube-in-tube membrane reactor designed for continuous-flow titration of low iron doses to the annular reaction zone (ARZ). A concentrated acidic ferrous ion (Fe2+) solution is fed by the lumen-side of the membrane, permeating through the membrane pores (inside-out mode), being dosed and uniformly delivered to the membrane shell-side. Polluted water, containing amoxicillin (AMX) and oxidant (H2O2), flows continuously in the reactor annulus (space between the membrane shell-side and an outer quartz tube). The catalyst radial dispersion is enhanced by the helicoidal movement of water around the membrane shell-side, efficiently promoting its contact with H2O2 and UV light. The efficiency of photochemical and photocatalytic oxidation was evaluated as a function of catalyst dose, catalyst injection mode (radial permeation vs injection upstream from the reactor inlet), light source (UVA vs UVC) and aqueous solution matrix (synthetic vs real wastewater). At steady-state, photo-Fenton reaction with Fe2+ radial addition, driven by UVC light, showed the highest AMX removal for synthetic (∼65%, removal rate of 44 μMAMX/min, using [Fe2+]ARZ = 2 mg/L and [H2O2]inlet = 10 mg/L) and real municipal wastewaters (∼45%, removal rate of 31 μMAMX/min, with [Fe2+]ARZ = 5 mg/L and [H2O2]inlet = 40 mg/L), with a residence time of only 4.6 s., Este trabajo presenta un enfoque disruptivo para promover el proceso foto-Fenton de alta eficiencia a pH neutro en funcionamiento en modo continuo. El sistema consta de un reactor de membrana de tubo en tubo diseñado para la titulación de flujo continuo de dosis bajas de hierro a la zona de reacción anular (ARZ). El lado del lumen de la membrana alimenta una solución concentrada de iones ferrosos ácidos (Fe 2+ ), que penetra a través de los poros de la membrana (modo de adentro hacia afuera), se dosifica y se entrega uniformemente al lado de la carcasa de la membrana. Agua contaminada, que contiene amoxicilina (AMX) y oxidante (H 2 O 2), fluye continuamente en el anillo del reactor (espacio entre el lado de la carcasa de la membrana y un tubo de cuarzo exterior). La dispersión radial del catalizador se ve reforzada por el movimiento helicoidal del agua alrededor del lado de la carcasa de la membrana, lo que promueve de manera eficiente su contacto con el H 2 O 2 y la luz ultravioleta. La eficiencia de la oxidación fotoquímica y fotocatalítica se evaluó en función de la dosis de catalizador, el modo de inyección del catalizador (permeación radial frente a inyección aguas arriba de la entrada del reactor), fuente de luz (UVA frente a UVC) y matriz de solución acuosa (sintética frente a aguas residuales reales). En estado estacionario, reacción de foto-Fenton con Fe 2+Además radial, impulsada por la luz UVC, mostró la más alta de eliminación AMX para sintético (~ 65%, la tasa de eliminación de 44? M AMX / min, utilizando [Fe 2+ ] ARZ = 2 mg / L y [H 2 O 2 ] de entrada = 10 mg / L) y aguas residuales municipales reales (~ 45%, la tasa de eliminación de 31? M AMX / min, con [Fe 2+ ] ARZ = 5 mg / L y [H 2 O 2 ] de entrada = 40 mg / L), con un tiempo de residencia de tan solo 4,6 s.

Resumo Este trabalho objetivou a preparação da zeólita ZSM-5 suportada com nanopartículas de óxido de ferro para uso como catalisador na degradação de um poluente orgânico em solução aquosa a partir do processo foto-Fenton. A zeólita foi preparada usando gel nucleante como indutor de formação da estrutura tipo MFI. Nanopartículas de óxido de ferro foram suportadas sobre a zeólita através da técnica de impregnação incipiente. Além disso, nanopartículas de óxido de ferro foram preparadas para fins de comparação entre as atividades catalíticas na reação foto-Fenton. Os materiais produzidos foram caracterizados por difração de raios X, microscopia eletrônica de varredura e análise de adsorção/dessorção de nitrogênio. Os resultados revelaram a formação do sistema Fe2O3/ZSM-5 com propriedades intrínsecas que resultaram em satisfatória atividade catalítica, sendo superior ao óxido de ferro. Além disso, esse sistema apresentou excelente atividade e estabilidade após três ciclos de reuso. O material Fe2O3/ZSM-5 produzido neste trabalho apresenta-se como um catalisador promissor para uso na reação foto-Fenton para a degradação de poluentes orgânicos em soluções aquosas.

