A indústria farmacêutica acarreta a geração de uma quantidade significante de resíduos potencialmente poluidores. Ao serem lançados em corpos d\'água, os efluentes das indústrias farmacêuticas provocam desequilíbrio no ambiente, por transportarem compostos de difícil degradação. A ocorrência desses resíduos no ambiente pode favorecer a resistência de microrganismos frente a esses fármacos, além de causar problemas de ordem toxicológica a determinados organismos vivos. No intuito de minimizar os impactos causados pelos despejos dos efluentes desta atividade industrial, torna-se necessário estudar tratamentos alternativos para degradação de tais resíduos. Esta pesquisa teve como proposta avaliar um Processo Oxidativo Avançado: Ozonição Catalítica Homogênea em presença de íons Fe2+ como técnica para tratamento de efluente veterinário, para tanto foram estudados três diferentes reatores em sistema contínuo. Na primeira etapa do estudo, foi definido o modelo de reator mais adequado para o tratamento desse efluente farmacêutico veterinário. Na segunda etapa do estudo, utilizou-se um planejamento fatorial fracionado 24-1 para otimizar as variáveis do processo: pH, concentração de Fe2+ g/L, potência do ozonizador (vazão mássica de O3) e vazão de saída do efluente do reator. A eficiência do tratamento foi avaliada por meio da redução de Carbono Orgânico Total (COT) (%). Este estudo mostrou que a condição experimental na qual se observou a maior porcentagem de redução de COT (46,14%) ocorreu quando se combinou pH 4,0, [Fe2+] de 0,5 g/L, vazão de saída do reator de 1,23 L/h e potência do ozonizador de 56W. A avaliação estatística desse planejamento apontou para uma nova configuração experimental na qual se obteve 55,24% de redução de COT, degradação do ativo Fenbendazol de 71,24% e degradação do ativo Triclabendazol de 95,68%. Essa nova configuração combinou pH 4,0, [Fe2+] de 0,1g/L, vazão de saída do reator de 1,85 L/h e potência de 56W. / The pharmaceutical industry generates a significant amount of potentially polluting waste. When released into stream, the pharmaceutical effluents cause imbalance in the environment, transporting compounds are difficult to degrade. The occurrence of these residues in the environment can improve the microbial resistance of these drugs and cause toxicological implication of certain organisms. In order to minimize the impacts caused by discharges of effluents of this industrial activity, it is necessary to study alternative treatments for degradation of the waste. The purpose of this work was to evaluate proposed system using continuous reactors as one treatment technique Advanced Oxidative Process: Catalytic Homogeneous Ozonization with Fe2+. In the first stage of the study, the reactor model more suitable for treatment of this veterinary pharmaceutical effluent. In the second stage of the study, used a design factorial 24-1to optimize the variables of the process: pH, concentration of Fe2+ g/L, ozoniser power and output flow reactor. The efficiency of the treatment was evaluated by the reduction of Total Organic Carbon rate (TOC) (%). This study showed that the experimental condition in which it was observed the highest percentage of TOC reduction (46.14%) occurred when combined pH 4.0, [Fe 2 +] 0.5 g / L, the output flow reactor 1.23 L / h and ozoniser power of 56W. The statistical evaluation of this planning pointed to a new experimental setup in which we obtained 55.24% reduction of TOC, degradation of drug Fenbendazole 71.24% and degradation of 95.68% drug Triclabendazole. This new configuration combined pH 4.0, [Fe 2 +] of 0.1 g / L, output flow reactor of 1.85 L / h and ozoniser power of 56W.

