No description available.

The Department of Defense (DoD) has numerous sites that contain groundwater contaminated with 2,4,6-trinitrotoluene (TNT). The currently applied technologies for treating TNT contaminated waters are carbon adsorption and chemical oxidation. Carbon adsorption is a non-destructive technology, which could create future liability issues and is inefficient at relatively low TNT concentrations. On the other hand, application of chemical oxidation for the treatment of TNT contaminated water generates trinitrobenzene (TNB), a by-product of the incomplete oxidation of TNT. TNB is regulated as strictly as TNT. Additionally, over 70% of the reactor required treatment time for meeting target levels is due solely for TNB removal. This study evaluated the potential integration of zero-valent metallic species and advanced oxidation for the treatment of waters contaminated with TNT. The idea was to reduce treatment time, and thus, operational costs, when advanced oxidation is used as a stand-alone treatment technology by reducing TNT prior to oxidation. The use of zero-valent metals as the first treatment step transformed TNT into reduced organic compounds which were easily oxidized. The effectiveness of zinc, iron, nickel, copper, and tin as TNT reducing agents was evaluated. Zinc and iron were selected for further study based on their performance degrading TNT. Then, the reduction mechanism (pathway) and associated by-products of TNT reduction using zinc were examined using a zinc specimen manufactured by Sigma Corporation. Three amines were identified during reduction : 2-amino-4,6-dinitrotoluene, 4-amino-2,6-dinitrotoluene, and 2,4-diamino-toluene. Other intermediates were observed but not identified. Many of these reduction by-products adsorbed strongly onto the metal surface, significantly reducing the rate of TNT degradation during aging experiments. The aging of the metallic species was modeled using a power decay law parameter with the rate expression for TNT degradation. Corrosion promoters such as KCl addition, ozonation, and peroxone were evaluated as alternatives to reactivate zinc and iron to achieve steady TNT degradation. The addition of KCl performed significantly better than ozonation and peroxone. Furthermore, addition of KCl during the reduction step using iron or zinc generated organics that were successfully mineralized by ozonation or peroxone.

No description available.

The presence of emerging contaminants (ECs) in water and wastewater systems has become a subject of significant concern worldwide. These emerging contaminants are complex organic molecules which potentially affect human health and environment. Conventional wastewater treatment plants are unable to completely remove these contaminants from water and therefore can discharge them into environment. The need to develop effective methods for ECs removal is essential. This study assess the potential of ozone based advanced oxidation processes (AOP) to oxidize number of emerging contaminants. Different combinations of ozone with hydrogen peroxide and sodium persulfate were tested. For this study 1-4, dioxane, perfluorinated compounds (PFCs), N,N-Diethyl-metatoluamide, and three pharmaceuticals sulfamethoxazole, trimethoprim and carbamazepine have been selected. The effect of different process parameters such as chemical dosages, ozone weight percent, ozone flow rates, etc. on destruction of ECs were examined. It was observed that 1, 4-dioxane were persistent to direct ozone reaction, however were easily oxidized by hydroxyl radical. However, ozonation was solely very effective (> 99 %) in removing pharmaceuticals such as sulfamethoxaole, trimethoprim and carbamazepine. It was not very efficient for the removal of perfluorinated compound and N,N-Diethylmeta-toluamide. The operational conditions were optimized for maximum removal of every compound and their influence on the degradation process is discussed. / Civil Engineering

En las últimas décadas, los procesos redox fotoinducidos mediados por luz visible han recibido gran atención debido a las suaves condiciones de operación en que se llevan a cabo. Como resultado, se han logrado posicionar como una alternativa más dentro de los Procesos de Oxidación Avanzada. Además, se han convertido en una metodología excepcional en síntesis orgánica, que ha abierto la puerta a nuevas rutas químicas con aplicaciones sintéticas. Sin embargo, a pesar del crecimiento del campo, se ha prestado poca atención a los mecanismos por los que operan estos procesos. El principal objetivo de esta tesis fue avanzar en la comprensión de distintos procesos fotoredox llevados a cabo empleando fotocatalizadores orgánicos. Más específicamente, se estudió la viabilidad de distintos fotocatalizadores orgánicos, y además, se realizó un estudio mecanístico detallado basado en técnicas resueltas en el tiempo. A partir de estos resultados, se estableció una metodología para determinar los puntos clave a considerar en un sistema fotoredox. En primer lugar, en la Parte I, se eligieron dos fotocatalizadores basados en sales de pirilio y tiapirilio, que operan