W pracy porównano efektywność oczyszczania odcieków pochodzących ze „starego” składowiska odpadów komunalnych w procesie Fentona i foto-Fentona. Podczas wszystkich etapów badań stosunek masowy ChZT:H2O2 był stały (1:2). Dawki reagentów (stosunek siarczan żelaza/nadtlenek wodoru) zmieniano w zakresie od 0.1 do 0.5. Efektywność obu procesów oceniano w oparciu o stopień obniżenia BZT5 (biochemicznego zaporzebowania tlenu), ChZT (chemicznego zapotrzebowania tlenu), OWO (ogólnego węgla organicznego), azotu amonowego i zmiany wskaźnika BZT5/ChZT. Podczas oczyszczania odcieków z odczynnikiem Fentona wyznaczono najkorzystniejsze parametry prowadzenia procesu tj. temperatura (25ºC), początkowy odczyn odcieków (pH=3.0) . Czas trwania reakcji ustalono na 60 min. Stwierdzono, że dla tego rodzaju wód odpadowych najkorzystniejsza dawka reagentów to 0.25. Zauważono, że obecność dodatkowego czynnika (UV) przy każdej przebadanej dawce reagentów skutkowało średnio 14% wyższym stopniem usunięcia ChZT i OWO z badanych odcieków

espanolSe evaluo la remocion de carbono organico total (COT) presente en un efluente generado por la industria de procesamiento de subproductos de origen animal (rendering), mediante fotocatalisis (foto-Fenton) y adsorcion con carbon activado. El efluente considerado fue el vapor condensado de coccion cuya elevada carga contaminante, hace que tratamientos convencionales tales como los biologicos y quimicos sean insuficientes o economicamente inviables. Para evaluar el efecto de las variables de proceso, concentracion de Fe(II) y dosis de agente oxidante (H2O2), se utilizo la metodologia de superficie de respuesta. En el estudio de adsorcion se considero el efecto del pH, dosis de adsorbente y tiempo de contacto. Para el tratamiento fotocatalitico se alcanzo una remocion del 69.2% de COT, mientras que para el proceso de adsorcion fue del 77.9%. Despues de esto, se evaluo la remocion de COT de dos sistemas acoplados. Para uno de los sistemas, el efluente fue pre tratado mediante adsorcion y sometido posteriormente al tratamiento fotocatalitico donde se alcanzo una degradacion global del 91.9%. Esta sinergia entre los procesos de adsorcion y foto-Fenton, aparecen como una alternativa viable para el tratamiento de este tipo de efluentes industriales. EnglishIn this paper the removal of total organic carbon (TOC) present in an effluent generated by the rendering industry was evaluated, by photocatalysis (photo-Fenton) and activated carbon adsorption. The effluent considered in the study was the condensed steam cooking that has high environmental burdens so conventional biological and chemical treatments are insufficient or are economically unviable. To evaluate the effect of process variables, concentration of Fe (II) and dose of oxidizing agent (H2O2), the response surface methodology was used. In the adsorption study, the effect of pH, adsorbent dose and contact time was considered. For photocatalytic treatment the TOC removal percentage obtained was 69.2%, while for the adsorption process was 77.9%. After that, the TOC removal of two coupled systems was evaluated. For one of the systems, the effluent was pretreated by adsorption and subsequently subjected to photocatalytic treatment, reaching an overall degradation of 91.9%. This synergy between adsorption and photo-Fenton processes appears as a viable option for the treatment of this type of industrial effluents.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:22Z No. of bitstreams: 1 S0100-46702010000100003.pdf: 587765 bytes, checksum: 2907cdaf2ee7ed4a014694af1bb3a848 (MD5) Made available in DSpace on 2013-08-22T18:49:22Z (GMT). No. of bitstreams: 1 S0100-46702010000100003.pdf: 587765 bytes, checksum: 2907cdaf2ee7ed4a014694af1bb3a848 (MD5) Previous issue date: 2010-01-01 Made available in DSpace on 2013-09-30T19:39:46Z (GMT). No. of bitstreams: 2 S0100-46702010000100003.pdf: 587765 bytes, checksum: 2907cdaf2ee7ed4a014694af1bb3a848 (MD5) S0100-46702010000100003.pdf.txt: 38613 bytes, checksum: c760928a5da69a037aaf860bc803473a (MD5) Previous issue date: 2010-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:10:35Z No. of bitstreams: 2 S0100-46702010000100003.pdf: 587765 bytes, checksum: 2907cdaf2ee7ed4a014694af1bb3a848 (MD5) S0100-46702010000100003.pdf.txt: 38613 bytes, checksum: c760928a5da69a037aaf860bc803473a (MD5) Made available