Durante anos, o lixo da cidade de Guaratinguetá foi aterrado e o seu produto recalcitrante não passou por nenhum tratamento físico ou mesmo químico, percolando diretamente sob o aterro. Mesmo tendo sido desativado e transformado em Parque Ecológico, o material depositado no local ao longo dos anos, continuará a ser decomposto por microrganismos e continuará a ser produzido o lixiviado como fonte de poluição ambiental. Inicialmente, fez-se a caracterização do chorume \"in natura\", demonstrando-se como fonte de matéria orgânica recalcitrante, com massa molar característica de macromoléculas (5,58 kDa e polidispersidade de 1,16), DBO não determinável pela recalcitrância molecular e/ou pela ação tóxica e DQO característica de lixiviado estabilizado (1.013 mg L-1). A fração inorgânica total, dada pela quantidade de sólidos fixos, foi de 3.670 mg L-1, valor esse 3,6 vezes maior que a fração orgânica. O estudo de tratamento do chorume, por ozonização catalítica homogênea foi desenvolvido, principalmente, pelo uso seqüencial de dois arranjos ortogonais de Taguchi, sendo o primeiro, matriz L16, para estudo exploratório dos fatores mais importantes na redução percentual da DQO. Os fatores estudados foram vazão de ozônio, concentração dos íons Fe2+, Fe3+, Zn2+, Mn2+, Ni2+ e Cr3+, pH do meio reacional e presença/ausência de fonte de radiação UV (254 nm). Dentre os metais de transição, os íons Fe2+ e Fe3+ demonstraram-se como mais viáveis como catalisadores na geração de radicais livres hidroxilas devido à sua significância estatística (p = 0,005), e por terem maior tolerância ao descarte no meio ambiente (menor toxicidade) frente aos demais íons. Com a utilização do arranjo ortogonal L8 de Taguchi, foi possível atingir degradação máxima de DQO da ordem de 50 %. A melhor configuração dos fatores, visando aumentar o percentual de redução da DQO foi: vazão de ozônio igual a 5 L h-1 (589,9 mg h-1 O3), concentração de íon de íon ferroso igual a 10 mg L-1, concentração de íon férrico igual a 5 mg L-1 e pH 5. / During many years, the garbage of Guaratinguetá city was landfilled and its recalcitrant product was not submitted to any physical or chemical treatment, leaching directly through the area. After deactivating and transforming the landfill into an Ecological Park, the material deposited in the place by the past years, will continue being decomposed by microorganisms and will continue producing the leached one as a mean of environment pollution. Initially, the leachate \"in natura\" was characterized, demonstrating itself as a source of recalcitrant organic substance with a higher molecular size characteristic of 5,58 kDa and polidispersity of 1,16 and stabilized effluent (not determinable DBO due to molecular recalcitrance and/or toxicity and DQO of 1,013 mg L-1). The total inorganic fraction, given by the amount of total fixed solids was 3,670 mg L-1, which means 3,6 times bigger than the organic fraction. The study of leachate treatment by homogeneous catalytic ozonation was given, mainly, for the sequential use of two Taguchi\'s orthogonal arrangements, being the first, L16 design, for exploratory studies of the most important factors in the percentual reduction of DQO. The factors studied were the ozone outflow, the Fe2+, Fe3+, Zn2+, Mn2+, Ni2+ and Cr3+ ions concentration, the reaction medium pH and the presence/absence of UV radiation source UV (254 nm). Amongst the transition metals, Fe2+ and Fe3+ ions have demonstrated to be as more viable as free hydroxyl radicals catalyst due to its statistics significance (p = 0,005) and also because they have a greater tolerance to the environment discarding (less toxicity) compared to the other ions. The use of L8 Taguchi\'s orthogonal arrays gives the possibility to reach 50 % maximum COD depletion. The best factors configuration, using COD percentage reduction as experimental design response was: 5 L h-1 (589,9 mg h-1 O3) ozone outflow, 10 mg L-1 ferrous concentration, 5 mg L-1 ferric ion concentration and pH 5.

Iron oxide nanoparticles (IONPs) have been widely studied for a variety of applications, from biomedical applications (e.g., cell separation, drug delivery, contrast agent for magnetic resonance imaging and magnetically mediated energy delivery for cancer treatment) to environmental remediations (e.g., heavy metal removal and organic pollutants degradation). It has been demonstrated that IONPs can induce the production of reactive oxygen species (ROS) via Fenton/Haber-Weiss reactions which has been shown to be one of the key underlying mechanisms of nanoparticles toxicity. This inherent toxicity of nanoparticles has been shown to enhance the efficacy of traditional cancer therapies such as chemotherapy and radiation. In addition, the generation of ROS induced by IONPs has been also studied as advanced oxidation processes (AOP) for wastewater treatment. Recent research has also shown that exposure to an alternating magnetic field can significantly enhance the generation of ROS induced by IONPs. Moreover, the coatings of IONPs play an important role on the surface reactivity of nanoparticles since it can prevent the generation of ROS via Fenton chemistries at the surface of the nanoparticles. In this work, co-precipitated IONPs were functionalized with small molecules including citric acid, sodium phosphate, amino silane and dopamine. The impact of coating on surface reactivity of the as-synthesized particles was studied using methylene blue dye degradation assay under AMF exposure. With the coatings of these small molecules, the IONPs induced ROS generation was significantly decreased because of the dense surface coverage. To study the effect of polymeric coatings, a degradable poly (beta amino ester) (PBAE) polymer coating was synthesized with dopamine as an anchor to bind to nanoparticles. The surface reactivity of the particles was expected to be recovered once the polymer coating was degraded. Furthermore, the impact of non-degradable PEG-based polymer coating on surface reactivity via ROS generation was also investigated using methylene blue decolorization assay with the presence of AMF. The retention of surface reactivity of PEG-based polymer coated IONPs shows promise for cancer treatment. The application of IONPs as heterogeneous catalyst for organic contaminant degradation was investigated. Bisphenol A (BPA) was used as a model compound, and Fenton reactions were induced by IONPs with the presence of hydrogen peroxide and hydroxylamine as well as alternating magnetic field exposure. The kinetics of BPA degradation under water bath and AMF exposure at 37oC was also studied, and the results showed potential applications of IONPs for organic pollutants remediation.

