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

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

Atualmente a classe dos antibióticos se destaca pelo grande consumo e também pelo risco à saúde quando administrado de forma equivocada, esse aumento deve-se ao destaque cada vez maior da indústria de produtos farmacêuticos. Outra questão a ser levantada é a contaminação do meio ambiente por essa classe substâncias, pois após o uso pelo ser humano ocorre a eliminação natural de parte da concentração administrada, assim sendo liberadas nos esgotos e, posteriormente, contaminando os corpos d\'água, a fauna e flora local. Assim, foi proposto um métodos diferente para a degradação desses compostos, utilizando a eletrodos de difusão gasosa (EDG) capazes de gerar peróxido de hidrogênio in situ e em meio ácido, precursores dos radicais hidroxila, responsáveis pela degradação. Foram estudados EDG\'s não catalisados e catalisados, com diferentes porcentagens de ftalocianina de ferro II, com relação à quantidade de peróxido produzido, melhor potencial de produção e cinética do processo. Os resultados revelaram que a incorporação de 0,5% de Ft-Fe no eletrodo apresentou os melhores resultados. Esse eletrodo foi escolhido então para realizar as degradações dos antibióticos sulfametoxazol e trimetoprim. Na célula eletroquímica utilizou-se o processo Fenton, as reações ocorreram em uma faixa de potencial (-0,4 V ≤ E ≤ -1,4 V) e no reator foi utilizado um potencial fixo (-1,75 V) mas utilizando processos de Fenton e Foto-Fenton. As amostras degradadas foram avaliadas por técnicas analíticas de espectroscopia no ultravioleta (UV), cromatografia líquida de alta eficiência (HPLC) e teor de carbono orgânico total (TOC). Os resultados mostraram que, na célula eletroquímica, o melhor potencial de degradação foi de -1,1 V, com uma taxa de redução de 25,5% para o trimetoprim e 96,0% do sulfametoxazol e uma diminuição do teor de carbono orgânico total de 10,4%. Para o reator o melhor resultado foi obtido para o processo de Foto-Fenton onde houve uma redução de 16,9% do teor de carbono orgânico total e uma redução de 99,7% do sulfametoxazol e 11,3% do trimetoprim, em um potencial de -1,75 V. Considerando a formação de subprodutos foi elaborada uma rota de degradação com os possíveis compostos formados. / Currently the class of antibiotics is notable for the large consumption and also the risk to health when administered in error, this increase is due to the growing prominence of the pharmaceutical industry. Another issue to be addressed is the environmental contamination by substances that class, because after use by humans part of the concentration administered is naturally eliminated, thus being released into sewers and subsequently contaminating water bodies, the local fauna and flora. Thus, different methods has been proposed for the degradation of these compounds, using gas diffusion electrodes (GDE) capable of generating hydrogen peroxide in situ and in acid medium, precursors of hydroxyl radicals, responsible for degradation. We studied GDE\'s not catalyzed and catalyzed with different percentages of iron phthalocyanine II, with respect to the amount of peroxide produced better yield potential and kinetic process. The results revealed that the incorporation of 0.5% of Ft-Fe in the electrode showed the best results. This electrode was then chosen to perform the degradation of the antibiotic sulfamethoxazole and trimethoprim. In the electrochemical cell used in the Fenton process, the reactions occurred in a potential range (-0.4 V ≤ E ≤ -1.4 V) and in the reactor was used a fixed potential (-1.75 V) but using Fenton and photo-Fenton processes. Degraded samples were analyzed by analytical techniques, ultraviolet spectroscopy (UV), high performance liquid chromatography (HPLC) and total organic carbon content (TOC). The results showed that in the electrochemical cell, the best degradation potential was -1.1 V, with a reduction rate of 25.5% for trimethoprim and 96.0% for sulfamethoxazole and a decreased carbon content total of 10.4%. For the reactor the best result was obtained for the photo-Fenton process where there was a reduction of 16.9% of the total organic carbon content and a reduction of 99.7% of sulfamethoxazole and 11.3% of trimethoprim, in a potential of -1.75 V. Considering the formation of byproducts was drafted a route with the possible degradation compounds formed.

