Made available in DSpace on 2017-07-24T19:37:55Z (GMT). No. of bitstreams: 1 Vitor Sena Kosera.pdf: 2784094 bytes, checksum: 960f241504b5d1829f16f8713f9dddad (MD5) Previous issue date: 2017-03-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Triclosan is a compound with bactericidal effect that is frequently used in personal hygiene products. Recently, it has been found in surface water and wastewater even after conventional treatment. In the search for efficient alternative methods of degradation, are studied among them Oxidative Advanced Processes (AOPs), which are based on hydroxyl radical generation (HO), which is a strong oxidizing agent. The objective of this work was to study the degradation of triclosan using Heterogeneous Photocatalysis (HP), characterized by the use of a free and immobilized photocatalyst. In this work titanium dioxide (TiO2) and zinc oxide (ZnO) were used as photocatalysts. An analytical routine was established using High Performance Liquid Chromatography (HPLC) followed by partial validation. The determination of the TCS in aqueous solution was performed in the linear range of 0.1 to 10.0 mg L-1, with R2 = 0.999, limit of detection (LOD) 0.3 mg L-1 and limit of quantification (LOQ) 1. 0 mg L-1. The characterization of the catalysts allowed to identify for the TiO2 the anatase phase, with a bandgap of 3.22 eV. The immobilization of this catalyst in calcium alginate does not cause great damage to its activity, since the characterization of the spheres demonstrated that in fact the TiO2 was present in them, in an amount of 0,267 ± 0,058 mg per sphere, according to FEG images, had a rough surface. Complementing the characterization, the images by EDS also showed that the catalyst was evenly distributed throughout the surface. In the studies with ZnO as catalyst, we identified the wurtzite phase, with bandgap of 3.14 eV. In the same way as previously, the immobilization does not cause damage to its catalytic activity, as well as the morphology of its spheres are being very close to TiO2 and also with surface distribution in all the analyzed areas (0.267 ± 0.058 mg ZnO per sphere). Also, a factorial design of experiments was carried out, where the best conditions found for both catalysts were pH 10 and 30 mg L-1. The kinetics of degradation demonstrated that the photolysis followed a first-order reaction whereas for the others the order followed was of pseudo-first order. The half-life times between free and immobilized studies did not show large variations, but TiO2 was slightly higher than ZnO. As good results with artificial radiation were achieved, studies with solar radiation were performed. The photolysis continued with a first order of reaction (t1/2 = 16.98 min) while the FH with immobilized TiO2 continued to follow a pseudo-first order (t1/2 = 22.88 min). The ZnO changed to second order (T1/2 = 11.72 min), demonstrating good efficiency using a renewable source of radiation. In the mineralization studies, TOC analysis were used to monitor the total organic matter removal of the samples. In these studies TiO2 presented a great advantage in relation to photolysis, because with about 18h of reaction, the photocatalysis was able to mineralize amounts greater than 90% while the photolysis was only about 40%. This difference was not so great for ZnO, because with this time there was a gain of approximately 10%, but it also showed superiority. These differences are easily observed using the half-life times, where for the photolysis the mineralization followed a first-order reaction with t1/ 2 = 1565 min, while the TiO2 and ZnO followed a second-order reaction with t1/2 = 76.14 min and t1/2 = 1354 min respectively. / O triclosan é um