mediante transferencia electrónica oxidativa, con distintos objetivos. En el Capítulo 3, se evaluó su aplicabilidad en la fotodegradación de dos contaminantes de la industria del corcho y se estudió el mecanismo por el que se produce dicha fotodegradación. En el Capítulo 4, se demostró la utilidad de la detección directa de todos los intermedios de vida corta derivados del TPP+ implicados en la oxidación fotocatalizada como herramienta para evaluar el nivel de fotodegradación. En el Capítulo 5, se empleó TPTP+ para establecer las mejores características de un fotocatalizador y la influencia de la concentración de las sustancias a oxidar en la eficiencia de los estados excitados, o en general, de los intermedios clave de vida corta. En segundo lugar, en la Parte II, en el Capítulo 6, se evaluó el potencial del Rosa Bengala en la eliminación de dos fármacos. Éste es un fotocatalizador típico en la remediación de aguas residuales conocido por actuar via mecanismo Tipo II. Se incluyó además un segundo fotocatalizador, Perinaftenona, cuyo rendimiento cuántico de oxígeno singlete es incluso mayor a Rosa Bengala. En el Capítulo 7, se llevó a cabo la fotooxidación de tres contaminantes, usando NMQ+, un fotocatalizador inusual, capaz de generar oxígeno singlete desde su estado excitado singlete. En todos los casos se pudo demostrar la mayor contribución del mecanismo Tipo I sobre el mecanismo Tipo II en la fotodegradación de los diferentes contaminantes. Finalmente, en la Parte II, el Capítulo 8 se dedicó a la reducción fotocatalítica de bromuros orgánicos, empleando Riboflavina, un colorante orgánico no metálico, como fotocatalizador. De nuevo, se prestó especial atención a la detección y comportamiento de las especies intermedias, lo que resultó de acuerdo a los datos termodinámicos. / En les últimes dècades, els processos redox fotoinduïts mitjan per llum visible han rebut gran atenció degut a les suaus condicions d'operació en que es donen. Com a resultat, s'han aconseguit col·locar com una alternativa mes dins dels Processos d'Oxidació Avançada. A més, han estat convertint-se en una metodologia excepcional en síntesi orgànica, que ha obert la porta a noves rutes químiques amb aplicacions sintètiques. No obstant això, a pesar del creixement del camp, s'ha prestat poca atenció als mecanismes pels que operen aquests processos. El principal objectiu d'esta tesi va ser avançar en la comprensió de diferents processos fotoredox duts a terme emprant fotocatalitzadors orgànics. Més específicament, es va estudiar la viabilitat de distints fotocatalitzadors orgànics, i a més, es va realitzar un estudi mecanístic al detall basat en tècniques resoltes en el temps. Amb aquests resultats, es va establir una metodologia per a determinar els punts clau a considerar en un sistema fotoredox. En primer lloc, en la Part I, es van elegir dos fotocatalitzadors basats en sals de pirili i tiapirili, els quals operen per mitjà de transferència electrònica oxidativa, amb distints objectius. En el Capítol 3, es va avaluar la seua aplicabilitat en la fotodegradació de dos contaminants de la indústria del suro i es va estudiar el mecanisme pel qual es produeix dita fotodegradació. En el Capítol 4, es va demostrar la utilitat de la detecció directa de tots els intermedis de curt temps de vida derivats del TPP+ implicats en l'oxidació fotocatalitzada com a ferramenta per avaluar el nivell de fotodegradació. En el Capítol 5, es va emprar TPTP+ per a establir les millors característiques d'un fotocatalitzador i l'influencia de la concentració de les substàncies a oxidar en la eficiència dels estats oxidats, o en general, del intermedis claus de vida curta. En segon lloc, en la Part II, en el Capítol 6, es va avaluar el potencial del Rosa Bengala en l'eliminació de dos fàrmacs. Aquest es un fotocatalitzador típic en la remediació d'aigües residuals conegut per actuar via mecanisme Tipus II. Es va incloure a més un segon fotocatalitzador, Perinaftenona, el del qual rendiment quàntic d'oxigen singlet és inclús major a Rosa Bengala. En el Capítol 7, es va dur a terme la fotooxidació de tres contaminants, usant NMQ+, un fotocatalitzador inusual, capaç de generar oxigen singlet des del seu estat excitat singlet. En tots els casos es va poder demostrar la major contribució del mecanisme Tipus I sobre el mecanisme Tipo II en la fotodegradació dels diferents contaminants. Finalment, en la Part II, el Capítol 8 es va dedicar a la reducció fotocatalítica de bromurs orgànics, emprant Riboflavina, un colorant orgànic no metàl·lic, com fotocatalitzador. De nou, es va prestar especial atenció a la detecció i comportament de les espècies intermèdies, el que va resultar d'acord amb les dades termodinàmiques. / In the last decades, photoinduced-redox processes mediated through visible light have obtained great attention due to the generally mild operating conditions that they offer. As a result, they constitute a further alternative within the so-called Advanced Oxidation processes. Besides, they are becoming an outstanding methodology in organic synthesis, which has opened the door to new synthetic and chemical