in DSpace on 2014-05-20T15:10:35Z (GMT). No. of bitstreams: 2 S0100-46702010000100003.pdf: 587765 bytes, checksum: 2907cdaf2ee7ed4a014694af1bb3a848 (MD5) S0100-46702010000100003.pdf.txt: 38613 bytes, checksum: c760928a5da69a037aaf860bc803473a (MD5) Previous issue date: 2010-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Laboratórios e centros de pesquisa consomem uma grande variedade de substâncias químicas perigosas e, consequentemente, geram resíduos contendo-as, como por exemplo: resíduo de formaldeído. O formol é bastante empregado na conservação de peças anatômicas, gerando muitos litros desse resíduo por ano. O presente trabalho sugere o uso do processo foto-Fenton com irradiação solar para tratar resíduo contendo formaldeído. Alguns aspectos foram estudados como a concentração da fonte de ferro, da amostra e do peróxido de hidrogênio, além da aplicação de agitação magnética. O uso de ferrioxilato (0,5 mol L-1) mostrou ser mais eficiente na degradação da matéria orgânica quando comparado ao nitrato férrico. Já a concentração de peróxido necessária para tratar 500 mg C L-1 foi de 1 mol L-1. Sob essas condições todo formaldeído detectável foi degradado e foi possível remover 89% da matéria orgânica dissolvida na amostra em duas horas. Tais resultados são considerados satisfatórios para descartar na rede de esgoto, segundo a agência paulista de controle ambiental. Laboratories consume great amounts of hazardous chemicals substances and consequently generate wastewater containing them, for example formaldehyde. This substance is widely utilized to preserve biological samples generating many liters of this residue every year. The present work proposes the use of the photo-Fenton process to treat formaldehyde wastewater using sunlight irradiation. Some aspects were investigated such as the iron source, sample and hydrogen peroxide concentration and also the use of stirred systems. The use of ferrioxalate (0.5 mmol L-1) improved the efficiency of the process in relation to the use of iron nitrate, while at least 1.0 mol L-1 H2O2 is necessary to treat the sample of the 500 mg C L-1. Under these conditions, every formaldehyde detectable was degradeted and 89% of the dissolved organic carbon was removed in two hours of exposure to sunlight. These results are satisfaction considerate for São Paulo State Environmental Agency. UNESP Waste Management Program UNESP Institute of Chemistry UNESP Waste Management Program UNESP Institute of Chemistry

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:14Z No. of bitstreams: 1 S0100-46702004000200003.pdf: 588952 bytes, checksum: a43f0469dc2354214ae17f24a287e17b (MD5) Made available in DSpace on 2013-08-22T18:49:14Z (GMT). No. of bitstreams: 1 S0100-46702004000200003.pdf: 588952 bytes, checksum: a43f0469dc2354214ae17f24a287e17b (MD5) Previous issue date: 2004-01-01 Made available in DSpace on 2013-09-30T19:39:29Z (GMT). No. of bitstreams: 2 S0100-46702004000200003.pdf: 588952 bytes, checksum: a43f0469dc2354214ae17f24a287e17b (MD5) S0100-46702004000200003.pdf.txt: 21480 bytes, checksum: ce09cb8f8b8acf1a3e5ec1491ad70c45 (MD5) Previous issue date: 2004-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:10:30Z No. of bitstreams: 2 S0100-46702004000200003.pdf: 588952 bytes, checksum: a43f0469dc2354214ae17f24a287e17b (MD5) S0100-46702004000200003.pdf.txt: 21480 bytes, checksum: ce09cb8f8b8acf1a3e5ec1491ad70c45 (MD5) Made available in DSpace on 2014-05-20T15:10:30Z (GMT). No. of bitstreams: 2 S0100-46702004000200003.pdf: 588952 bytes, checksum: a43f0469dc2354214ae17f24a287e17b (MD5) S0100-46702004000200003.pdf.txt: 21480 bytes, checksum: ce09cb8f8b8acf1a3e5ec1491ad70c45 (MD5) Previous issue date: 2004-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Neste trabalho estudou-se a aplicabilidade do processo foto-Fenton utilizando irradiação solar no tratamento de dois efluentes (A e B) de uma indústria de tintas. Foi avaliada a influência da concentração inicial de peróxido de hidrogênio e ferro na remoção de carbono orgânico dissolvido (COD). Nos primeiros minutos de irradiação foi observada a descoloração e a remoção de odores. Para o efluente A, atingiu-se 75 % de remoção de COD durante 60 minutos de irradiação. Para o efluente B, adições múltiplas de peróxido de hidrogênio foram necessárias para aumentar a remoção de COD, 43 % em 60 minutos de