composto com ação bactericida e bastante utilizado em produtos de higiene pessoal. Recentemente, tem sido encontrado em águas superficiais e efluentes mesmo após tratamento convencional. Na busca de métodos mais eficientes de degradação, métodos alternativos têm sido estudados, estando entre eles os Processos Avançados de Oxidação (PAOs), os quais são baseados na geração do radical hidroxila (HO•), que é um forte agente oxidante. Sendo assim o objetivo deste trabalho foi estudar a degradação do triclosan utilizando a Fotocatálise Heterogênea (FH), caracterizada pelo uso de um fotocatalisador em suspensão e imobilizado. Neste trabalho foram utilizados como fotocatalisadores o dióxido de titânio (TiO2) e o óxido de zinco (ZnO). Foi realizado o estabelecimento de uma rotina analítica utilizando-se cromatografia líquida de alta eficiência (CLAE) seguido da validação parcial. A determinação do TCS em solução aquosa foi realizada na faixa linear de 0,1 a 10 mg L-1, com R2=0,999, limite de detecção (LD) 0,3 mg L-1 e limite de quantificação (LQ) 1,0 mg L-1. A caracterização dos catalisadores permitiu identificar para o TiO2 a fase anatase, com bandgap de 3,22 eV. A imobilização deste catalisador em alginato de cálcio não trouxe grandes prejuízos a sua atividade, pois a caracterização das esferas demonstrou que de fato o TiO2 estava presente nelas, numa quantidade de 0,267±0,058 mg por esfera, a qual possuía, segundo imagens por FEG, uma superfície rugosa. Complementando a caracterização as imagens por EDS demonstraram também que o catalisador estava distribuído de forma uniforme por toda a superfície. Nos estudos com o ZnO como catalisador, identificou-se a fase wurtzita, com bandgap de 3,14 eV. Da mesma maneira que anteriormente, a imobilização não acarretou em prejuízos na sua atuação catalítica, além da morfologia de suas esferas serem muito próximas das do TiO2 e também com distribuição superficial por todas as áreas analisadas (0,267±0,058 mg de ZnO por esfera). Também foi realizado um planejamento fatorial de experimentos onde para ambos catalisadores as melhores condições encontradas foram de pH 10 e 30 mg L-1. As cinéticas de degradação demonstraram que a fotólise segue uma reação de primeira ordem enquanto que para as demais a ordem foi de pseudo-primeira ordem. Os tempos de meia-vida entre os estudos em suspensão e imobilizados não apresentaram grandes variações, mas o TiO2 foi ligeiramente superior ao ZnO. Como bons resultados com radiação artificial foram alcançados, estudos com radiação solar foram realizados. Nestes a fotólise segue uma cinética de reação de primeira ordem (t1/2 = 16,98 min) enquanto que as FH com TiO2 imobilizado segue uma reação de pseudo-primeira ordem (t1/2= 22,88 min). Para o ZnO a ordem da reação encontrada foi de segunda ordem (t1/2=11,72 min), demonstrando boa eficiência quando utiliza-se uma fonte renovável de radiação. Nos estudos de mineralização, avaliou-se a remoção do carbono orgânico total (COT) após tempos pré-determnados. Nestes estudos o TiO2 utilizado como semicondutor em suspensão apresentou ampla vantagem em relação a fotólise, pois com cerca de 18h de reação, a fotocatálise conseguiu mineralizar quantidades superiores a 90% enquanto que a fotólise foi de apenas cerca de 40%. Esta diferença não foi tão significativa para o ZnO, pois neste a diferença foi aproximadamente 10%, mas demonstrou também superioridade em relação a fotólise. Estas diferenças são facilmente observadas utilizando os tempos de meia-vida, onde para a fotólise a mineralização seguiu uma reação de primeira ordem com t1/2 = 1565 min, enquanto que o TiO2 e o ZnO seguiram uma reação de segunda ordem com t1/2 = 76,14 min e t1/2=1354 min, respectivamente.