routes. However, despite the growth of the field, little attention has been paid to the mechanisms pathways behind these processes. The main objective of this thesis was to gain deeper understanding of different photoredox processes carried out using organic photocatalysts. More specifically, the viability of several organic photocatalysts was studied, and besides, a careful mechanistic study based on time resolved techniques supported the postulated mechanisms. With this information, a methodology determining the key points to consider in a photoredox system were stablished. Firstly, in Part I, two photocatalysts based on pyrilium and thiapyrilium salts, which operate through an oxidative electron transfer, have been used with different objectives. In Chapter 3, the viability of the photodegradation of two common pollutants from cork industry and the mechanism behind it has been evaluated. In Chapter 4, the direct detection of all the TPP+ derived short-lived intermediates in the photocatalyzed oxidation of a mixture of pollutants using TPP+ was proposed as a methodology to assess the photodegradation extent. In the last chapter of Part I, Chapter 5, TPTP+ is used to stablish the best characteristics of a photocatalyst. Besides, the study claimed the influence of the concentration of the target substances in the efficiency of the excited states or, in general, of the key short-lived intermediates. Secondly, in Part II, in Chapter 6, Rose Bengal, a typical photocatalyst used in wastewater remediation, known for working via Type II mechanism, was evaluated for the removal of two common drugs. In addition, a second one, Perinaphtenone, which exhibits even a higher singlet oxygen quantum yield than Rose Bengal was tested. In Chapter 7, NMQ+, a non-typical photocatalyst able of generate singlet oxygen from its singlet excited state, was used in the photooxidation of three different pollutants. In every case, the major contribution of Type I vs Type II mechanism was demonstrated. Finally, in Part III, Chapter 8 was devoted to the photocatalytic reduction of organic bromides. In this case, Riboflavine, a non-metallic organic dye, was used as a photocatalyst. Analogously, careful attention was paid to the behavoiur of the intermediates, which were in agreement, as well as to the thermodynamics of the steps involved in the photocatalytic cycle. / Martínez Haya, R. (2018). Photoredox catalysis for environmental and chemical applications. A mechanistically-based approach [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/114828

Une étude détaillée a été effectuée sur l'utilisation de la technique électro-Fenton pour l'oxydation de quelques polluants organiques persistants (POP) dans le but du traitement des eaux usées. Cette technique génère, in situ et de manière électrocatalytique, les radicaux hydroxyles (OH) afin de les utiliser pour oxyder la polluants organiques. Le travail de thèse est constitué en trois parties. Dans la première partie, l'élimination de l'eau des colorants synthétiques et pesticides choisis comme polluants modèles a été effectuée en utilisant une cathode en feutre de carbone. Les cinétiques d'oxydation des colorants synthétiques (Acide Orange 7 et Bleu Basique 3) et des pesticides (picloram, prophame, azinphos-méthyl et clopyralid) ont été déterminées. La cinétique de minéralisation des solutions aqueuses des polluants organiques en question a été suivie par des analyses de carbone organique totale (COT) et demande chimique en oxygène (DCO). Une minéralisation quasi-totale a été obtenue dans tous les cas. L'identification et la quantification des sous-produits d'oxydation des colorants synthétiques et pesticides ont été effectuées par les techniques d'analyse suivantes : Chromatographie liquide à haute performance (CLHP), chromatographie en phasegazeuse-spectrométrie de masse (GC/MS), chromatographie liquide à haute performances-péctrométrie de masse (HPLC/MS) et chromatographie ionique. Ces analyses systématique ont mis en évidence que les polluants organiques initiaux ont sont convertis en trois formes d'intermédiaires réactionnels ; intermédiaires organiques, acides carboxyliques à courte chaîne et ions inorganiques. Basé sur l'identification ces des intermédiaires réactionnels, une schéma de minéralisation plausible a été proposé pour chaque colorant et pesticide étudié. Dans la deuxième partie de l'étude, la capacité de production de peroxyde d'hydrogène (H2O2) de la cathode en éponge de carbone comme matériau original de cathode pour la technique électro-Fenton a été étudiée pour la première fois. Les résultats obtenus ont indiqué que le l'éponge de carbone possède une capacité de la production d'H2O2 trois fois plus élevée par rapport à la cathode classique (feutre de carbone). La troisième et dernière partie de cette thèse a été consacrée à l'étude de l'efficacité et l'utilisation en électro-Fenton d'une anode de nouvelle génération, le diamant dopé au bore (BDD pour "Boron Doped Diamond"). Tout d'abord, l'efficacité d'oxydation et la capacité de minéralisation de l'anode BDD ont été examinées sur l'herbicide propham dans les conditions d'oxydation