Substâncias tóxicas como o fenol e outros compostos aromáticos dificultam o tratamento de efluentes via digestores biológicos. Estes compostos tóxicos em altas concentrações são nocivos aos lodos biológicos, podendo inviabilizar por completo o tratamento. Nas últimas décadas, os Processos Oxidativos Avançados (POAs), como os processos Fenton e foto- Fenton, surgiram como alternativa para o tratamento de compostos tóxicos. Os POAs degradam os compostos orgânicos pela geração de compostos oxidantes fortes, como o radical hidroxila, a partir de reagentes como peróxido de hidrogênio. Os processos Fenton e foto-Fenton fazem uso de ferro (II), um catalisador relativamente barato, para catalisar a decomposição do peróxido de hidrogênio, reação denominada como reação de Fenton. Em virtude dos complexos mecanismos presentes nos processos Fenton e foto-Fenton, torna-se necessária uma compreensão da cinética do processo, que envolve reações térmicas e fotoquímicas, por meio de sua modelagem matemática fenomenológica. A modelagem da degradação do fenol via processos Fenton e foto-Fenton proposta por este trabalho começa pela estequiometria dos dois processos, que descreve as reações químicas, térmicas e fotoquímicas existentes. A partir destas, é possível desenvolver o modelo cinético dos processos Fenton e foto-Fenton, no qual se determina a velocidade com que estas reações ocorrem. O passo seguinte é o da modelagem hidráulica (ou de escoamento) dos reatores de processo Fenton e foto-Fenton, sendo que para o segundo processo, o modelo deve levar em conta a propagação da radiação por dentro de reator. Foram realizados 3 experimentos de degradação de fenol via processo Fenton para análise das variações das concentrações de fenol, catecol e hidroquinona. Os dados experimentais são comparados com resultados simulados com intuito do ajuste das constantes cinéticas do modelo. Com as constantes ajustadas, são realizadas comparações entre os processos Fenton e foto-Fenton para análise de suas eficiências. A partir dos modelos matemáticos dos reatores de processos Fenton e foto-Fenton, é desenvolvido um modelo de otimização baseado em superestrutura de redes de reatores para a síntese de uma planta de tratamento de efluentes contaminados com fenol. Objetivou-se a redução dos custos de capital, operação e depreciação desta planta, sujeitos às restrições de projeto e ao modelo da superestrutura, resultando em modelos de programação não-linear inteira mista. Foram geradas soluções ótimas para o tratamento de efluentes contaminados com fenol em redes de um, dois e três reatores de POAs. / Toxic substances such as phenol and other aromatic compounds make the wastewater treatment by biological (aerobic or anaerobic) digestors more difficult. These toxic compounds in high concentrations are harmful for the biological sludge and they may render the treatment impractical. In recent decades, Advanced Oxidative Processes (AOPs) appeared as an alternative for the treatment of toxic compounds. AOPs degrade the organic compounds by generating strong oxidizing compounds, such as the hydroxyl radical, from reactants such as hydrogen peroxide. The Fenton and photo-Fenton processes make use of iron (II), a relatively inexpensive catalyst, to catalyze the hydrogen peroxide decomposition, reaction known as the Fenton reaction. Because of the complex nature of the mechanisms that take place in the Fenton and photo-Fenton processes, the understanding of the process kinetics, which involves thermal and photochemical reactions, becomes necessary through its first-principle mathematical modeling. The modeling of phenol degradation by the Fenton and photo-Fenton processes proposed in this work starts with the stoichiometry of the two processes that enumerates the existing thermal and photochemical reactions. Furthermore, it is possible to develop the Fenton and photo- Fenton kinetic model, which determines the reaction rates. The next step is to model the hydraulic (or flow) behavior of the Fenton and photo-Fenton process reactor, whereas the model for the latter must consider how the radiation propagates inside the reactor. Three experiments of the phenol degradation by the Fenton process were carried out to analyze the concentration variation for phenol, catechol and hydroquinone. The experimental data are compared with simulated results aiming the estimation of the kinetic constants of the model. Using the adjusted constants, the Fenton and photo-Fenton processes were compared to analyze their efficiencies. From the mathematical models of the Fenton and photo-Fenton process reactors, an optimization model based on reactor network superstructure is developed for the synthesis of a phenol contaminated wastewater treatment plant. The objective is to minimize the plant capital, operation and depreciation costs, subject to design constraints and to the superstructure model, thus resulting in mixed integer nonlinear programming models. Optimal solutions were generated for the phenol contaminated wastewater treatment in networks with one, two and three AOP reactors.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-05-31T12:54:54Z No. of bitstreams: 2 Dissertação - Weberson de Oliveira Morais - 2015.pdf: 1625123 bytes, checksum: f4f86c2fdb7e73438d0f4555a6827285 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-05-31T12:56:10Z (GMT) No. of bitstreams: 2 Dissertação - Weberson de Oliveira Morais - 2015.pdf: 1625123 bytes, checksum: f4f86c2fdb7e73438d0f4555a6827285 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-05-31T12:56:10Z (GMT). No. of bitstreams: 2 Dissertação - Weberson de Oliveira Morais - 2015.pdf: 1625123 bytes, checksum: f4f86c2fdb7e73438d0f4555a6827285 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-09-30 / Advanced oxidation processes are consolidated technologies when it comes to treatment of industrial wastewater. Such processes are based on the generation of the hydroxyl radical (• HO), with high potential to oxidize organic matter (2,8eV). These, because they are poorly selective and highly reactive, oxidize the organic matter from promoting an increase in the biodegradable fraction to a possible complete mineralization of the contaminant in the wastewater. Among the advanced oxidation processes, the Fenton’s reagent stands out for its simplicity, low treatment time and low economic value. This reaction proceeds by catalytic decomposition of hydrogen peroxide (H2O2), in acid pH, by oxidizing Fe+2 to Fe+3 with the subsequent generation of the hydroxyl radical. In the Fenton’s