O processo de liquefação hidrotermal (HTL) pode converter diversos tipos de biomassa em óleo bruto. Além do produto principal, é gerado um efluente (PHWW) com elevada carga orgânica, quantidades altas de nutrientes e compostos tóxicos. Para lidar com este tipo efluente tem-se sugerido a combinação de tratamentos físico-químicos e biológicos. O objetivo deste estudo foi avaliar a aplicação de processos oxidativos (por H2O2 e fotocatálise com TiO2) e digestão anaeróbia no tratamento do efluente da liquefação hidrotermal de Spirulina. Inicialmente caracterizou-se o efluente em termos de carga orgânica, nutrientes e compostos nitrogenados cíclicos (CNC). Posteriormente, avaliou-se a concentração de oxidante e o tempo de reação no processo de oxidação com H2O2. O tratamento fotocatalítico foi então avaliada no tratamento do efluente em questão, isoladamente, em sequência e combinada ao processo de oxidação por ação de H2O2. Finalmente combinaram-se os processos de oxidação por ação de H2O2 e digestão anaeróbia no tratamento de efluente de PHWW. O efluente da liquefação hidrotermal de Spirulina apresentou elevada carga orgânica, pH alcalino e concentrações altas de nutrientes (nitrogênio e fósforo). Verificou-se também a presença de CNC como pirazinas, δ-valerolactama, caprolactama e butirolactama. A aplicação do processo oxidativo por H2O2 no tratamento de PHWW apresentou efeitos positivos, principalmente para a descoloração que atingiu 93,8 %. A eficiência máxima de remoção de DQO foi de 15,3%. Foi percebida também redução nas concentrações dos CNC. A eficiência do processo de oxidação avançada por fotocatálise e H2O2 foi maior do que obtida quando estes processos foram aplicados separadamente. A aplicação dos processos combinados apresentou eficiência de remoção de cor e DQO semelhante às obtidas quando os processos foram aplicados em sequência, propiciando economia de tempo de reação. Por fim, verificou-se que a digestão anaeróbia do efluente pré-tratado com H2O2 apresentou maior produção de CH4 e remoção de matéria orgânica quando comparada com a digestão anaeróbia que o efluente in natura. Assim, conclui-se a utlização de processos oxidativos avançados ou a combinação da oxidação por H2O2 com a digestão anaeróbia são alternativas promissoras para o tratamento da PHWW. / The hydrothermal liquefaction process (HTL) can convert various types of biomass into bio-crude oil. In addition to the main product, wastewater (PHWW) is generated with high organic content, high amounts of nutrients and toxic compounds. To cope with this type of wastewater the combination of physicochemical and biological treatments has been suggested. The aim of this study was to evaluate the application of oxidative processes (using H2O2 and photocatalysis with TiO2) and anaerobic digestion in the treatment of hydrothermal liquefaction of Spirulina wastewater. Firstly, PHWW was characterized in terms of organic matter, nutrients and nitrogen heterocyclic compounds (CNC) concentrations. Secondly, the oxidant concentration and the reaction time in the oxidation process using H2O2 was evaluated. Photocatalytic treatment was then tested isolated, in sequence and combinated with the oxidation processo using H2O2. Finally, oxidation with H2O2 and anaerobic digestion were combinated and evaluated. The PHWW showed high organic load, alkaline pH and high concentrations of nutrients (nitrogen and phosphorus). The presence of CNC as pyrazines, δ-valerolactam, caprolactam and butyrolactam was also verified. The application of the oxidative process using H2O2 showed positive effects mainly for color removal, which reached 93.8%. The maximum efficiency of COD removal was 15.3%. Reduction in CNC concentrations was also observed . The efficiency of the advanced oxidation process (by combining photocatalysis and H2O2) was greater than that obtained when these processes were applied separately. The application of the combined process presented color and COD removal efficiencies similar to those obtained when the processes were applied in sequence, allowing reaction time savings. Finally, the anaerobic digestion of pre-treated (with H2O2) PHWW showed a greater CH4 production and higher organic matter removal, compared to anaerobic digestion of in natura PHWW. Thus it is possible to conclude that the utlization of advanced oxidation processes or the combination of oxidation with H2O2 and anaerobic digestion are promising alternatives for the treatment of PHWW.