anodique. Ensuite, la combinaison de cathode en feutre de carbone et l'anode BDD dans la technique électro-Fenton a été examinée. Les résultats obtenus ont montré que cette combinaison conduit aux résultats significativement meilleurs que le système classique feutre de carbone - Pt. L'utilisation de l'anode BDD dans l'électro-Fenton améliore considérablement la cinétique d'oxydation et l'efficacité de minéralisation des polluants organiques et en particulier des acides carboxyliques tels que les acides oxalique et oxamique qui résistent à la minéralisation dans le cas de l'anode Pt / In this thesis, a detailed investigation has been carried out on the use of electro-Fenton technique for the oxidation of the some persistent organic pollutants for the sake of water remediation. This technique produces •OH radicals electrocatalytically and uses them to oxidize the organic pollutants. The overall study can be divided into three parts. In the first part, the removal of selected synthetic dyes and pesticides from water was investigated by using carbon felt (CF) cathode. The oxidation kinetics of the synthetic dyes (Acid Orange 7 and Basic Blue 3) and pesticides (picloram, propham, azinphos-methyl and clopyralid) were determined. Mineralization kinetics of the related organic pollutants in aqueous medium was followed by total organic carbon and chemical oxygen demand analysis. The overall mineralization was obtained in all cases. Identification and quantification of the oxidation by-products of the given synthetic dyes and pesticides were performed by high performance liquid chromatography, gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry and ion chromatography. These systematic analysis showed that the initial organic pollutants were converted into three intermediate forms; organic intermediates, short-chain aliphatic carboxylic acids and inorganic ions. Based on the intermediates identified, a plausible mineralization pathway was proposed for each dye and pesticide.In the second part of the study, the H2O2 production ability of carbon sponge (CS) as a novel cathode material for the electro-Fenton technique was investigated for the first time in the literature. The obtained results indicated that CS has a H2O2 production ability three times higher than the classical cathode CF.In the third and last part, the efficiency of boron doped diamond (BDD) as an anode in the electro-Fenton technique was investigated. Firstly, the oxidation and mineralization ability of BDD was tested for herbicide propham in anodic oxidation conditions. Then, the combination of CS and BDD electrode in the electro-Fenton technique was examined. The obtained results indicated that this combination allowed the most efficient results throughout the thesis. Moreover, the use of BDD anode in the electro-Fenton technique had considerable effect on the oxidation and mineralization of organics and especially carboxylic acids such as oxalic and oxamic acids which were highly resistant to mineralization in the case of Pt anode

Au cours des dernières décennies, les produits pharmaceutiques sont devenus une nouvelle préoccupation environnementale. Les produits pharmaceutiques ont été largement détectés dans les eaux souterraines, les eaux de surface et même dans l'eau de boisson, avec une concentration allant du ng au µg L-1 dans les effluents d'eaux usées. Les stations d’épuration ne peuvent pas éliminer complètement tous les produits pharmaceutiques en raison de leur faible concentration dans l’eau et de leur résistance à la dégradation biologique. Dans les procédés d’oxydation avancée (AOP), les méthodes les plus fréquemment utilisées incluent les réactions homogènes telles que le procédé de Fenton, de type Fenton ou le procédé Photo-Fenton.Dans ce travail, un nouveau catalyseur composite BiOCl0,75I0,25 a été synthétisé par méthode de précipitation sous pression ambiante et à basse température, suivie d'une série de caractérisations. De plus, les capacités d'adsorption et de dégradation photocatalytique du catalyseur dans l'eau ont été testées sous une lumière solaire simulée en utilisant deux polluants chimiques (Acétaminophène, acide p-hydroxyphénylacétique). / In recent decades, pharmaceuticals and personal care products (PPCPs) have emerged as a new environmental concern. Pharmaceuticals have been widely detected in ground water, surface water and even drinking water with a concentration ranging from ng to µg L-1 in wastewater effluents. Sewage treatment plants (STPs) cannot remove completely all pharmaceuticals due to their low concentration in water and resistance to biological degradation. In AOPs, the most frequently used methods include homogeneous reaction such as Fenton, Fenton like or Photo-Fenton process. In this work, composite catalyst BiOCl0.75I0.25 was synthesized by precipitation method under ambient pressure and low temperature followed with a series of characterization. Moreover, the adsorption and photocatalytic degradation abilities of new bismuth catalyst in water are tested under simulated solar light using Acetaminophen, p-hydroxyphenylacetic acid and as chemical pollutant.