Esta tesis doctoral está dirigida a la investigación y desarrollo de Procesos de Oxidación Avanzada (POAs), los cuales basan su capacidad en la generación in-situ de radicales hidroxilo (OH·), especie capaz de oxidar muchos compuestos orgánicos. Esta propiedad es aprovechada para conseguir la completa mineralización de los contaminantes o su degradación en sustancias más fácilmente biodegradables.Se plantean dos grandes objetivos:1) Contribuir al conocimiento científico a través del análisis y modelado del proceso UV/H2O2 aplicado a la degradación y mineralización de fenol. Para ello, se ha realizado una planificación experimental dirigida a estudiar la influencia de las variables de operación sobre parámetros globales del proceso, como el contenido total de materia orgánica o la toxicidad.2) Desarrollar una alternativa eficaz para la eliminación de materia orgánica de corrientes residuales de escasa biodegradabilidad mediante la aplicación de POAs. Se ha seleccionado el tratamiento de lixiviados de vertedero de residuos sólidos urbanos (RSU) como caso de estudio y se ha realizado un análisis comparativo de los procesos Fenton y foto-Fenton. Los experimentos se han realizado tanto a escala de laboratorio como a escala de planta piloto. / The aim of this thesis is the research and development of Advanced Oxidation Processes (AOPs). AOPs are based on the in-situ generation of hydroxyl radicals (OH·). These radicals are able to oxidize many organic compounds with high oxidation rates but in a non-selective way. This is useful to achieve the complete mineralization of the pollutants or its degradation into more easily biodegradable compounds.Two main objectives have been pursued in this thesis:1) To contribute to the scientific knowledge of the UV/H2O2 process through its analysis and modelling. Phenol degradation has been selected as a case of study. An experimental planning was established to study the influence of process variables on parameters such as total organic matter concentration and ecotoxicity.2) Research on new alternative treatments for suitable organic matter removal from recalcitrant waste effluents by AOPs. As study case, the leachate remediation from a municipal solid wastes landfill was selected. Fenton and photo-Fenton processes were compared and the operational conditions to achieve the maximum organic matter reduction and colour removal have been determined. Both laboratory scale and pilot plant experiments were carried out.

Treatment of textile wastewaters containing dye materials using the conventional methods based on biological treatment is not possible. In order to overcome this problem, ozonation based on the oxidation of organic pollutants with ozone gas dissolved in aqueous phase have been studied widely. Catalytic ozonation and advanced oxidation processes (AOP) are also used in order to increase the efficiency of sole ozonation In this work, catalytic ozonation processes in the presence of Copper Sulfide (CuS) powder and a synthesized catalyst by the impregnation of iron on alumina (Fe/Al2O3) were studied separately in the treatment of dye solutions, namely Remazol Brilliant Blue-R (RBBR) and Reactive Black-5 (RB-5). Besides catalytic ozonation runs, ozonation parameters and ozonation mechanism were also studied and a model was developed for the semi-batch ozonation. Both catalysts increased the oxidation of side products measured by the decrease in the amount of total organic carbon (TOC) in the treated dye solutions. Dye removal rates were also enhanced in the treatment of RB-5 dye solutions while no significant effect was observed on dye removal rates of RBBR solutions. TOC removals above 90% were observed in the catalytic ozonation using CuS for both of the dye solutions at pH =10 having initial dye concentration of 100 mg/L. The most significant effect of the catalyst addition was observed at pH = 3 where the TOC removals of non-catalytic ozonation were the lowest. CuS addition increased percent TOC removal at the end of the reaction period of 80 min by 123% in the treatment of 100 mg/L RBBR solution, and by 65% in the treatment of 100 mg/L RB-5 solution at pH = 3. On the other hand, addition of Fe/Al2O3 catalyst increased TOC removal of 100 mg/L RB-5 solution by 52 % at pH = 3. In addition, volumetric mass transfer coefficients (kLa) of ozone in the absence and in the presence of a chemical reaction between dye and ozone were estimated from modeling. A correlation for the enhancement factor of ozone absorbed into dye solutions in terms of initial dye concentration was obtained and reported.