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

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

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

O efluente lácteo é o resíduo obtido no beneficiamento do leite e seus derivados, sendo considerado um passivo de alto poder poluidor. Sem o devido tratamento, quando lançado nos rios compromete a sobrevivência da biota como um todo. O objetivo deste trabalho consistiu em avaliar a eficiência e aplicação do processo Foto-Fenton, seguido por um tratamento biológico (lodo ativado), para a redução da carga orgânica do efluente em questão. A caracterização do efluente lácteo in natura e tratado foi realizada empregando-se métodos estabelecidos e otimizados [DQO, COT, DBO5, Nitrogênio (orgânico e amoniacal), Fósforo total, Ferro, e Sólidos (ST, STF, STV), fenol, análise de elementos via absorção atômica]. Por meio de planejamentos estatísticos - Taguchi, Box-Behnken e fatorial completo - foram determinados os melhores experimentos posteriores aos tratamentos fotocatalíticos e biológico, tendo como variável resposta a redução percentual de COT. Após o processo fotocatalítico, a amostra do melhor experimento foi tratada por um processo biológico (Sistema Lodo Ativado SLA), a fim de verificar a eficiência de degradação da matéria orgânica do efluente estudado através do sistema conjugado (POA- SLA). O sistema híbrido que apresentou maior eficiência teve como variáveis do processo de tratamento fotoquímico: pH = 3,5; Temperatura = 30 ºC; reagente Fenton ( 35 g H2O2 + 3,6 g Fe2+ ) e potência de radiação ultravioleta de 28 W, para um tempo de reação de 60 minutos. Para o tratamento biológico por lodo ativado, os melhores níveis das variáveis foram realizados em pH = 8 e concentração de lodo de 3,0 g L-1. Os resultados para o tratamento híbrido apresentou percentuais de reduções para COT = 94 %, DQO = 97 % e DBO = 83 %. / The dairy effluent is the residue obtained from the improvement of milk and its derivatives, being considered a high pollutant. Without the due treatment, when thrown in the rivers it puts in risk the survival of the biota as a whole. The objective of this work consisted of evaluating the efficiency and application of the process photo-Fenton followed by a biological (activated sludge) treatment for the reduction of the organic load of the effluent. The characterization of the dairy effluent in natura and treated was accomplished using established methods [COD, TOC, BOD5, Nitrogen (organic and amoniacal), Total Phosphorus, Iron, and Solids (TS, FTS, VTS), phenol, analysis of elements through atomic absorption]. Through statistical designs, Taguchi, Box-Behnken and Full Factorial, the best experiments were determined for the photocatalytic and biological treatments having the reduction of TOC as their response. After the photocatalytic process, the sample of the best experiment was treated by a biological process in order to verify the efficiency of degradation of the organic matter of the effluent studied through the conjugated (AOP - AS) system. The hybrid system that presented larger efficiency had as factors of the photochemical treatment: pH = 3,5, temperature = 30 ºC, Fenton\'s reagent (35g H2O2 + 3,6 g Fe2+) and potency of ultraviolet radiation of 28 W, for 60 minutes of reaction time. As for the biological treatment, it was accomplished in pH = 8 and concentration of sludge of 3g L-1. Obtained were of the hybrid system the percentage of reductions of TOC = 94 %, COD = 97 % and BOD = 83 %.