Ces dernières années, de plus en plus de composés organiques réfractaires et toxiques ont été détectés dans les eaux usées. Un bon nombre de ces polluants organiques sont difficilement dégradés par des traitements classiques. Les procédés d’oxydation avancée à base de radicaux sulfates (SR-AOP) sont apparus comme une méthode innovante dans le domaine de la décontamination oxydative des eaux polluées. Des études antérieures ont porté sur ces SR-AOP utilisant du peroxodisulfate (PS) ou du peroxomonosulfate (PMS) comme oxydants, en particulier des couples «métaux de transition et oxydants» (systèmes Fe (II)/PS, systèmes Ni(II)/PMS et Co (II))/PMS), où il a été confirmé que SO4•-·présentent des avantages (sélectivité) par rapport au radical hydroxyle (HO•) pour la décontamination des eaux usées contenant des polluants organiques.Dans cette thèse, nous avons généré des radicaux tels que le radical sulfite SO3•-, le radical sulfate SO4•-, le radical peroxomonosulfate SO5•- à partir d’ions métalliques (Cr(VI), le Co(II), le Fe(III)) capables d’activer le sulfite pour la dégradation des composés organiques. L'efficacité d'élimination et le mécanisme d'oxydation ont été étudiés et le rôle des espèces soufrées a été élucidé. / In recent years, more and more refractory and toxic organic compounds are detected in wastewater. Many of these organic pollutants can hardly be degraded by conventional water treatments. Sulfate radical based advanced oxidation process (SR-AOPs), have emerged as a promising method in the field of oxidative decontamination of polluted water. Past studies focused on this SR-AOPs with peroxydisulfate (PS) or peroxymonosulfate (PMS) as oxidants, especially the ‘transition metal + oxidants’ (i.e. Fe(II)/PS system, Ni(II)/PMS system and Co(II)/PMS system), which has been confirmed that SO4·− has advantages over HO in the decontamination of wastewater containing organic pollutants. In this PhD thesis, oxysulfur radicals including sulfite radical SO3·−, sulfate radical SO4·−, peroxymonosulfate radical SO5·− produced by transition metal ions such as Cr(VI), Co(II), Fe(III) activated sulfite were used to degrade organic compounds. The removal efficiency, the oxidation mechanism were examined, and and the role of sulfur species were elucidated.