reaction, some intermediate reactions give a unique characteristic to the process during the treatment which stand out hydrolysis of Fe+2 and Fe+3 forming a series of aqueous ferrous and ferric complexes which enable the occurrence of Process coagulation / flocculation with subsequent formation of sludge. The integration of these two technologies confers the treated wastewater a significant increase in contaminant removal, because, from this stage, the process of sedimentation, there is the drag of a large amount of non-degraded organic matter via chemical oxidation, in the form of sludge. In this work the application of integrated Fenton’s reaction to coagulation / flocculation in the treatment of cosmetic wastewater sunscreen lotion production line. The treatment was performed at Jar Test equipment with one liter volume: carried out rapid mixing at 300 rpm for 20 seconds after the addition of ferrous sulfate heptahydrate, subsequently slow mixing at 30 rpm for 6 minutes and 10 seconds after the addition of hydrogen peroxide. After this sequence, each test was allowed to rest on sedimentation for 60 minutes. The entire process took place at ambient temperature. At first the treatment was executed in a simulated wastewater from a sunscreen acquired in a cosmetics industry in the metropolitan area of Goiânia. After optimization of the concentration of 22,12 mgL-1 Fe+2, 500 mgL-1 H2O2 and pH 4.0, we observed a reduction of 82.56% in the chemical oxygen demand (COD) , 97.33% and 98.00% in turbidity in absorbance which indicated a high efficiency of the treatment in regard to an adjustment to CONAMA Resolution 430 2011. Other parameters were analyzed in order to obtain reliable information about the proposed treatment, and a reduction of 91.49% of Total Organic Carbon (TOC), 99.67% of oils and greases, 98.81% of total suspended solids (TSS), 73.05% of surfactants and 64.68 % of total phenols. The total treatment time was 226 minutes and 30 seconds. With these removal treatment with the actual wastewater was considered extremely efficient for a possible application of this methodology in the industrial segment, it should be observed that when applied in an isolated way, the advanced oxidation processes do not have good efficiency, however, in this study the treatment means Fenton’s reaction integrated technology coagulation / flocculation has a high capacity for a full-scale application in the cosmetic segment. / Os processos oxidativos avançados são tecnologias consolidadas em se tratando de tratamento de efluentes industriais. Tais processos são baseados na geração do radical hidroxila (•OH) que possui elevado potencial de oxidar a matéria orgânica (2,8eV). Estes, por serem pouco seletivos e altamente reativos, oxidam a matéria orgânica promovendo desde um aumento na fração biodegradável até uma possível mineralização total do contaminante presente no efluente. Dentre os processos oxidativos avançados, o reagente de Fenton se destaca pela sua simplicidade, baixo tempo de tratamento e baixo valor econômico. Esta reação se processa pela decomposição catalítica do peróxido de hidrogênio (H2O2), em meio ácido, através da oxidação de Fe+2 a Fe+3 com a posterior geração do radical hidroxila. Durante a reação de Fenton, algumas reações intermediárias dão ao processo uma particularidade ímpar durante o tratamento, das quais, se destacam a hidrólise dos íons Fe+2 e Fe+3 formando uma série de complexos aquo-ferrosos e férricos que possibilitam a ocorrência do processo de coagulação/floculação com a posterior formação de lodo. A integração destas duas tecnologias confere ao efluente tratado um aumento significativo na remoção de contaminantes, pois, a partir desta etapa, com o processo de sedimentação, ocorre o arraste de grande quantidade da matéria orgânica não degradada via oxidação química, na forma de lodo. Neste trabalho foi estudada a aplicação da reação de Fenton integrada à coagulação/floculação no tratamento de efluente cosmético da linha de produção de filtro solar. O tratamento foi realizado no equipamento JAR TEST com volume de um litro: Realizou-se a mistura rápida a 300 rpm por 20 segundos, logo após a adição de sulfato ferroso hepta-hidratado, posteriormente a mistura lenta, a 30 rpm por 6 minutos e 10 segundos com a adição de peróxido de hidrogênio. Após esta sequência, cada teste ficou em repouso para sedimentação por 60 minutos. Todo processo ocorreu em temperatura ambiente. Em um primeiro momento o tratamento foi realizado em um efluente simulado a partir de um filtro solar adquirido em uma indústria cosmética da região metropolitana de Goiânia. Após a otimização da concentração de 22,12 mgL-1 de Fe+2, 500 mgL-1 H2O2 e valor de pH 4,0, foi possível observar uma redução de 82,56% na Demanda Química de Oxigênio (DQO), 97,33% na turbidez e 98,00% na absorvância o que indicou uma elevada eficiência do tratamento no que diz respeito a uma adequação à resolução CONAMA 430 de 2011. Outros parâmetros foram analisados a fim de obter informações mais seguras a cerca do tratamento proposto, e com redução de 91,49% de Carbono Orgânico Total (COT), 99,67% de óleos de graxas, 98,81% de sólidos suspensos totais (SST), 73,05% de surfactantes e 64,68% de fenóis totais, a reação de Fenton foi considerada um processo de elevada eficiência no tratamento de efluente da linha de produção de filtro solar. Após a aplicação deste tratamento em efluente simulado, o próximo passo foi à aplicação da metodologia ao efluente cosmético real da linha de produção de filtro solar. Com o processo de otimização, a concentração “ótima” de Fe+2 e H2O2 foi de 110 mgL-1 e 700 mgL-1, respectivamente e um valor de pH 4,5. Nestas condições, as mesmas análises do efluente simulado foram realizadas e os valores de remoção foram 90,75% de Demanda Química de Oxigênio (DQO), 99,61% de turbidez, 98,24% de absorvância, 96,24% de Carbono Orgânico Total (COT), 99,26% de óleos e graxas, 97,36% de sólidos suspensos totais (SST), 73,12% de surfactantes e 81,85% de fenóis totais. O tempo total de tratamento foi de 226 minutos e 30 segundos. Com estas remoções o tratamento com o efluente real foi considerado de extrema eficiência para uma possível aplicação da metodologia no segmento industrial, cabe salientar que quando aplicados de maneira isolada, os processos oxidativos avançados não apresentam boa eficiência, no entanto, neste trabalho o tratamento via reação de Fenton integrado à tecnologia coagulação/floculação apresentou elevada capacidade para uma aplicação em escala real no segmento cosmético.