It is generally accepted that a decrease in temperature causes the rates of chemical and biochemical reactions to slow down, usually resulting in poorer performance of biological wastewater treatment systems. Despite this, early researchers repeatedly showed that excess biological phosphorus removal (EBPR) was more efficient at colder temperatures. Recent studies, however, have demonstrated that the reaction rates of EBPR processes decrease with temperature in accordance with Arrhenius' Law, resulting in an apparent contradiction in the literature. The objective of this study was to investigate the EBPR temperature controversy. The experimental systems used were two, lab-scale UCT configuration plants fed with acetate as the sole volatile fatty acid (VFA) source. The results showed that EBPR systems do perform more efficiently at colder temperatures, i.e., at 5°C compared to 20°C. The reason for better system performance was determined to be related to reduced competition for substrate in the non-oxic zones that results in an increased population of phosphate accumulating organisms (PAOs) relative to non-PAOs and, therefore, greater EBPR efficiency even though the reaction rates are slower. The proliferation of PAOs relative to non-PAOs at cold temperature indicates that some of the PAOs are psychrophilic, i.e., they have alternate biochemical pathways that give them a competitive advantage over bacteria dependent upon glycogen metabolism. The activated sludge acclimated to 20°C had relatively high polyhydroxyvalerate (PHV) and glycogen contents relative to sludge acclimated to 5°C. It was initially hypothized that there is a significant competition between PAO and glycogen accumulating organisms (GAOs) at 20°C and cold temperature (5°C) nearly eliminates this competition in favor of the PAOs. A series of batch test experiments revealed that despite similar acetate utilization by the sludges grown at the two temperatures nearly 30% less PHA was produced by the sludge taken from the 20°C reactor, indicating that GAOs were a small fraction of the population at 20°C. Transmission electron microscopy pictures showed that the biomass acclimated to 20°C had a much more diverse bacterial population than the biomass acclimated to 5°C. However, no GAO population was detected in electron microscopy samples under any temperature conditions. The decreased P removal efficiency at 20°C was then attributed to the presence of fermentative or other non poly-P bacteria that are capable of utilizing substrate under anaerobic conditions. PHA production greatly increased at 5°C, whereas glycogen metabolism substantially reduced. Even though glycogen is an essential requirement for EBPR mechanism, the EBPR microorganisms have the ability to adapt their metabolic pathways to environmental conditions and greatly reduce their need for glycogen. It is apperant that cold temperature inhibits some of the key enzymes in glycogen metabolism resulting in lower glycogen accumulation that in turn increases the EBPR performance. Therefore temperature not only exerts selective pressure on the dominant population but also alters the metabolic pathways of the EBPR process. Increased glycogen accumulation, as observed in this study at 20°C, may not be related to GAO proliferation as suggested by Filipe et al. (2001) instead it may be related to EBPR bacteria to efficiently use glycogen metabolism. Current models (Brdjanovic et al. 1997; Filipe et al. 2002) consider that GAO metabolism is an integral part of EBPR metabolism and the performance of EBPR processes depends on PAO/GAO fraction in the EBPR system. No GAO proliferation was observed even the A/O process was operated without P addition for more than 3 weeks at 10°C. Therefore such important concept should be further investigated before it is included in EBPR models. EBPR stoichiometry was presumed to be insensitive to temperatures (Brdjanovic et al. 1997). However, observed stoichiometric values of PHA storage per unit glycogen utilization and PHA utilization per unit glycogen rephlenishment were quite different at different temperatures. Temperature, therefore, not only affects the kinetics of EBPR systems but also affects the EBPR stoichiometry. Most prokaryotic cells have the ability to alter their cellular membrane fatty acid composition as temperature decreases to counteract the adverse effects of temperature on membrane fluidity (Becker et al., 1996). This unique ability is known as "homeoviscous adaptation". In this study, homeoviscous adaptation by EBPR activated sludge was investigated for a series of temperatures ranging from 20°C to 5°C using one of the lab scale EBPR systems. The fatty acid analysis results showed that the