A degradação do herbicida Diuron comercial (Nortox SA) foi realizada utilizando os ânodos Ti/RuxTi(1-x)O2 e Ti/IrxTi(1-x)O2 (x = 0,3; 0,5 e 0,7). A investigação da degradação foi conduzida na presença e na ausência de cloreto. O estudo da remoção do herbicida em função da densidade de corrente na ausência de cloreto rendeu remoções de 41 e 49% de demanda química de oxigênio (DQO) e remoções de 10 e 14% de carbono orgânico total (COT) a 100 mA cm-2, respectivamente. Mantendo-se o tempo de eletrólise constante (4 h), a composição do ânodo Ti/Ru0,7Ti0,3O2 foi determinada como a mais ativa para remoção do Diuron e seus subprodutos. Com a adição de cloreto, a taxa de degradação dobrou, e obteve-se 100% de remoção de DQO para o ânodo Ti/Ru0,3Ti0,7O2. O herbicida Alaclor foi totalmente mineralizado por diferentes processos eletroquímicos oxidativos avançados (PEOAs), empregando célula eletroquímica em escala de bancada (100 mL) equipada com cátodo de difusão de ar capaz de eletrogerar H2O2 e ânodos de Pt e diamante dopado com boro (BDD). O melhor desempenho para o tratamento de 100 mL de solução Alaclor 0,60 mmol L-1 durante 360 min, foi obtido por meio do processo fotoeletro-Fenton (FEF) empregando ânodo de BDD na presença de 0,5 mmol L-1 de Fe2+. De acordo com as análises de CG-MS, a etapa de degradação do Alaclor envolveu quatro vias diferentes de reação (desalquilação, ciclização, cisão da ligação R-N e hidroxilação), resultando em nove subprodutos que, em seguida, levaram ao surgimento de ácidos carboxílicos que foram detectados. Diferentes quantidades de íons nitrogenados (NH4+ e NO3-) e clorados (Cl-, ClO3- e ClO4-) foram acumulados nas soluções finais da degradação, dependendo do ânodo e da corrente aplicada. O herbicida Diuron (0,185 mmol L-1 e pH 3,0), foi tratado também por diferentes PEOAs, como oxidação anódica com H2O2 eletrogerado (OA-H2O2), eletro-Fenton (EF) e fotoeletro-Fenton empregando luz UVA (FEF) ou FEF empregando luz solar (FEFS). Os ensaios foram realizados em uma célula eletroquímica em escala de bancada (100 mL) e em seguida testes em uma planta pré-piloto (2,5 L). Nos experimentos com célula eletroquímica em escala de bancada, o tratamento FEF empregando ânodo de BDD foi o método mais potente, produzindo 93% de mineralização após 360 min a 100 mA cm-2. Na planta de fluxo pré-piloto, o processo FEFS atingiu uma porcentagem de mineralização máxima de 70% a 100 mA cm-2. Os ácidos oxálico e oxâmico foram detectados como os ácidos carboxílicos finais e íons amônio e cloreto também foram encontrados, onde o último íon foi parcialmente convertido em íons clorato e perclorato na superfície do ânodo de BDD / Commercial herbicide Diuron solution (Nortox SA) was degrated using Ti/RuxTi(1-x)O2 and Ti/IrxTi(1-x)O2 (x = 0.3, 0.5, and 0.7) anodes. Degradation was investigated in the presence and in the absence of chloride. In the absence of chloride, herbicide removal yielded 41 and 49% COD (chemical oxygen demand) removal, and 10 and 14% TOC (total organic carbon) removal at 100 mA cm-2, respectively. For a constant electrolysis time (4 h), Ti/Ru0.7Ti0.3O2 anode composition removed Diuron and its byproduct the most activelly. Addition of chloride doubled the removal ratio, and the Ti/Ru0.3Ti0.7O2 anode afforded 100% COD removal. Electrochemical advanced oxidation processes (EAOPs) quickly degraded and even totally mineralized the herbicide Alachlor in electrochemical cells equipped with a carbonaceous air-diffusion cathode that was able to electrogenerate H2O2 and with a Pt or boron-doped diamond (BDD) anode. The photoelectron-Fenton (PEF) process with BDD in the presence of 0.5 mmol L-1 Fe2+ performed the best in Alachlor solutions treatment (100 mL, 0.60 mmol L-1, 360 min.). According to GC-MS analyses, Alachlor degradation involved four different reaction pathways (dealkylation, cyclization, R-N bond cleavage and hydroxylation), to give nine byproducts, including the detected carboxylic. Different amounts of nitrogenated (NH4+ and NO3-) and chlorinated (Cl-, ClO3- and ClO4-) ions accumulated in the final solutions depending on the anode and the applied current. The herbicide Diuron (0.185 mmol L-1 and pH 3.0) was treated using different EAOPs like anodic oxidation with electrogenerated H2O2 (AO-H2O2), electro-Fenton (EF), UVA photoelectro-Fenton (PEF), and solar PEF (SPEF). Experiments were performed in 100 mL electrochemical cells, and in a 2.5 L pre-pilot flow plant. In the electrochemical cells, the PEF treatment with BDD was the most potent, yielding 93% mineralization after 360 min at 100 mA cm-2. In the pre-pilot flow plant, the SPEF process furnished maximum mineralization of 70% at 100 mA cm-2. Oxalic and oxamic acids were detected as final carboxylic acids. Ammonium and chloride ions were also released; the latter ion was partially converted into chlorate and perchlorate ions at the BDD surface