Made available in DSpace on 2017-07-10T18:08:00Z (GMT). No. of bitstreams: 1 Thyara Campos Martins.pdf: 1837547 bytes, checksum: 733e952ccfb67393e6688fdf9fec96e7 (MD5) Previous issue date: 2013-02-14 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this study is to evaluate the performance of Fenton-like process using steel wool trade as a source of metallic iron and ferrous ions in the treatment of textile effluent. Preliminary experiments were conducted to evaluate the efficiency of the Fenton-like degradation and mineralization of organic and inorganic pollutants. The experiments were conducted in laboratory scale reactors. The operational parameters of the reactor: H2O2 molar concentration of reactants and Fe0 were optimized based on the values of total organic carbon (TOC), chemical oxygen demand (COD), turbidity and discoloration from an experimental design Delineation Central Composite Rotational (DCCR) 22 quadruplicate with the center point and another 4 axial points. Obtained good representation of the experimental data verified by analysis of variance. The efficiency of the processes used in the treatment of textile effluent was evaluated based on the parameters: decreased levels of TOC, COD, color and turbidity, as well as analysis of the behavior of the concentrations of sulfate, nitrate, hydrogen peroxide, dissolved iron, ammonia and organic nitrogen and reduced absorbance in the lengths where 320 and 600 nm. The molar ratio of the highest efficiency for conventional Fenton process was 1:0,9:27,5 to their COT:Fe2+:H2O2. Under these conditions, the process decreased by 91.06% of the TOC parameter, whereas the COD was reduced by 94.51%, 99.02% of discoloration and 99.88% of reduced turbidity. The Fenton-like process showed greater reductions of the parameters studied when subjected to 1:1,7:27,5 molar ratio of the respective TOC:Fe0:H2O2; these conditions the process showed 92.88% reduction of TOC, 93.91% reduction of COD, 98.11% of discoloration and 98.87% reducing turbidity. Both procedures showed these results to a reaction time of 720 minutes. Using the continuous flow system for the FL and FC process, the system allowed an efficient degradation of the effluent at retention times of about 720 minutes. The processes presented similar efficiencies, which demonstrates that the Fenton-like process is an effective alternative for the treatment of textile effluents. Confirming the ability of steel wool as the source of metallic iron, capable of use in oxidation processes of degradation. / O objetivo deste trabalho é avaliar o desempenho do processo Fenton-like, utilizando lã de aço comercial como fonte de ferro metálico e íons ferrosos, no tratamento de efluente têxtil. Foram realizados experimentos preliminares para avaliar a eficiência do processo Fenton-like na mineralização e degradação dos poluentes orgânicos e inorgânicos. Os experimentos foram realizados em reatores de escala laboratorial. Os parâmetros operacionais dos reatores: concentração molar dos reagentes H2O2 e Fe0, foram otimizados baseados nos valores do carbono orgânico total (COT), demanda química de oxigênio (DQO), descoloração e turbidez a partir de um planejamento experimental Delineamento Composto Central Rotacional (DCCR) 22 com quadruplicata no ponto central e mais 4 pontos axiais. Obteve-se boa representação dos dados experimentais verificada pela análise de variância. A eficiência dos processos aplicados no tratamento do efluente têxtil foi avaliada baseada pelos parâmetros: redução dos valores do COT, DQO, cor e turbidez, além da análise do comportamento das concentrações de sulfato, nitrato, peróxido de hidrogênio, ferro dissolvido, nitrogênio orgânico e amoniacal e redução da absorvância nos comprimentos de onde de 320 e 600 nm. A razão molar que apresentou maior eficiência para o processo Fenton Convencional foi de 1:0,9:27,5 respectiva ao COT:Fe2+:H2O2. Nessas condições, o processo apresentou redução de 91,06% do parâmetro COT, enquanto que a DQO apresentou redução de 94,51%, 99,02% de descoloração e 99,88% de redução da turbidez. O processo Fenton-like apresentou maiores reduções dos parâmetros estudados, quando submetido à razão molar de 1:1,7:27,5 respectivo ao COT:Fe0:H2O2; nessas condições o processo apresentou 92,88% de redução do COT, 93,91% de redução de DQO, 98,11% de descoloração e 98,87% de redução de turbidez. Ambos os processos apresentaram estes resultados para um tempo de reação de 720 minutos. Utilizando o sistema de fluxo contínuo para os processos FC e FL, o sistema permitiu uma eficiente degradação do efluente, em tempos de retenção da ordem de 720 minutos. Os processos apresentaram eficiências similares, o que demonstra que o processo Fenton-like é uma alternativa eficiente no tratamento de efluente têxtil. Atestando a capacidade da lã de aço como fonte de ferro metálico, passível de utilização em processos oxidativos de degradação.

[pt] O presente trabalho avalia a utilização de dois diferentes tipos de POA, Fenton-Zero - processo Fenton utilizando ferro zero valente: Fe0/H2O2 - e UV/H2O2 para o tratamento de efluente de indústria de celulose tratado biologicamente. Os parâmetros observados foram DBO, DQO, COT, cor e ABS280nm (medida de compostos ligninícos). Os experimentos foram conduzidos em batelada, em escala de laboratório e utilizando efluente real de indústria de celulose tratado biologicamente. Para os testes com o processo Fenton Zero foram realizados experimentos de acordo com um planejamento fatorial 2 elevado a 3, investigando a influência das variáveis pH, dosagem de peróxido de hidrogênio e massa de ferro zero valente fornecida por volume de solução. Como fonte de ferro foi utilizada lã de aço comercial nas concentrações de 5,5 g/L, 6,5 g/L e 7,5 g/L. As concentrações iniciais de peróxido de hidrogênio estudadas foram de 456,9 mg/L, 913,7 mg/L e 1370,6 mg/L e os valores de pH variaram entre 5.5, 6.5 e 7.5. Foram obtidas médias de remoção de 57,1 por cento de DQO, 67,2 por cento de DBO, 90,5 por cento de Cor, 83,4 por cento de compostos lignínicos e 54 por cento de COT, além de 9,52 mg/L de DBO final e 60,1 mg/L de DQO final. Já os testes com o sistema UV/H2O2 foram conduzidos com o único objetivo de polimento do efluente para reuso pelo processo. Desta maneira, o pH utilizado foi o natural do efluente (7,5) e três doses de H2O2 foram aplicadas, 4,0 g/L, 5,0 g/L e 6,0 g/L estando estas em excesso. / [en] The present work evaluates the use of two different types of AOP: the Zero-Fenton - process using zero valent iron - and UV/H2O2 for the treatment of pulp mill wastewater biologically treated. The observed parameters were BOD, COD, TOC, color and ABS280nm (measure of lignin compounds). The experiments were conducted in batch, lab scale and with real wastewater from biological treatment of a cellulose plant in Brazil. For the Fenton process, experiments were carried out according to a factorial design 23 investigating the influence of the variables pH, hydrogen peroxide dosage and zero-valent iron mass supplied by solution volume. As iron source, commercial steel wool was used in the concentrations of 5.5 g / L, 6.5 g / L and 7.5 g / L. The concentrations of hydrogen peroxide studied were 456.9 mg / L, 913.7 mg / L and 1370.6 mg / L and pH values ranged from 5.5, 6.5 and 7.5. The average removal rate was 57.1 per cent COD, 67.2 per cent COD, 90.5 per cent Color, 83.4 per cent lignin compounds and 54 per cent TOC. Also 9,52 mg/L of final BOD and 60,1 mg/L of final COD. The trials with the UV/H2O2 system, on the other hand, were conducted with the sole objective of polishing the effluent for reuse in the process. The pH used was the effluent s natural (7.5) and three excess doses of H2O2 were applied.