Emerging contaminants are defined as synthetic or naturally occurring chemicals or microorganisms that are not currently regulated but have the potential to enter the environment and cause adverse ecological and/or human health effects. With recent development in analytical techniques, emerging contaminants have been detected in wastewater, source water, and finished drinking water. These environmental occurrence data have raised public concern about the fate and ecological impacts of such compounds. Concerns regarding emerging contaminants and the many chemicals that are in use or production necessitate a task to assess their potential health effects and removal efficiency during water treatment. Advanced oxidation processes (AOPs) are attractive and promising technologies for emerging contaminant control due to its capability of mineralizing organic compound via reactions with highly active hydroxyl radicals. However, the nonselective reactivity of hydroxyl radicals and the radical chain reactions make AOPs mechanistically complex processes. In addition, the diversity and complexity of the structure of a large number of emerging contaminants make it difficult and expensive to study the degradation pathways of each contaminant and the fate of the intermediates and byproducts. The intermediates and byproducts that are produced may pose potential effects to human and aquatic ecosystems. Consequently, there is a need to develop first-principle based mechanistic models that can enumerate reaction pathway, calculate concentrations of the byproducts, and estimate their human effects for both water treatment and reuse practices. This dissertation develops methods to predict reaction rate constants for elementary reactions that are identified by a previously developed computer-based reaction pathway generator. Many intermediates and byproducts that are experimentally identified for HO* induced reactions with emerging contaminants include common lower molecular weight organic compounds on the basis of several carbons. These lower carbon intermediates and byproducts also react with HO* at relatively smaller reaction rate constants (i.e., k < 109 M-1s-1) and may significantly affect overall performance of AOPs. In addition, the structures of emerging contaminants with various functional groups are too complicated to model. As a consequence, the rate constant predictors are established based on the conventional organic compounds as an initial approch. A group contribution method (GCM) predicts the aqueous phase hydroxyl radical reaction rate constants for compounds with a wide range of functional groups. The GCM is a first comprehensive tool to predict aqueous phase hydroxyl radical reaction rate constants for reactions that include hydrogen-atom abstraction from a C-H bond and/or a O-H bond by hydroxyl radical, hydroxyl radical addition to a C=C unsaturated bond in alkenes and aromatic compounds, and hydroxyl radical interaction with sulfur-, nitrogen-, or phosphorus-atom-containing compounds. The GCM shows predictability; factor of difference of 2 from literature-reported experimental values. The GCM successfully predicts the hydroxyl radical reaction rate constants for a limited number of emerging contaminants. Linear free energy relationships (LFERs) bridge a kinetic property with a thermochemical property. The LFERs is a new proof-of-concept approach for Ab initio reaction rate constants predictors. The kinetic property represents literature-reported and our experimentally obtained hydroxyl radical reaction rate constants for neutral and ionized compounds. The thermochemical property represents quantum mechanically calculated aqueous phase free energy of activation. Various Ab initio quantum mechanical methods and solvation models are explored to calculate the aqueous phase free energy of activation of reactantas and transition states. The quantum mechanically calculcated aqueous phase free energies of activation are within the acceptable range when compared to those that are obtained from the experiments. These approaches may be applied to other reaction mechanisms to establish a library of rate constant predictions for the mechanistic modeling of AOPs. The predicted kinetic information enables one to identify important pathways of AOP mechanisms that are initiated by hydroxyl radical, and can be used to calculate concentration profiles of parent compounds, intermediates and byproducts. The mechanistic model guides the design of experiments that are used to examine the reaction mechanisms of important intermediates and byproducts and the application of AOPs to real fields.