unsaturated to saturated fatty acid ratio increased from 1.40 to 3.61 as temperature dropped from 20 to 5°C. The increased cis-9-hexadecanoic acid (C16:1) at 5°C strongly indicated the presence of homeoviscous adaptation in the EBPR bacterial community. Thus the cell membranes of the EBPR community were still in a fluid state, and solute transport and proton motive force mechanisms were operable even at 5°C. It was concluded that loss of EBPR performance at low temperatures, as reported by McClintock et al. (1992) was not related to the physical state of the cellular membranes, but was probably caused by unsuitable operational conditions. Even though the transport of volatile fatty acids (e.g. acetate) is an integral part of EBPR biochemistry and stoichiometry, this important concept has been ignored. Fleet (1997) concluded that acetate entry into bacterial cells in EBPR sludge was simple passive diffusion based upon the results of a single study (Baronofsky et al. 1984). However, this study showed that neither acetate nor propionate can cross the cell membrane via simple passive diffusion. The existence of apparent saturation curves when the substrate uptake rates (acetate and propionate) were plotted against the substrate concentrations suggested that transport of volatile fatty acids obey facilitated or active transport. Following from the above results, an investigation of the impacts of operational conditions such as low solids retention time (SRT), presence of electron acceptors in the non-oxic zones, low anaerobic detention time, and lack of acclimation was performed. The results showed that the "critical, i.e., wash-out" SRT increased as temperature decreased, but if the biomass was permitted to acclimate to the lower temperature, a major population shift would occur which would increase the capacity of the system for phosphorus (P) removal. When the 5 °C sludge was allowed to acclimate at a relatively high SRT (18 d), the system's P-removal capacity greatly surpassed that of the 20 °C system. The decrease in EBPR performance because of the presence of nitrates in the non-oxic zones was determined to be greater than what would be predicted based on accepted stoichiometry. / Ph. D.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work, methods were developed for the determination of antiandrogens in hospital effluent using the analytical technique HPLC-DAD. Microextraction techniques of Spironolactone, Flutamide, Cyproterone and Tamoxifen were investigated: liquid-liquid (LLME) and sorptive extraction (SBSE). For quantification of the analytes in hospital effluent was used solid phase extraction (SPE) with recoveries of 75.0 to 109.0±1.0 to 13.0% in aqueous solution and from 72.0 to 106.0±2.0 to 13.0% in hospital effluent. The average concentrations of analytes in the effluent of emergency (PA) ranged from 0.00 to 11.70 μg L-1 (RSD 0.00 to 11.5%) and of general-HUSM 0.00 to 11.30 μg L-1 (0.00 to 6.78% RSD), respectively. LC-ESI-MS/MS technique was used for fragmentation of the precursor ions, to identify product ions, and for neutral mass loss. LC-ESI-QqLIT-MS/MS was used to identify metabolites and subproducts. STR photoreactor of 800 mL was used for simple photolysis and heterogeneous photocatalysis, and for ozonation, column reactor of 800 mL. Fractional factorial design was applied to the extraction experiments, as well as, to AOPs. UV-radiation was generated by mercury vapor lamp of 125 W and 401 W m-2. Polymer bars of polydimethylsiloxane and polyurethane with TiO2 supported were developed for photocatalysis. Kinetic studies of the degradation reactions were made, subproducts were identified and fragmentation routes proposed. Metabolites were identified in hospital effluent. Preliminary risk analysis revealed that spironolactone has lower environmental risk, and that all analytes except tamoxifen, show PEC value > 0.01 μg L-1. / Neste trabalho foram desenvolvidos métodos para a determinação de antiandrogênios em efluente hospitalar utilizando-se a técnica analítica de HPLC-DAD. Técnicas de microextração de Espironolactona, Flutamida, Ciproterona e Tamoxifeno foram investigadas: líquido-líquido (LLME) e extração sortiva (SBSE). Para a quantificação dos analitos em efluente hospitalar foi usada extração em fase sólida (SPE) com recuperações de 75,0- 109,0±1,0-13,0%, em solução aquosa, e de 72,0-106,0±2,0-13,0%, em efluente hospitalar. As concentrações médias dos analitos no efluente do pronto atendimento (PA) e geral-HUSM variaram de 0,00-11,70 μg L-1 (RSD 0,00-11,5%) e 0,00-11,30 μg L-1 (RSD 0,00-6,78%), respectivamente. A técnica de LC-ESI-MS/MS foi utilizada na fragmentação dos íons precursores, na identificação dos íons-produto e perda de massa