Parmi les procédés avancés d'oxydation (AOPs), les procédés de type Fenton (réactif de Fenton: Fe2+/H2O2) et les procédés d'oxydation par le persulfate, sont décrits comme des procédés très performants. Le procédé Fenton est une voie prometteuse et attractive pour le traitement d'une large variété de composés organiques polluants, difficiles à traiter par les voies classiques de dépollution. Au cours du procédé Fenton, des radicaux hydroxyles, molécules à fort pouvoir oxydant capable de réagir avec pratiquement tous types de composés organiques et inorganiques, sont générés. De même, du fait de la structure similaire entre H2O2 et les ions peroxydisulfate, ces derniers peuvent se décomposer en radicaux sulfates (SO4-•), un autre type d'oxydant hautement réactif pouvant réagir avec les composés organiques. Cependant, les procédés Fenton et d'activation du peroxydisulfate classiques présentent plusieurs inconvénients. En effet, la solution doit être acidifiée avant la réaction, et des procédés complexes de purification / séparation sont nécessaires après réaction. Afin de contourner ces inconvénients, le développement de procédés de traitement hétérogènes est proposé pour le traitement de l'eau. Dans cette optique de développement de procédés économes, les oxydes de fer comme la magnétite sont proposés comme remplaçants des sels solubles de fer. Une utilisation de tels matériaux, à l'état solide, présente des avantages indéniables, dont la séparation aisée de l'espèce active après réaction par sédimentation ou filtration. Dans le cadre de ce travail de doctorat, différents types d'oxydes de fer, hématite ou magnétite, ont été synthétisés en milieu liquide ionique. La morphologie, les propriétés structurales, les rapports de surface FeII/FeIII, les surfaces spécifiques, les tailles de domaine cristallin, etc. ont été évaluées. Deux molécules différentes, la tétracycline (TC) et le phenol, couramment utilisées dans l'industrie chimique, ont été sélectionnées comme polluants modèles afin d'évaluer les performances des matériaux préparés pour leur élimination. Une partie importante du travail de doctorat a donc été l'étude des propriétés des matériaux pour l'élimination de polluants organiques par le procédé Fenton hétérogène. Les résultats montrent clairement que les principaux facteurs affectant les performances du procédé sont reliés aux propriétés de la phase active, du fait du caractère surfacique des réactions. La stabilité des systèmes catalytiques préparés est néanmoins une propriété cruciale également étudiée. Le manuscrit de doctorat met donc l'accent sur la conception de matériaux originaux destinés à une utilisation dans les procédés avancés d'oxydation dans l'eau. / Fenton reaction (Fenton reagent: (Fe2+/H2O2)) and persulfate oxidation process, as advanced oxidation processes, are powerful oxidations used world around. Fenton reaction has been evidenced to be a promising and attractive treatment method for the degradation of a wide variety of hazardous organic pollutants, which are difficult to be treated using traditional soft treatment technologies. During Fenton process, free hydroxyl radicals (HO•), strong oxidant molecules capable of reacting with practically all types of organic and inorganic compounds, are generated. In the meanwhile, due to the similar structure between H2O2 and peroxydisulfate ions, peroxydisulfate ions can be decomposed to sulfate radicals (SO4-•), another kind of highly active oxidant that can react with organic compounds. However, the classical Fenton or peroxydisulfate activation processes present some disadvantages. Indeed, the solution needed acidification before carrying out the reaction and complex separation processes have to be applied after reaction. To overcome these drawbacks, heterogeneous catalytic oxidation processes were introduced for wastewater treatment. In this line, magnetite was evidenced as potential substituent to soluble iron ions, and it offers significant advantages such as an easy separation after reaction since the active material can be easily recovered by sedimentation or filtration for further used. In this PhD work, iron oxides, hematite and magnetite, were synthesized using an ionic liquid mediated process. The morphology, structural properties, FeII/FeIII surface ratios, specific surface areas (SSA), mean particle diameters, site densities, etc. were evaluated. Two different model pollutants (tetracycline (TC) and phenol), which are widely used chemicals all over the world, were selected to evaluate the performance of the prepared active materials. A significant part of the PhD study was then on the study of heterogeneous Fenton-like reaction for phenol and TC degradation. Experiments showed that the main factors affecting the heterogeneous Fenton-like system are related to the heterogeneous active phase properties, due to the surface reaction nature occurring over iron oxide surface. However, stability of this active phase, with progressive dissolution under reaction, is also a real challenge. This PhD manuscript, focusing on the design of highly active materials for advanced oxidation processes (AOPs), is constituted of five experiment result parts.

La production ainsi que l'utilisation massive des produits chimiques pour divers usages, a résulté à leur introduction et accumulation dans l'environnement. Ces produits peuvent se transporter par différentes façons de leur source à des régions très lointaines de la planète, ce qui dépend de leur propriété physico-chimiques. Une quantité et variété importante de composés organiques sont utilisées dans l'agriculture comme pesticides, afin de protéger les cultures et augmenter les rendements. Les résidus de ces produits peuvent toujours se trouver dans les champs, puis sous l'effet des précipitations ils passent par lixiviation dans les fleuves et d'autres system aqueux. Les produits pharmaceutiques et les produits de soins personnels sont introduits dans l'environnement de façon continue par les eaux usés municipales. Ces substances manifestent, dans la plus part des cas, des effets perturbants sur les organismes vivants. Malgré leur concentration faible dans les eaux naturelles, le contact permanent des organismes aquatiques peut avoir des conséquences négatives telles que la modification du comportement sexuel observé chez les poissons d'eau douce. Dans le but de réduire ou éliminer la pollution chimique des eaux des nombreuses méthodes ont vu le jour, telles que: l'adsorption des polluants sur des adsorbants, la filtration membranaire, le traitement microbiologique, l'oxydation chimique et les procédés d'oxydation avancée. La plus part des méthodes utilisées dans les stations d'épuration des eaux ne détruisent pas efficacement les contaminants organiques. L'utilisation des méthodes physiques permet de les séparer de l'eau, ce qui nécessite des opérations supplémentaires pour leur élimination. Au contraire, les procédés d'oxydation avancée