Wastewaters from textile industry contain organic dyes, which cannot be easily treated by biological methods. Therefore, pretreatment by an advanced oxidation process (AOP) is needed in order to produce more readily biodegradable compounds and to remove color and chemical oxygen demand (COD) simultaneously. In this research, ozone (O3) is combined with hydrogen peroxide (H2O2) for the advanced oxidation of an azo dye solution, namely aqueous solution of Acid Red 151, which is called as &ldquo / Peroxone process&rdquo / . The aim of the study is to enhance the ozonation efficiency in treating the waste dye solution. The effects of pH, initial dye and initial ozone concentrations and the concentration ratio of initial H2O2 to initial O3 on color and COD removals were investigated. Also, the kinetics of O3-dye reaction in the presence of H2O2 was approximately determined. As a result of the experimental study, it was seen that an increase in the initial dye concentration at a constant pH and initial ozone concentration did not change the COD % removal significantly, from a statistical analysis of the data. The results obtained at pH values of 2.5 and 7 gave higher oxidation efficiencies in terms of color and COD removals compared to those at pH of 10. The best initial molar ratio of H2O2 to O3 was found to be 0.5, which yielded highest treatment efficiency for each pH value studied. The results of the excess dye experiments suggest that the ozonation of Acid Red 151 follows an average first order reaction with respect to ozone at pH=2.5 and pH=7 whereas it is around 0.56 at pH=10. By Initial Rate Method, the orders with respect to individual reactants of O3 and dye were determined as one, the total order of the reaction being two for all the studied pH. As a conclusion, a further study of the peroxone process at a pH of 10 can be recommended to determine the reaction kinetics and mechanism at this pH, where radicals play an important role.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The assessment of biomarkers of reactions involving reactive oxygen species have the potential not only to determine the extent of oxidative damage, but also to predict the effectiveness of therapeutic strategies aimed at reducing or preventing the damage promoted by oxidative stress. Recently, it has been described and characterized a new class of compounds formed in consequence of oxidative stress, designated as advanced oxidation protein products (AOPP). The accumulation of AOPP was first described in patients with chronic renal failure undergoing hemodialysis and was subsequently found in diabetes, atherosclerosis, obesity and acute renal failure. Previous studies have identified AOPP as a new marker of oxidative damage to proteins and a new class of inflammatory mediators, providing arange of effects at both the cellular and systemic levels. Although the mechanism of action by which AOPP act is not fully understood, it is known that these products activate respiratory burst in phagocytes, including neutrophils and monocytes, through the activation of enzymes present in these cells. Furthermore, it has been demonstrated that AOPP may promot these effects (pro-oxidants and pro-inflammatory) at several cell types such as endothelial and kidney cells via activation of a signaling cascade, and in some aspects of this cascade AOPP effects is very similar to effects caused by advanced glycation end products (AGEs). In this context, the evaluation of the antioxidant activity of compounds in vitro models involving the formation of AOPP may present special interest. Among these compounds, N-acetylcysteine (NAC) and Fructose-1 ,6-bisphosphate (FBP) may be promising substances for this purpose. The NAC is a sulfhydryl donor group very similar to the amino acid cysteine and FBP is a highly energetic intermediate metabolite of glycolysis. Thus, the aim of this study was to determine the effects of FBP and NAC, as well as the synergistic effect of both treatments on the formation of AOPP in vitro. For this purpose, purified human albumin was incubated with various concentrations of hypochlorous acid (HOCl) (1, 2 and 4 mM) to produce AOPP in vitro, which was named albumin-advanced oxidation protein products (albumin-AOPP). In this context, both FBP as NAC were able to inhibit the formation of AOPP concentration-dependent manner, with FBP 20mg/mL