Atualmente a classe dos antibióticos se destaca pelo grande consumo e também pelo risco à saúde quando administrado de forma equivocada, esse aumento deve-se ao destaque cada vez maior da indústria de produtos farmacêuticos. Outra questão a ser levantada é a contaminação do meio ambiente por essa classe substâncias, pois após o uso pelo ser humano ocorre a eliminação natural de parte da concentração administrada, assim sendo liberadas nos esgotos e, posteriormente, contaminando os corpos d\'água, a fauna e flora local. Assim, foi proposto um métodos diferente para a degradação desses compostos, utilizando a eletrodos de difusão gasosa (EDG) capazes de gerar peróxido de hidrogênio in situ e em meio ácido, precursores dos radicais hidroxila, responsáveis pela degradação. Foram estudados EDG\'s não catalisados e catalisados, com diferentes porcentagens de ftalocianina de ferro II, com relação à quantidade de peróxido produzido, melhor potencial de produção e cinética do processo. Os resultados revelaram que a incorporação de 0,5% de Ft-Fe no eletrodo apresentou os melhores resultados. Esse eletrodo foi escolhido então para realizar as degradações dos antibióticos sulfametoxazol e trimetoprim. Na célula eletroquímica utilizou-se o processo Fenton, as reações ocorreram em uma faixa de potencial (-0,4 V ≤ E ≤ -1,4 V) e no reator foi utilizado um potencial fixo (-1,75 V) mas utilizando processos de Fenton e Foto-Fenton. As amostras degradadas foram avaliadas por técnicas analíticas de espectroscopia no ultravioleta (UV), cromatografia líquida de alta eficiência (HPLC) e teor de carbono orgânico total (TOC). Os resultados mostraram que, na célula eletroquímica, o melhor potencial de degradação foi de -1,1 V, com uma taxa de redução de 25,5% para o trimetoprim e 96,0% do sulfametoxazol e uma diminuição do teor de carbono orgânico total de 10,4%. Para o reator o melhor resultado foi obtido para o processo de Foto-Fenton onde houve uma redução de 16,9% do teor de carbono orgânico total e uma redução de 99,7% do sulfametoxazol e 11,3% do trimetoprim, em um potencial de -1,75 V. Considerando a formação de subprodutos foi elaborada uma rota de degradação com os possíveis compostos formados. / Currently the class of antibiotics is notable for the large consumption and also the risk to health when administered in error, this increase is due to the growing prominence of the pharmaceutical industry. Another issue to be addressed is the environmental contamination by substances that class, because after use by humans part of the concentration administered is naturally eliminated, thus being released into sewers and subsequently contaminating water bodies, the local fauna and flora. Thus, different methods has been proposed for the degradation of these compounds, using gas diffusion electrodes (GDE) capable of generating hydrogen peroxide in situ and in acid medium, precursors of hydroxyl radicals, responsible for degradation. We studied GDE\'s not catalyzed and catalyzed with different percentages of iron phthalocyanine II, with respect to the amount of peroxide produced better yield potential and kinetic process. The results revealed that the incorporation of 0.5% of Ft-Fe in the electrode showed the best results. This electrode was then chosen to perform the degradation of the antibiotic sulfamethoxazole and trimethoprim. In the electrochemical cell used in the Fenton process, the reactions occurred in a potential range (-0.4 V ≤ E ≤ -1.4 V) and in the reactor was used a fixed potential (-1.75 V) but using Fenton and photo-Fenton processes. Degraded samples were analyzed by analytical techniques, ultraviolet spectroscopy (UV), high performance liquid chromatography (HPLC) and total organic carbon content (TOC). The results showed that in the electrochemical cell, the best degradation potential was -1.1 V, with a reduction rate of 25.5% for trimethoprim and 96.0% for sulfamethoxazole and a decreased carbon content total of 10.4%. For the reactor the best result was obtained for the photo-Fenton process where there was a reduction of 16.9% of the total organic carbon content and a reduction of 99.7% of sulfamethoxazole and 11.3% of trimethoprim, in a potential of -1.75 V. Considering the formation of byproducts was drafted a route with the possible degradation compounds formed.