et en particulier les procédés électrochimiques d'oxydation avancée (méthodes développées récemment) se montrent plus efficace dans l'élimination des polluants toxiques et non-biodégradables, car ces procédés sont capables à conduire jusqu'à minéralisation totale de la matière organique. Le sujet de cette thèse repose donc sur l'application du procédé électro-Fenton qui est un procédé électrochimique d'oxydation avancée pour la destruction des contaminants organiques dans l'eau. Cette méthode fait appel aux radicaux hydroxyles (espèces très oxydantes et extrêmement réactives) pour l'élimination des polluants récalcitrants, qui sont produit in situ à travers le réactif du Fenton (H2O2 + Fe2+). Ce réactif est généré in situ électrochimiquement. . Dans ce procédé la nature du matériau de l'électrode a une importance cruciale. Ainsi nous avons étudié dans ce travail l'influence du matériel de l'anode et de la cathode sur l'efficacité du procédé électro-Fenton. Dans un premier temps nous avons étudié de manière systématique le pouvoir d'oxydation d'anode comme de différentes matériaux d'anodes tels que : BDD, Pt, DSA, PbO2, Feutre de carbone, Graphite et Fibre de carbone dans l'oxydation de l'antibiotique amoxicilline (AMX). Dans tous les cas une électrode d'acier inox a été utilisée comme cathode. La dégradation de AMX a été suivie par l'analyse CLHP alors que la minéralisation de ses solutions par l'analyseur du carbone organique totale (COT). Il s'est avéré que l'anode BDD a était l'anode la plus puissante pour l'oxydation de l'AMX tandis que l'anode DSA a présenté les performances les plus faibles. D'autre part, le feutre de carbone a présenté un comportement caractéristique; il était très efficace sur l'oxydation de l'AMX mais ces performances en minéralisation étaient médiocres. Dans l'étape suivante, quatre anodes (Pt, BDD, DSA and Feutre de carbone) ont été testées pour élucider leur influence sur l'efficacité du procédé électro-Fenton, en utilisant toujours une cathode de feutre de carbone. L'antibiotique sulfamethazine (SMT) a été choisi comme polluant modèle (...) / Permanent production and use of organic chemicals for many purposes has resulted in their introduction and accumulation in the environment. Depending on their physicochemical properties they can be transported by different ways from the source to very remote regions of the planet. Many organic chemicals are used in agriculture as pesticides for cultures protection or nutrient. Residues of these chemicals can always be found in fields, and under the effect of precipitations they leach and pass in streams and rivers. Pharmaceuticals and personal health care products and other house holding chemicals are continuously introduced in the environment through municipal wastewaters. These substances exhibit, in most of the cases, perturbation effects towards the living organisms, moreover the effect of many of them is not known yet. Despite their concentration in water is low, the exposure of organisms for long periods can lead to negative consequences, but these effects cannot be measured instantly. In order to reduce or avoid the pollution of water with chemicals many water treatment methods has been developed like adsorption of pollutants on adsorbents, membrane filtration, microbiological treatment, chemical oxidation with oxidizing agents and advanced oxidation processes. Most of the methods used in waste water treatment plants (WWTP) do not completely destroy the organic contaminants or they only separate the contaminants from water. Then they have to be deposed somewhere else remaining always a potential source of contamination. Advanced oxidation processes and in particular electrochemical advanced oxidation processes are methods developed later and are proven as more effective as they can completely oxidize the organic matter in water. The subject of this thesis is the use of electro-Fenton, an electrochemical advanced oxidation process for efficient destruction of organic pollutants in aqueous medium. In this method, organic pollutants are eliminated by H hydroxyl radicals (high oxidation power species) which are produced in situ through the Fenton's reagent (H2O2 + Fe2+) itself generated in the solution electrochemically and continuously. In this process, the electrode material is of fundamental importance in order to have an efficient process, so we have studied at large extent the influence of both cathode and anode material in this work. Firstly a systematic study on the oxidation capacity of the process of amoxicillin (AMX) as model pollutant with several anodes materials: BDD, Pt, DSA, PbO2 Carbon felt, Graphite and Carbon fibre was realised. In all cases a stainless steel electrode was used as cathode. The degradation of AMX was followed by HPLC analysis whereas the mineralization efficiency ot the process was measured by total organic carbon analyser (TOC). This revealed that BDD was the most efficient anode for AMX oxidation and DSA was the weakest one. Carbon felt showed a characteristic behaviour; it was very efficient on AMX oxidation but it could not transform AMX to CO2 and H2O. Afterwards four anodes were tested for their influence on electro-Fenton process efficiency namely Pt, BDD, DSA and Carbon felt, the cathode was always carbon felt. Sulfamethazine (SMT) was used as model pollutant. Apparent rate constants have given only moderate values of mineralization for currents lower than 100 mA. Here again the BDD anode was distinguished for its excellent mineralization capacity owing to the additional hydroxyl radicals and other oxidizing species introduced in the system. When electro-Fenton applied good degradation and mineralization results were obtained even with the DSA anode (...)

<p>Predmet izučavanja ove disertacije je ispitivanje mogućnosti primene homogenog, heterogenog i Fentonsličnog procesa u tretmanu obojenih otpadnih voda grafičke industrije.&nbsp; Kao Fenton katalizatori kori&scaron;ćeni su sintetisani gvožđe(III)-molibdat i nano nula valentno gvožđe, kao i komercijalni gvožđe(II)-sulfat. Istraživanja&nbsp; su sprovedena u četiri faze. U prvoj fazi&nbsp; je izvr&scaron;ena sinteza&nbsp; i karakterizacija&nbsp; Fenton&nbsp; katalizatora, pri čemu su ustanovljene njihove osnovne morfolo&scaron;ke karakteristike. Nano nula valentno gvožđe je sintetisano iz ekstrakta&nbsp; li&scaron;ća hrasta, dok je&nbsp; gvožđe(III)-molibdat sintetisan putem tzv. vlažnog hemijskog postupka. U drugoj fazi je&nbsp; izvr&scaron;ena optimizacija Fenton procesa u tretmanu sintetičkih rastvora grafičkih&nbsp; boja primenom nove statističke&nbsp; metode,&nbsp;<em> definitive screening design</em>.&nbsp; U&nbsp; cilju postizanja&nbsp; maksimalnog stepena obezbojavanja i mineralizacije tretiranog uzorka&nbsp; ispitan&nbsp; je&nbsp; uticaj&nbsp; sledećih&nbsp; procesnih parametara: inicijalne koncentracije boje, koncentracije gvožđa, pH vrednosti i koncentracije vodonik-peroksida. Nakon ustanovljenih optimalnih uslova i izvr&scaron;ene verifikacije predloženog optimuma, sproveden je tretman realnog efluenta.