neutra. LC-ESI-QqLITMS/ MS foi usada na identificação de metabólitos e no estudo dos subprodutos. Fotorreator STR de 800 mL foi usado para fotólise simples e fotocatálise heterogênea e, para ozonização, reator tipo coluna de 800 mL. Planejamento fatorial fracionado foi aplicado nos experimentos de extração, bem como, de PAOs. Radiação UV foi gerada com lâmpada de vapor de mercúrio de 125 W e 401 W m-2. Barras poliméricas de polidimetilsiloxano e poliuretano com TiO2 suportado foram desenvolvidas para a fotocatálise. Estudos cinéticos das reações de degradação foram feitos, subprodutos foram identificados e rotas de fragmentação propostas. Metabólitos foram identificados no efluente hospitalar. Análise preliminar de risco revelou que a espironolactona apresenta menor risco ambiental e que todos os analitos, exceto tamoxifeno, apresentam valor de PEC > 0,01 μg L-1.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this study, it was developed an analytical methodology for the quantification of parabens (PBs) in hospital effluent (University Hospital of Santa Maria - HUSM), by using solid phase extraction (SPE) followed by liquid chromatography coupled to diode array detector (HPLC-DAD). The main SPE variables were investigated by multivariate planning and optimized for the extraction/recovery of methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), butylparaben (BuP) and benzylparaben (BeP). The recovery rates varied from 75% upto 109% (± 1,0% upto 13,0%) for aqueous solution, and from 72% upto 106% (± 7,0% upto 15,5%) for hospital effluent. MeP e PrP showed the highest concentrations related to the other PBs on the sampling points HUSM General‟ (HG) e Receptor Water Course‟ (CR). The BuP concentration laid below the limit of detection (LD). Liquid Chromatography coupled to a sequential mass spectrometer provided with electrospray ionization (LC-ESI-MS/MS) was used for the identification of the metabolite, p-hydroxybenzoic acid, in hospital effluent. Photolysis and Heterogeneous photocatalysis were applied to the degradation of PBs and the variables were investigated with multivariate planning. A stirring tank reactor provide with a thermostatic jacket was used for the advance oxidation processes. Adsorption bars with titan dioxide (TiO2) supported on polydimethylsiloxane (PDMS) and polyurethane (PU) polymers were used and the efficiency was compared to the catalyst in suspension. Kinetic studies of the oxidation reactions were conducted and a total of eleven degradation products were identified by LC-ESI-MS/MS. A preliminary risk evaluation revealed that all the PBs showed a low environmental risk, MEC/PNEC < 1. / Neste trabalho foi desenvolvida metodologia analítica para a quantificação de parabenos (PBs), em efluente hospitalar (Hospital Universitário de Santa Maria - HUSM), utilizando extração em fase sólida (SPE) seguida de cromatografia líquida com detector de arranjo de diodos (HPLC-DAD). As principais variáveis da SPE foram investigadas com planejamento multivariado e otimizadas para a extração/recuperação de metilparabeno (MeP), etilparabeno (EtP), propilparabeno (PrP), butilparabeno (BuP) e benzilparabeno (BeP). As taxas de recuperação variaram entre 75% e 109% (± 1,0% e 13,0%) para solução aquosa e, entre 72% e 106% (± 7,0% e 15,5%), para efluente hospitalar. MeP e PrP apresentaram concentrações mais elevadas em relação aos demais PBs nos pontos de coleta HUSM Geral‟ (HG) e Corpo Receptor‟ (CR). A concentração de BuP ficou abaixo do limite de detecção (LD). A Cromatografia líquida acoplada a espectrômetro de massas sequencial com ionização por eletrospray (LC-ESI-MS/MS) foi usada para a identificação do metabólito, ácido p-hidroxibenzóico, em efluente hospitalar. Fotólise e fotocatálise heterogênea foram aplicadas na degradação de PBs e as variáveis (temperatura, pH, catalisador) foram investigadas com planejamento multivariado. Um reator tanque agitado provido de jaqueta termostática foi empregado nos processos de oxidação avançada. Barras de adsorção com dióxido de titânio (TiO2) suportado em polímeros de polidimetilsiloxano (PDMS) e poliuretano (PU) foram preparadas a fim de comparar sua eficiência com o catalisador em suspensão. Foram feitos estudos cinéticos das reações de oxidação e os produtos de degradação foram identificados por LC-ESI-MS/MS, num total de onze produtos de oxidação. A análise preliminar de risco revelou que todos os PBs apresentam baixo risco ambiental, MEC/PNEC < 1.

Tesis por compendio / [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. / Sciscenko, IM. (2021). Emerging Photochemical Processes Involving Iron for Wastewater Treatment [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/177357 / TESIS / Compendio