La thèse a porté principalement sur la mise en œuvre de procédés d'oxydation avancée permettant l'élimination de trois anti-inflammatoires non stéroïdiens, le kétoprofène, le naproxène et le piroxicam dans l'eau. Ces trois composés sont parmi les médicaments les plus utilisés, dont la présence dans les eaux naturelles présente potentiellement un risque toxicologique. En raison de la faible efficacité d'élimination des produits pharmaceutiques par les stations traditionnels de traitement des eaux usées, les scientifiques se sont mis à la recherche de technologies de traitements efficaces et respectueuses de l'environnement. Les procédés d'oxydation avancée, comme l'ozonation-biofiltration, l'électro-Fenton et l'oxydation anodique peuvent permettre d'atteindre la destruction presque complète des polluants étudiés et de ce fait ils ont suscité un intérêt grandissant au cours des deux dernières décennies. Tout d'abord, ce travail s'intéresse à l'élimination de certains produits pharmaceutiques dans des solutions synthétiques préparées dans l'eau de robinet à l'aide des procédés électro-Fenton et oxydation anodique dans une cellule électrochimique équipée d'une anode de platine ou de diamant dopé au bore et d'une cathode de feutre de carbone. Cette étude a été menée à l'échelle du laboratoire. Les vitesses d'élimination des molécules pharmaceutiques ainsi que le degré de minéralisation des solutions étudiées ont été déterminées sous différentes conditions opératoires. Pendant ce temps, les sous-produits de l'oxidation générés au cours de la minéralisation ont également été identifiés, ce qui nous a permis de proposer les voies d'oxydation possible pour chaque composé pharmaceutique en présence du radical hydroxyl •OH. Enfin, l'évolution de la toxicité au cours des traitements a été suivie en utilisant la méthode Microtox, basée sur l'inhibition de la fluorescence des bactéries Vibrio fischeri. Dans la deuxième partie de ce travail de thèse, les trois anti-inflammatoires non stéroïdiens ont été ajoutés dans une eau déminéralisée ou dans une eau de surface. Ces eaux ont été traitées à l'aide de différentes doses d'ozone; puis le traitement à l'ozone à été combiné à un traitement biologique par biofiltration. Un biofilm biologique déposé à la surface d'un filtre de charbon actif a été utilisé pour déterminer la biodégradabilité des sous-produits d'oxydation formés dans les eaux de surface ozonée. L'identification des intermédiaires formés lors des processus de traitement et des contrôles de toxicité bactérienne ont été menées pour évaluer la voie de dégradation des produits pharmaceutiques et des effets biologiques potentiels, respectivement / The thesis mainly focused on the implementation of advanced oxidation processes for the elimination of three non-steroidal anti-inflammatory drugs-ketoprofen, naproxen and piroxicam in waters. The three compounds are among the most used medicines, whose presence in waters poses a potential ecotoxicological risk. Due to the low pharmaceuticals removal efficiency of traditional wastwater treatement plants, worldwide concerns and calls are raised for efficient and eco-friendly technologies. Advanced oxidation processes, such as ozonation-biofiltration, electro-Fenton and anodic oxidation processes, which attracted a growing interest over the last two decades, could achieve almost complete destruction of the pollutants studied. Firstly, removal of selected pharmaceuticals from tap water was investigated by electrochemical advanced oxidation processes “electro-Fenton” and “anodic oxidation” with Pt or boron-doped diamond anode and carbon felt cathode at lab-scale. Removal rates and minieralization current efficencies under different operatioanl conditions were analysed. Meanwhile, intermediates produced during the mineralization were also identified, which helps to propose plausible oxidation pathway of each compound in presence of •OH. Finally, the evolution of the global toxicity of treated solutions was monitored using Microtox method, based on the fluorescence inhibition of Vibrio fischeri bacteria. In the second part, the three nonsteroidal anti-inflammatory molecules added in organics-free or surface water were treated under varying ozone treatment regimes with the quite well established technology ozone/biofiltration. A bench-scale biological film was employed to determine the biodegradability of chemical intermediates formed in ozonized surface water. Identification of intermediates formed during the processes and bacterial toxicity monitoring were conducted to assess the pharmaceuticals degradation pathway and potential biological effects, respectively