Du fait du coût élevé de certains matériaux adsorbants d’intérêt pour le traitement de la micropollution organique, l’étude a porté sur la régénération de matériaux adsorbants de type zéolithes hydrophobes et monolithe de carbone dans le cas de l’adsorption du bisphénol A et du diclofénac comme micropolluants réfractaires. Des procédés d’oxydation avancée impliquant des espèces radicalaires HO• (réaction de Fenton, électro-Fenton) et SO₄• – (activation de persulfate par voie thermique) ont été utilisés pour assurer la régénération des matériaux par désorption et dégradation oxydative des polluants fixés. La production de radicaux HO• au sein de la phase aqueuse circulant au niveau de l’adsorbant n’est pas suffisamment efficace pour sa régénération. Il a donc été envisagé de générer les radicaux au plus près des molécules adsorbées. Au cours de ce travail, une méthode sensible d’analyse par polarographie de H₂O₂ a été développée et validée pour le suivi des expériences avec les procédés mettant en jeu la réaction de Fenton. Pour différentes zéolithes, le catalyseur de la réaction de Fenton à base de fer a été incorporé préalablement dans la zéolithe. Pour le monolithe de carbone, les propriétés de conduction du matériau ont été mises à profit en l’utilisant comme cathode pour l’application du procédé électro-Fenton permettant de produire les radicaux HO• directement au sein du matériau. Cela a conduit à améliorer les performances de la régénération avec toutefois une diminution de son efficacité au cours de cycles successifs adsorption/régénération. / The elimination of organic micropollutants often requires the use of adsorption processes among the water treatments. The aim of our study is to regenerate two expensive materials (hydrophobic zeolites and carbon monoliths) to increase their life expectancy and decrease their investing cost. Two organic contaminants were targeted : diclofenac and bisphenol A, which are refractory pollutants. Advanced oxidation processes involve radical species, HO• (Fenton and electro-Fenton reactions) and SO₄• – (thermal activation of persulfate ion). These oxidants were used to decompose the adsorbed pollutants and thus regenerate the adsorbents. The HO• production, within the core of aqueous phase, did not reach satisfactory regeneration, and a loss of adsorption capacity was observed. Furthermore, during this study, a sensitive polarographic analytical method was developed and validated for the quantification of H₂O₂ in the aqueous phase. This method was used to follow in situ the Fenton reaction. The location of the catalyst in a closer vicinity of the adsorbed species was then optimized and the iron catalyst was impregnated in the host, prior to the adsorption, on different types of hydrophobic zeolites. Concerning carbon monolith, the electro-Fenton process was carried out using the material as the cathode thanks to its electrical conductivity. Consequently, HO• are produced in the porosity of monolith. This latter property enhanced the degradation of adsorbed solutes. The overall performances were increased compared to the homogeneous Fenton process. Nonetheless, a decrease of the adsorption capacities with adsorption-regeneration cycles was observed.

Healthcare facility wastewaters are a potentially important and under characterized source of pharmaceuticals and personal care products to the environment. In this study the composition and magnitude of pharmaceuticals and personal care products (PPCPs) released into a single municipality’s wastewater system from a hospital, a nursing care facility, an assisted living facility and an independent living facility are presented for 54 pharmaceuticals, 8 hormones and 31 Alkylphenol ethoxylates (APEOs). Chemical oxidation using molecular ozone and advanced oxidation processes (AOPs) (UV-hydrogen peroxide, Fenton’s Reagent, and Photo – Fenton’s Reagent) were screened and evaluated as potential treatment technologies for removal of APEOs in water and wastewater. In this research, APEOs were found to be dominant PPCP class out of 94 individual analytes measured, accounting for more than 65% of the total mass loading observed leaving the healthcare facility wastewater. Seventy one out of the total measured PPCPs were detected in wastewater from at least one of the facilities. Healthcare facility wastewater are the source of PPCPs to the environment; however, their contribution to the total magnitude of PPCPs in municipal wastewater and the surrounding environment will be determined by the relative flow contribution of wastewater released from the facility to the municipal sewer network. Molecular ozone and advanced oxidation processes were observed to remove APEOs from analyzed water matrices; however, understanding the product formation during the oxidation process is important before concluding a suitable treatment process. Molecular ozone reacted selectively with the double bond in the APEO while AOPs reaction was non selective oxidation. During the AOPs, OH· formation rate and scavenging rate constant of wastewater was found to be the factors governing the oxidation process. Thus, the research carried out informs a risk management decisions concerning the prevalence of PPCPs in the wastewater and use of oxidation systems as a treatment technologies for removal of PPCPs.