and NAC 1mg/mL were responsible for the inhibition of 64% and 85% respectively. Furthermore, the synergistic effect promoted by the association of both compounds was more effective ininhibiting the formation of AOPP. Therefore, FBP and NAC may be promising candidates to mitigate or neutralize the pro-inflammatory and pro-oxidant triggered by AOPP. / A avaliação de biomarcadores das reações que envolvem as espécies reativas de oxigênio têm potencial não apenas de determinar a extensão do dano oxidativo, mas também de predizer a eficiência das estratégias terapêuticas destinadas a reduzir ou prevenir os danos promovidos pelo estresse oxidativo. Recentemente, foi descrita e caracterizada uma nova classe de compostos formados em consequência do estresse oxidativo, designada como produtos proteicos de oxidação avançada (AOPP). O acúmulo de AOPP foi primeiramente descrito em pacientes com insuficiência renal crônica submetidos à hemodiálise e, posteriormente, verificou-se que este marcador está envolvido em várias condições patológicas, incluindo diabetes, aterosclerose, obesidade e insuficiência renal aguda. Estudos prévios têm identificado AOPP como um novo marcador de dano oxidativo a proteínas e uma nova classe de mediadores inflamatórios, promovendo uma série de efeitos tanto a nível celular quanto a nível sistêmico. Embora o mecanismo de ação pelo qual os AOPP agem não está totalmente esclarecido, sabe-se que estes produtos ativam o burst respiratório em fagócitos, incluindo neutrófilos e monócitos, através da ativação de complexos enzimáticos presentes nestas células. Além disso, tem sido demonstrado que os AOPP também podem promover efeitos deletéreis (pró-oxidantes e pró-inflamatórios) a vários tipos celulares, como células renais e endoteliais, através da ativação de uma cascata de sinalização, sendo em alguns aspectos desta cascata muito semelhante aos efeitos promovidos pelos produtos finais de glicação avançada (AGEs). Neste contexto, a avaliação da atividade antioxidante e antiinflamaória de compostos em modelos in vitro envolvendo a formação de AOPP pode apresentar especial interesse. Dentre esses compostos, a N-acetilcisteína (NAC) e a Frutose- 1,6-bisfosfato (FBP) podem ser substâncias promissoras para esta finalidade. A NAC é um doador de grupo sulfidrila muito semelhante ao aminoácido cisteína e a FBP é um açúcar bifosforilado e um metabólito intermediário altamente energético da glicólise. Assim, o principal objetivo deste estudo foi determinar o efeito da FBP e da NAC, bem como o efeito sinérgico de ambas, sobre a formação de AOPP in vitro. Para isso, a albumina purificada humana foi incubada com várias concentrações de ácido hipocloroso (HOCl) (1, 2 e 4 mM) para produzir AOPP in vitro, a qual foi denominada de albumina-produtos proteicos de oxidação avançada (albumina-AOPP). Neste contexto, tanto FBP quanto NAC foram capazes de inibir a formação de AOPP de maneira concentração-dependente, sendo que FBP 20 mg/mL e NAC 1mg/mL foram responsáveis pela inibição de 64% e 85% respectivamente. Além disso, o efeito sinérgico promovido pela associação de ambos os compostos foi maisefetivo em inibir a formação de AOPP quando comparado com o efetio promovido pelos compostos isoladamente. Portanto, FBP e NAC podem ser candidatos promissores para amenizar ou neutralizar os efeitos pró-inflamatórios e pró-oxidantes desencadeados pelos AOPP.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Due to the problems presented with the use of photo-Fenton homogeneous system, for the decomposition of recalcitrant organic compounds, several studies have been conducted in order to replace it with heterogeneous processes. The heterogeneous reaction of photo-Fenton catalysts using iron oxide base (Fe2O3) is viable and reputable to overcome the problems presented by the homogeneous system. However, when used pure Fe2O3 has low efficiency due to the large size of the agglomerates formed, so deposition techniques on substrates used are seeking to reduce the size of the iron oxide agglomerates. Thus this study aimed to evaluate the efficiency of iron oxide nanoparticle supported on zeolite ZSM-5 mesoporous in removing organic pollutants contained in wastewater using photo-Fenton reaction system. The synthesis of zeolites ZSM-5, which served as a support, was performed using nucleating gel as driver structure and different amounts