&nbsp; Stepen mineralizacije&nbsp; tretiranog&nbsp; efluenta&nbsp; ustanovljen&nbsp; je&nbsp; na&nbsp; osnovu&nbsp; vrednosti&nbsp; sadržaja&nbsp; ukupnog&nbsp; organskog&nbsp; ugljenika&nbsp; i&nbsp; hemijske&nbsp; potro&scaron;nje kiseonika.&nbsp; U cilju razumevanja mehanizma degradacije grafičkih boja u Fenton procesu, kao i identifikacije prirode&nbsp; degradacionih&nbsp; produkata,&nbsp; izvr&scaron;ena&nbsp; je&nbsp; kvalitativna&nbsp; gasno-hromatografska/maseno&nbsp; spektrometrijska analiza. Kinetika obezbojavanja realnog&nbsp; efluenta&nbsp; najbolje&nbsp; je opisana primenom&nbsp; Behnajady&nbsp; -&nbsp; Modirshahla&nbsp; -Ghanbary&nbsp; modela,&nbsp; koji&nbsp; defini&scaron;e&nbsp; inicijanu&nbsp; brzinu&nbsp; i&nbsp; oksidacioni&nbsp; kapacitet&nbsp; posmatranog&nbsp; procesa.&nbsp; Rezultati&nbsp; su ukazali&nbsp; na&nbsp; moguću&nbsp; primenu&nbsp; Fenton&nbsp; procesa&nbsp; u&nbsp; tretmanu&nbsp; CMYK&nbsp; boja&nbsp; usled&nbsp; postizanja&nbsp; visokih&nbsp; efikasnosti obezbojavanja i mineralizacije tretiranih efluenata. Nedostatak primenjene metode se ogleda u činjenici da je većina&nbsp; uzoraka&nbsp; okarakterisana&nbsp; kao&nbsp; visoko&nbsp; toksična,&nbsp; a&nbsp; ujedno&nbsp; i&nbsp; izrazito&nbsp; kisela,&nbsp; budući&nbsp; da&nbsp; je&nbsp; ustanovljena optimalna&nbsp; pH&nbsp; vrednost&nbsp; Fenton&nbsp; tretmana&nbsp; 2&nbsp; -&nbsp; 3.&nbsp; Stoga&nbsp; je&nbsp; u&nbsp; okviru&nbsp; treće&nbsp; faze&nbsp; istraživanja&nbsp; primenjen&nbsp; dodatni tretman&nbsp; realnog&nbsp; efluenta,&nbsp; adsorpcija&nbsp; na&nbsp; aktivnom&nbsp; uglju&nbsp; sintetisanom&nbsp; iz&nbsp; ko&scaron;tica&nbsp; divlje&nbsp; &scaron;ljive.&nbsp; Adsorpcioni tretman&nbsp; je rezultovao smanjenjem&nbsp; toksičnosti&nbsp; kod&nbsp; svih tretiranih uzoraka, koji&nbsp; se&nbsp; karakteri&scaron;u&nbsp; kao nisko do umereno toksični, te je sa tog aspekta moguće njihovo bezbedno ispu&scaron;tanje u recipijent. Ujedno je ustanovljena i povećana mineralizacija uzoraka, kao posledica degradacije jedinjenja koja su inicijalno doprinela povećanoj toksičnosti. U četvrtoj fazi rada primenjena je metoda ocenjivanja životnog ciklusa sinteze Fenton katalizatora. Rezultati LCA su utvrdili da sinteza heterogenog Fenton katalizatora, gvožđe(III)-molibdata, ostvaruje najveće opterećenje&nbsp; životne&nbsp; sredine,&nbsp; dok&nbsp; bi&nbsp; se&nbsp; proces&nbsp; sinteze&nbsp; nano&nbsp; nula&nbsp; valentnog&nbsp; gvožđa&nbsp; mogao&nbsp; unaprediti modifikovanjem ekstrakcione faze uz kori&scaron;ćenje alternativnih materijala i obnovljivih izvora energije. Značaj&nbsp; predstavljenih rezultata se ogleda u činjenici da su uzorci obojenih otpadnih voda grafičke industrije prvi put podvrgnuti Fenton tretmanu koji je rezultovao visokim stepenom efikasnosti.</p> / <p>The subject of this thesis is&nbsp; exploring the possibility of homogeneous, heterogeneous and Fenton-like process application in the treatment of dye wastewater in printing industry. Synthesized iron(III)-molybdate and nano zero valent iron, as well as commercial iron(II)-sulfate were used as a Fenton catalyst. The research was carried out in four&nbsp; phases.&nbsp; In&nbsp; the&nbsp; first&nbsp; phase,&nbsp; the&nbsp; catalyst&nbsp; synthesis&nbsp; and&nbsp; their&nbsp; characterization&nbsp; were&nbsp; performed,&nbsp; whereby&nbsp; the morphological characteristics were established. Nano zero valent iron was synthesized from&nbsp; oak leaf extract&nbsp; and iron(III)-molybdate was synthesized by wet chemical process. In the second phase, the optimization of Fenton process was performed within the treatment of synthetic printing dye solution using a new statistical method, a definitive screening design. In order to achieve maximum decolorization and mineralization of the treated sample, the influence of&nbsp; following&nbsp; process parameters was conducted: initial dye concentration, iron concentration, pH value&nbsp; and hydrogen peroxide concentration.&nbsp; The treatment of printing effluent was performed&nbsp; after&nbsp; establishing optimal&nbsp; conditions&nbsp; and&nbsp; verifying&nbsp; the&nbsp; proposed&nbsp; optimum&nbsp; values.&nbsp; Mineralization&nbsp; degree&nbsp; of&nbsp; treated&nbsp; effluent&nbsp; was determined based on the results of total organic carbon and chemical oxygen demand. In order to understand the dye&nbsp; degradation&nbsp; mechanism&nbsp; in&nbsp; Fenton&nbsp; process,&nbsp; as&nbsp; well&nbsp; as&nbsp; to&nbsp; identify&nbsp; degradation&nbsp; products,&nbsp; a&nbsp; qualitative&nbsp; gaschromatographic/mass spectrometric analysis was carried out. The&nbsp; kinetic studies of the printing effluent were best described by using the Behnajady- Modirshahla-Ghanbary model, which defines the initial speed and oxidation capacity of the process. The results indicated the possible application of the Fenton process in the treatment of CMYK dyes due to the high decolorization and mineralization efficiency of treated effluent. Disadvantage of the applied method is reflected in the fact that most of the samples are characterized as highly toxic and,&nbsp; at the same time, extremely acidic since the optimum pH value of Fenton treatment is 2 - 3. Therefore, in the third phase of the study, adsorption process on functionalized biochar prepared from wild plum kernels was applied on real printing effluent.&nbsp; Adsorption&nbsp; treatment&nbsp; resulted&nbsp; in&nbsp; toxicity&nbsp; reduction&nbsp; in&nbsp; all&nbsp; treated&nbsp; samples,&nbsp; characterized&nbsp; as&nbsp; low&nbsp; to moderately toxic. Therefore, from this aspect, treated effluent can be safely released into the recipient. At the same time, increased mineralization of the samples was established as a result of the compounds degradation that initially contributed to high toxicity. In the fourth phase, a life cycle assessment method of Fenton catalyst was applied. The results of the LCA indicated that the synthesis of the heterogeneous Fenton catalyst, iron(III) molybdate, achieved the highest environmental burden, while the synthesis of nano zero valent iron could be improved by modifying the extraction phase using alternative materials and renewable energy sources.&nbsp; The significance of the obtained results is high decolorization efficiency achieved by Fenton treatment of printing dye wastewater,&nbsp; which was used for the first time.</p>