irradiação. Os resultados obtidos mostram que o processo foto-Fenton solar pode ser aplicado ao tratamento dos efluentes gerados na indústria de tintas. The photo- Fenton process was evaluated for the treatment of two effluents (A and B) from ink industry. The influence of hydrogen peroxide and iron (II) concentration on the dissolved organic carbon (DOC) removal was evaluated. In the first minutes of irradiation the color and odors were removed. For the effluent A 75% of DOC removal was reached in 60 min irradiation. For the effluent B, multiple additions of H2O2 were necessary to improve the COD removal, reaching 43% of TOC in 60 min irradiation. The results obtained demonstrate that the solar photo-Fenton process can be applied for the treatment of effluents generated by ink industry. UNESP Instituto de Química UNESP Instituto de Química

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:11Z No. of bitstreams: 0 Made available in DSpace on 2013-08-22T18:49:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-01-01 Made available in DSpace on 2013-09-30T19:09:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T14:19:40Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T14:19:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) A influência de parâmetros operacionais como a agitação da solução durante irradiação solar e a vazão de alimentação de um fotorreator com irradiação artificial foi avaliada na fotodegradação de 2-clorofenol (2CF) e 2,4-diclorofenol (DCF) por processo foto-Fenton mediado por ferrioxalato. Após avaliação destes parâmetros, os sistemas foram aplicados na fotodegradação de fenol e de mono, (2-clorofenol e 4-clorofenol), di (2,4-diclorofenol) e tri (2,4,6-triclorofenol) clorofenóis a fim de avaliar a eficiência de fotodegradação destes compostos sob irradiação solar e artificial. Foi observada pequena diferença nas porcentagens de remoção de carbono orgânico total (COT) e de geração de íons cloreto nos experimentos de fotodegradação de 2CF sem agitação e com agitação sob irradiação solar. Sob irradiação artificial, um aumento da vazão de alimentação do sistema resultou em menor porcentagem de remoção de COT, ao passo que uma maior velocidade de remoção foi obtida devido a um menor tempo de irradiação. Foi então utilizada uma vazão intermediária de 33,4 mL min-1. Sob irradiação solar, foram necessários 15 minutos de irradiação para a completa remoção de todos os clorofenóis, entretanto para fenol, a completa remoção foi atingida em 20 minutos. Sob irradiação artificial, os clorofenóis foram removidos entre 4,5 e 6,5 minutos de irradiação. A velocidade de degradação aumenta ligeiramente com o aumento do número de cloros ligados ao anel aromático tanto sob irradiação artificial como solar. The influence of some operational parameters such as stirring the solution during solar irradiation and the solution flow rate into artificial irradiation photoreactor were evaluated on the photodegradation of 2-chlorophenol (2CP) and 2,4-diclorophenol (DCP) by photo-Fenton process mediated by ferrioxalate. After evaluation of these parameters, the systems were applied to photodegradation of phenol and mono (2-chlorophenol and 4-clorophenol), di (2,4-dichlorophenol) and tri (2,4,6-trichlorophenol) chlorophenols to evaluate the photodegradation efficiency of these compounds under solar as well as artificial irradiation. Small differences in the percentages of total organic carbon (TOC) removal and generation of chloride ions were observed with and without stirring the solution during solar irradiation of 2CP. Under artificial irradiation, the increase of flow rate resulted in lower TOC removal, while a higher rate of TOC removal was obtained due to a shorter irradiation time. An intermediate flow rate of 33.4 mL min-1 was then used. Under solar irradiation, 15 minutes irradiation were necessary for complete removal of all chlorophenols, however, the complete removal of phenol was achieved in 20 minutes. Under artificial irradiation, the chlorophenols were removed between 4.5 and 6.5 minutes of irradiation. The degradation rates increased slightly with the increase of the number of chlorides bonded to the aromatic ring under solar as well as artificial irradiation. UNESP Instituto de Química Departamento de Química Analítica UNESP Instituto de Química Departamento de Química Analítica