of carbon nanoparticles as mesoporosity agent. On the particles of hierarchical zeolites ZSM-5 were deposited iron oxide nanoparticles (Fe2O3). Supporters and materials after impregnation were characterized by diffraction of X-ray (DRX), scanning electron microscopy (SEM) and analysis of the adsorption / desorption of nitrogen (BET). The evaluation of different catalysts was carried out in photo-Fenton system employing different conditions reaction. From the characterization using x-ray diffraction, it was found that the only crystalline phase was formed from ZSM-5 with high crystallinity, which was adversely affected with increasing carbon content in the gel nanoparticles of crystallization. In the analysis of the BET was found that the formation of type IV isotherms, indicating the presence of mesoporosity in the ZSM-5 zeolites. It was found that with increasing content of carbon nanoparticles in the reaction medium resulted in an increase in the average size of the mesoporous formed. In the catalytic evaluation in the photo-Fenton reaction it was found that under the same reaction conditions, the iron oxide supported on hierarchical zeolite ZSM-5 showed higher activity for decomposition of dyes than pure iron oxide. It was also found that, the higher the degree of mesoporosity of support of iron oxide supported higher activity. The higher activity of supported iron oxide was attributed to the synergistic effect with the ZSM-5 zeolite, which has polar character, making the dye concentration in the catalyst system surface is high, providing conditions for the smooth progress of the reaction. / Devido aos problemas apresentados com a utilização do sistema foto-Fenton homogêneo, para a decomposição de compostos orgânicos recalcitrantes, diversos estudos tem sido realizados com a finalidade de substituí-lo por processos heterogêneos. A reação heterogênea de foto-Fenton empregando catalisadores a base de óxido de ferro (Fe2O3) é alternativa viável e bem conceituada para superar os problemas apresentados pelo sistema homogêneo. No entanto, o Fe2O3 quando utilizado puro em suspensão apresenta baixa efetividade devido ao grande tamanho dos aglomerados formados, fazendo com que técnicas de deposição sobre suportes sejam utilizadas buscando reduzir o tamanho dos aglomerados de óxido de ferro. Desta forma, este estudo objetivou avaliar a eficiência do óxido de ferro nanoparticulado suportado sobre zeólitas ZSM-5 mesoporosas na remoção de poluentes orgânicos contidos em efluentes aquosos empregando sistema foto-Fenton de reação. A síntese das zeólitas ZSM-5, que serviram de suporte, foi realizada utilizando gel nucleante como direcionador de estrutura e diferentes teores de nanopartículas de carbono como agente de mesoporosidade. Sobre as partículas das zeólitas ZSM-5 hierárquicas, foram depositadas nanopartículas de óxido de ferro (Fe2O3). Os suportes e os materiais após impregnação foram caracterizados por difração de raios-X (DRX), microscopia eletrônica de varredura (MEV) e análise de adsorção/dessorção de nitrogênio (BET). A avaliação dos diferentes catalisadores foi realizada em sistema foto-Fenton empregando diferentes condições de reação. Da caracterização por difração de raios-X constatou-se que a única fase cristalina formada foi da zeólita ZSM-5 com elevado grau de cristalinidade, que foi afetada de forma negativa com a elevação do teor de nanopartículas de carbono no gel de cristalização. Na análise de BET constatou-se a formação de isotermas do tipo IV, indicando que a presença de mesoporosidade nas zeólitas ZSM-5. Constatou-se que com a elevação do teor de nanopartículas de carbono no meio reacional acarretou em aumento no tamanho médio dos mesoporosos formados. Na avaliação catalítica na reação de foto-Fenton constatou-se que, nas mesmas condições de reação, o óxido de ferro suportado sobre as zeólitas ZSM-5 hierárquicas apresentou maior atividade para decomposição de corantes que o óxido de ferro puro em suspensão. Também se constatou que, quanto mais elevado o grau de mesoporosidade do suporte maior a atividade do óxido de ferro suportado. A maior atividade do óxido de ferro suportado foi atribuído ao efeito sinérgico com a zeólita ZSM-5, que possui caráter polar, fazendo com que a concentração do corante na superfície do sistema catalítico seja elevado, propiciando condições para o bom andamento da reação.