Dans cette étude nous avons cherché à évaluer les paramètres et les mécanismes gouvernant la réactivité des catalyseurs à base de cérium lors de la dégradation des colorants textiles, seuls ou en mélange binaire, dans le cadre du procédé Fenton/photo-Fenton. Dans ce but, 5 séries de catalyseurs à base de cérium ont été testées pour déterminer les effets respectifs : (i) de la surface spécifique de CeO2 commercial (SBET = 11, 101,5 ; 148 ; 235 et 284 m2/g), (ii) du dopage au zirconium (oxydes mixtes CexZr1-xO2 avec différentes teneurs en cérium (x = 0 ; 0,2 ; 0,5 ; 0,8 ; 1)), (iii) d’un traitement de sulfatation de CexZr1-xO2 par H2SO4, et (iv) de l’imprégnation de CeO2 par différents métaux (M = Ba, Bi, La, V et Mo). Les propriétés texturales, structurales et chimiques des catalyseurs à base de cérium étudiés ont été dans la plupart des cas caractérisées par porosimétrie à l’azote, DRX, Raman, XPS, FTIR/ATR, DR-UV-Vis et ATG. Les cinétiques de décoloration et de minéralisation de l’Orange II en présence de CeO2 et H2O2 dépendent fortement de la surface spécifique des catalyseurs ainsi que des paramètres opératoires (présence d’irradiation UV-Vis, pH, température, concentration initiale en catalyseur et en H2O2). Par comparaison avec les colorants pris séparément, l’adsorption compétitive de l’Orange II et de l’Acide Vert 25 sur les mêmes sites d’adsorption à pH = 3 réduit les taux de dégradation des deux colorants en mélange. En revanche, l’association de l’Orange et du Vert de Malachite en paires d’ion, permet d’améliorer la cinétique apparente de dégradation du Vert de Malachite d’un facteur 5. Dans ce cas, la réaction de Fenton et la coagulation-floculation contribuent simultanément à l’élimination de deux colorants de charge opposée en présence du système CeO2/H2O2. De plus, les performances des oxydes mixtes Ce-Zr dans le procédé Fenton hétérogène sont étroitement liées à leurs caractéristiques texturales, structurales et chimiques. Les analyses effectuées ont permis de vérifier les phases cristallines des oxydes mixtes de révéler la formation de solutions solides. Le traitement de sulfatation conduit à la diminution de la surface spécifique et l’augmentation de la taille des cristallites des oxydes riches en Ce. La dissolution de CeO2 lors de sulfatation suivie par formation d’une phase amorphe Ce(SO4)2 à la surface du catalyseur a été mise en évidence. Le traitement de sulfatation ainsi que le dopage au Zr permettent d’augmenter la densité de surface en sites réduits Ce(III). Les études en spectroscopies DR-UV-Vis, FTIR/ATR et Raman relatives à l’adsorption et l’activation d’H2O2 par les oxydes mixtes ont permis de mettre en évidence l’existence d’espèces Ce-peroxo de surface, comme intermédiaires pour générer les radicaux hydroxyles. La détermination quantitative de ces espèces par TPD-MS s’est avérée utile pour mieux comprendre les performances catalytiques des oxydes mixtes modifiés ou non. La concentration en Ce de surface, la densité de défauts Ce(III) (augmenté par dopage et le traitement de sulfatation) et la surface spécifique semblent être à cet égard parmi les paramètres les plus influents sur l’activité. L’imprégnation de CeO2 par différents métaux n’a pas montré un impact positif sur la réactivité de ce matériau en procédé Fenton. Un mécanisme général d’activation d’H2O2 a été proposé sur la base des résultats expérimentaux obtenus et la littérature. De point de vue mécanistique, les analyses spectroscopiques par ATR/FTIR et UV-Vis montrent que l’adsorption de l’Orange II à la surface du catalyseur est fortement dépendante du pH du milieu et se fait par des interactions électrostatiques. Le mécanisme de dégradation de l’Orange II, en phase liquide et à la surface du catalyseur, a été étudié par différentes techniques (DR-UV-VIS et ATR/IR, HPLC et GC/MS) / In this work, the parameters and mechanisms governing the reactivity of cerium based materials towards the degradation of textile dyes, taken separately or in binary mixture, in Fenton/photo-Fenton process have been investigated. For this purpose, five sets of catalysts were performed in order to determine the respective effects of : (i) the specific surface area of commercial CeO2 (SBET = 11, 101,5 ; 148 ; 235 and 284 m2/g); (ii) the zirconia doping ((CexZr1-xO2 with different Ce content (x = 0 ; 0,2 ; 0,5 ; 0,8 ; 1)); (iii) the treatment with H2SO4 ; and (iv) the impregnation of different metals in CeO2 (M = Ba, Bi, La, V and Mo). The textural, structural and chemical properties of the studied ceria-based materials were systematically characterized by nitrogen porosimetry, Raman, XRD, XPS, ATR/FTIR, DR-UV-Vis and TGA. Discoloration and mineralization kinetics of Orange II dye in presence of CeO2/H2O2 system are strongly related to the surface area of catalysts and other parameters (UV-Vis irradiation, pH, temperature, concentration of catalyst and H2O2). The presence of another dye with similar (Acid Green 25) or opposite charge (Malachite Green) can also influence the discoloration kinetics of Orange II. Comparing with single dye solutions, the degradation efficiency of both Orange II and Acid Green 25 were reduced in the mixture due to the competitive adsorption of both anionic dyes onto the same surface Ce sites. However, the discoloration of Malachite Green was enhanced in the presence of Orange II due to the simultaneous contribution of both coagulation/flocculation and Fenton-like process. It is suggested that a Malachite Green ion is electrostatically attracted by an Orange II ion at pH = 3. In addition, the performance of the mixed oxides in the heterogeneous Fenton process is strongly related to their textural, structural and chemical properties. Briefly, characterizations by XRD and Raman spectroscopy indicate that these nanosized mixed oxides can be considered as good quality solid solutions and possess structural properties consistent with the known phase diagram of CexZ1-xO2. The sulfation treatment mostly affects the Ce rich catalysts by increasing the crystallite size and lowering the specific surface area. The dissolution of ceria during sulfation followed by formation of Ce(SO4)2 amorphous phase on catalyst surface was investigated by UV-Vis and TGA analysis. Sulfation treatment as well as doping ceria with Zr increases the amount of reduced sites Ce (III) and defect sites.DR-UV-Vis, FTIR/ATR and Raman spectroscopic studies for adsorption and activation of H2O2 on mixed oxides show the formation of surface Ce-peroxo species as intermediate to generate hydroxyl radicals. The relative amounts of these species on the mixed oxides and/or not modified was indirectly determined using TPD-MS, giving rather good indication about the performances of catalysts towards the degradation of dye. The concentration of surface Ce, the density of defects Ce(III) sites (increased by doping and sulfation treatment) and the surface area appear to be among the most important parameters affecting the catalytic activity. Impregnation of ceria with different metals did not show a positive effect on the reactivity of this material in Fenton process. A possible mechanism for the activation of H2O2 was discussed in details according to all the experimental results and to the literature. From a mechanistic viewpoint, it is shown using FTIR/ATR and liquid UV-Vis spectroscopic measurements that the adsorption of the anionic dye is highly pH-dependent and proceeds via electrostatic interactions with surface metal centers. A possible pathway for Orange degradation is proposed on the basis of qualitative and quantitative detection of intermediate compounds, in liquid phase and on catalyst surface, using various techniques (FTIR/ATR, DR-UV-VIS, HPLC and GC/MS)

Ce travail de thèse concerne le développement de catalyseurs Fe/Faujasite afin de dégrader un cocktail de micropolluants provenant d’une eau réelle de rivière dans la Meurthe (France) avec le procédé photo-Fenton hétérogène. Les micropolluants étudiés appartiennent à 4 grandes familles : des principes actifs pharmaceutiques, des produits de soins cosmétiques, des perturbateurs endocriniens, et des composés perfluorés. Pour la première fois, dans cette thèse, la dégradation d’un mélange de 21 micropolluants à l’état de traces (2 – 80 ng/L) provenant d’une réelle eau de rivière non-dopée a été effectuée. Cependant, le fait de travailler avec des concentrations très faibles en polluants reste un challenge notamment en ce qui concerne les aspects de chimie analytiques. Ce travail de thèse est donc divisé en deux grandes parties. Dans un premier temps, il a été nécessaire de trouver la meilleure eau réelle contenant un nombre élevé de micropolluants de différentes natures à des concentrations de l’ordre de quelques ng/L mais inférieures à 100 ng/L. Pour cela différentes campagnes de prélèvement ont été effectuées dans les deux principales rivières de la région Lorraine, la Meurthe et la Moselle, en différents lieux et différentes périodes de l’année. L’eau provenant du site de Moulin Noir a été choisie. Dans une deuxième partie, nous avons développé des catalyseurs fer/Faujasite pour pouvoir tester leur efficacité pour la dégradation des micropolluants provenant du site de Moulin Noir par le procédé photo-Fenton hétérogène. Dans une étape intermédiaire, l’optimisation des paramètres opératoires du procédé photo-Fenton avec nos catalyseurs a été effectuée en utilisant deux macropolluants modèles, phénol et diclofenac / Twenty one 21 micropollutants including pharmaceuticals, personal cares product, endocrine disruptors and perfluorinated compounds presenting at ng/L in the real water of Meurthe river, were successfully quantified and removed using heterogeneous photo-Fenton process. To achieve this goal, an analytical-catalytic methodology was developed and the work steps were performed linked together in a cycle-like manner. The use of the sensitive and efficient multi-residual SPE-LC-MS/MS analytical method allowed us to analyze and quantify the mixture of micropollutants present in a complex matrix during 3 periods of the year with different weather conditions, from 5 sampling sites. Results showed that the highest concentrations of most of the present micropollutants are observed in October at ng/L, Moulin Noir sampling site found to contain the largest number and type of these pollutants, the WWTP was not efficient in the removal of the micropollutants present in water and the drinking water used from tab was totally safe from micropollutants. The calculation of the fluxes and estimation of the mass balance at the rivers confluence confirmed the good precision and reliability of our measurement methodology, and specify the most suitable site for water to be taken from to be used in the removal tests which was Moulin Noir. Having the appropriate water sample, an efficient iron impregnated Faujasite catalyst was developed and used in a photo-Fenton process for the micropollutant removal tests. After characterization and optimization of the different experimental factors using the 2 model macropollutants, phenol and diclofenac, the real tests were performed on real water samples from Moulin Noir. The results demonstrated the good efficiency of the photo-Fenton process with the cocktail of 21 micropollutants. Except for sulfamethoxazole and PFOA, the concentrations of all the other micro-contaminants became lower than the limit of quantification of the LC-MS/MS after 30 minutes or 6 hours of photo-Fenton treatment depending on their initial concentrations under the effect of both adsorption and Fenton mechanisms. Comparing the photo-Fenton process to heterogeneous photocatalytic degradation over TiO2, Faster micropollutants removal occurred with the zeolite

M. Tech. (Department of Chemistry, Faculty of Applied and Computer Sciences), Vaal University of Technology. / Organic water pollutants such as dyes are difficult to biodegrade. In this study Fenton, photo-Fenton and photocatalysis were used to degrade methylene blue dye in the presence of copper oxide catalysts. The copper oxide catalysts were prepared with a precipitation reduction method. The effect of different preparation parameters on the catalyst properties and catalytic activity were investigated. The reducing agents, ascorbic acid (ASC, C6H8O6), hydrazine (N2H4), sodium boron hydride (NaBH4) and glucose (C₆H₁₂O₆) could be used to obtain the desired Cu2O phase. ASC, N2H4 and NaBH4 were able to reduce copper (II) to copper (I) at room temperature whereas glucose required a higher reduction temperature. Stoichiometric amounts of the reducing agents ASC, N2H4 and glucose and double the stoichiometric amount of NaBH4 were required to obtain Cu2O. A further increase in the amounts of NaBH4 and N2H4 resulted in the formation of copper metal (Cu (0)). High amounts of ASC did not over-reduce the copper. ASC also functioned as capping molecule and anti-oxidant preventing the oxidation of the Cu2O to CuO in air after preparation. Hydrazine was thus not able to protect the Cu2O against oxidation. The SEM results showed that an increase in the amount of the precipitating agent, NaOH, resulted in an increase in the particle sizes. The particle shapes changed from spherical to cubic when a high amount of NaOH was used with hydrazine as reducing agent. Smaller particle sizes were obtained when CuCl2 was used instead of CuSO4 and Cu(NO3)2. Larger crystallites formed when the preparation temperature was increased from room temperature to 100°C with glucose as reducing agent. TEM and XRD analyses showed that the micro-particles seen in SEM analyses are made up of nano-particles. The catalysts were not active for photocatalysis which may be explained by the oxidation of these nano-particles to form the photocatalytic inactive CuO. The catalysts were shown to be active for Fenton and photo-Fenton degradation. The addition of graphene and activated carbon to the Cu2O catalysts were detrimental to the catalytic activity. The percentage degradation of methylene blue by the Fenton reaction increased with an increase in the BET surface area from 1.5 m2/g to 10 m2/g and a further increase in the surface area resulted in a decrease in the percentage degradation. A direct correlation between the Fenton catalytic activity and the pore size were found which indicate that the reaction was mass transfer limited.