Les papiers récupérés sont de plus en plus utilisés pour fabriquer du papier recyclé de haute blancheur. La ligne de recyclage inclut entre autres les opérations de désencrage et de blanchiment, le peroxyde d’hydrogène (H2O2) étant le réactif blanchissant le plus utilisé en milieu alcalin (stade P). Son efficacité est toutefois limitée car il est peu ou moyennement réactif sur les fonctions azoïques des colorants papetiers. L’objectif de cette étude était donc d’améliorer l’élimination des colorants azoïques lors d’un stade P.L'amélioration du stade P utilisé en délignification des pâtes chimiques a fait l’objet de nombreuses études. En particulier, l’activation ou la catalyse de H2O2 par des complexes cuivre(II)-phénanthroline (Cu-Phen) présentant des résultats très intéressants, des essais de blanchiment de pâtes désencrées et colorées ont été entrepris. Le système H2O2/Cu-Phen s’est également révélé efficace en décoloration, mais le mécanisme n’avait alors pas été étudié.L’objectif de ce travail était donc de déterminer dans quel cas et pourquoi le complexe cuivre(II)-phénanthroline était capable d’améliorer la décoloration de fibres cellulosiques colorées. Trois questions intermédiaires se sont posées : (1) quel effet Cu-Phen a-t-il sur le colorant isolé? (2) la décoloration d’une pâte de fibres colorées par H2O2 est-elle améliorée par Cu-Phen? (3) par quel mécanisme la décoloration est-elle rendue plus efficace?Le travail a donc été organisé en trois études : (1) caractérisation des colorants sélectionnés et du complexe en l’absence d’oxydant et examen des interactions entre les deux, (2) étude et optimisation paramétrique de H2O2/Cu-Phen pour la décoloration de pâtes colorées, (3) étude du mécanisme d’oxydation en milieu aqueux, en l’absence et en présence de cellulose.Ce travail s’est appuyé sur de nombreuses techniques analytiques (spectroscopies RMN, FTIR, UV-vis et RPE ; ESI-MS) et des calculs de spéciation. Il a prouvé que le complexe Cu-Phen en présence de H2O2 améliorait la décoloration de colorants azoïques, avec ou sans fibres cellulosiques. Il a été mis en évidence que la phénanthroline agissait comme un stabilisant permettant d’ajuster la solubilité, la stabilité et le potentiel d’oxydo-réduction du cuivre(II), mais qu’elle n’était pas indispensable. De plus, le pH du milieu est également un paramètre clé, jouant à la fois sur l’activité du complexe et sur ses interactions avec le substrat. Le substrat (colorant mais aussi cellulose) s’est trouvé fortement dégradé par ce système H2O2/Cu-Phen. Les résultats corroborent l’hypothèse de l’oxydation du substrat par les radicaux hydroxyles issus de la décomposition de H2O2, plutôt que par H2O2 lui-même, ce mécanisme étant l’une des étapes d’un cycle catalytique.La recherche menée et les résultats obtenus sont applicables non seulement à l’amélioration du blanchiment des pâtes désencrées, mais aussi au traitement d’effluents colorés dans les industries du papier et du textile. / Today, recovered papers are reused for the manufacture of bright paper after deinking and fiber bleaching, which generally starts with an alkaline hydrogen peroxide stage (H2O2). However, the efficiency of H2O2 is often limited due to its low reactivity on the azo groups of paper dyes contained in recovered papers. The goal of this study was to improve the removal of these azo dyes by H2O2.The improvement of H2O2 bleaching has been studied thoroughly in the context of chemical pulp delignification. In particular, the activation or catalysis of H2O2 by copper(II)-phenanthroline complexes (Cu-Phen) was found to be very effective. This inspired a preliminary bleaching study on deinked pulp and dyed pulp, and resulted in significant improvement of dye removal, which gave birth to our project.The purpose of this work was to determine to what extent copper(II)-phenanthroline could improve the hydrogen peroxide color-stripping of dyed cellulosic fibers, and how. To answer this question, three intermediate issues were addressed: (1) does Cu-Phen alone have an effect on the dye? (2) does Cu-Phen improve the color-stripping of a dyed pulp by H2O2? (3) how does the H2O2/Cu-Phen system enhance the dye-color-stripping efficiency?This work was thus divided into three studies: (1) the selected dyes and the complex were characterized in the absence of any oxidant and the interactions between the two were examined, (2) the H2O2/Cu-Phen system was applied on two dyed pulps to assess their color-stripping potential and to attempt to optimize it, and (3) the oxidation mechanism was investigated via trials in aqueous solution, with and without cellulose.Using several analytical techniques (NMR, FTIR, UV-vis and EPR spectroscopy; ESI-MS) and speciation calculations, this work proved that the Cu-Phen complex enhanced H2O2 for the color-stripping of azo dyes, with and without fibers. It also provided evidence that phenanthroline acted as a stabilizer to adjust the solubility, stability and redox potential of copper(II), but may not be indispensable. The substrate (dyes but also cellulose) was strongly degraded by the H2O2/Cu-Phen system. The results of the mechanistic study supported the hypothesis of substrate oxidation by radicals produced via decomposition of H2O2 rather than by hydrogen peroxide itself. This mechanism, strongly dependent on the pH, is probably part of a catalytic cycle.Finally, along with further research proposed based on our conclusions, this thesis should contribute to the improvement of deinked pulp bleaching as well as wastewater treatment in the pulp and textile industries.