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

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

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

This study investigates the rate kinetics for BD and PGMEA oxidation by UV/O3 process. The reactor constructs of a 100 cm x 20 cm x 85 cm (L x W x H) stainless steel chamber, in which four vertical steel plates (20 cm x 65 cm, W x H) were inserted to establish a plug flow path for the flowing gas. The reactor has a total effective volume of 170 L. Each of the five compartments of the reactor is equipped with an individual UV irradiation system with a 3.0-cm x 15-cm (ID x L) quartz sheath that housed an UV lamp, and two electric UV power inputs of 0.147 or 0.294 W/L were obtained. The gas flows perpendicularly to the UV lamps in the reactor. The influent tested VOC concentration was adjusted to about 50 ppm, and the gas flows were controlled at the individual flow rate of 60 and 120 L/min. The effects of moisture content (relative humidity, RH), ozone dosage (initial molar ratio of ozone to the tested VOC, m) and UV volumetric electric power input on the removal of the tested VOCs are investigated in the study. Also, kinetic models of the tested VOCs by photolysis, ozonation and UV/O3 have been developed and confirmed with reference to the experimental data. According to the kinetic models, both photolysis rate and oxidation rate by UV/O3 are following the first order behavior with respect to the tested VOC concentrations which are low. The result reveals the absorbance for the reactions is weak absorbance under UV irradiation. The reaction rates are proportional to the UV electric power inputs in UV-initiated reactions. And the parameter, £i, which represents the ratio of OH radical consumption rate by the tested VOC to the total OH radical consumption rate, can be obtained by simulating the performance of experimental data of OH reactions. The experimental results reveal that for BD oxidation with a gas space time of 85 sec and RH = 40 ¡V 99%, BD photolysis did not occur at wavelength of 185 nm with UV electric power inputs of 0.147 and 0.294 W/L. The ozonation efficiency of BD reached 90% at m = 3.5, and RH had no influence on the removal efficiency of BD. The removal efficiencies by UV/O3 process reached 90% with m = 2.2 and 1.6 for UV power inputs of 0.147 and 0.294 W/L, respectively. The addition of ozone apparently encouraged BD removal efficiency by UV/O3 process. And the enhancement of ozone dosage (m = 0.5 ¡V 4.4) would promote the decomposition of BD more effectively than the enhancements of UV power input (from 0.147 to 0.294 W L-1) and RH (from 40 to 99%). For PGMEA photolysis in a batch reactor with volume of 1.188 L, the photolysis occurred at wavelength of 185 nm under UV irradiation. And the photolysis rate follows the first order behavior with respect to the concentration of PGMEA. But PGMEA photolysis did not occurred at UV wavelength of 254 nm. PGMEA ozonation was performed in the same batch reactor; and the removal efficiency of only 50% at m = 3.96 would take 35 min. So, PGMEA ozonation in the plug flow reactor did not be observed at the conditions of the gas space time of 85 sec and RH = 15 ¡V 99%. Besides, the photolysis of PGMEA was carried out at the above conditions. The removal efficiency of PGMEA by UV/O3 could reach 90% at the conditions of the gas space time of 170 sec, UV volumetric electric power input of 0.294 W/L and m = 2.9. And the enhancement of UV power input (from 0.147 to 0.294 W L-1) would promote the decomposition of PGMEA more effectively than the addition of ozone dosage (m = 1.05 ¡V 15.63) and RH = 15 ¡V 99%.

DMSO (dimethyl sulfoxide) is a liquid with a high boiling point (189 oC) that has been extensively utilized in various industries owing to its ability to dissolve various organic and inorganic compounds. DMSO is increasingly being adopted as a detergent or a photo-resistant stripping solvent in manufacturing semiconductors and liquid crystal displays (LCD). Therefore, DMSO is now a major component of wastewater. The biological treatment of DMSO-containing wastewater generates noxious DMS (dimethyl sulfide) and other compounds that may cause odor problems. Also having a high water solubility and a moderate boiling point (110 oC), tetrafluoro propanol (TFP) has been extensively applied in the manufacture of CD-R and DVD-R, due to its ability to dissolve organic dyes. The spin coating process produces a large amount of wastewater containing TFP. No reports have been written on the biodegradability of TFP to the authors¡¦ knowledge. Additionally, HMDS (hexamethyldisilazane) has been extensively used in life science microscopy and material science. For instance, the semiconductor industry employs HMDS to promote the adhesion of photo-resistant material to oxide(s). HMDS is classified as a carcinogen, and has an ammonia odor. Condensing incinerators have been found to be unsuitable for treating HMDS-containing waste gases, because of the formation of silicon dioxide, which blocks porous adsorbents. Biological treatment also appears to be unpromising due to its low water solubility and limited biodegradability. This investigation evaluates the feasibility, effectiveness and oxidation characteristics of aqueous DMSO, TFP and gaseous HMDS (hexamethyldisilazane) by UV/O3 processes. A reactor made entirely of acrylic plastic with an effective volume of 10 L was employed for the reactions. The tested VOCs concentrations were adjusted to 400¡V890mg/L and 772¡V887 mg/L for DMSO and TFP, respectively, and the gas (ozone-enriched air) flow rate was controlled at 3L/min. The effects of various solution pH values (acidic, alkaline, uncontrolled), solution temperatures (26 oC, 37 oC, 48 oC and 60 oC), and UV wavelengths (254 nm and 185+254 nm) on the removal of tested VOCs were studied . Additionally, the operation costs of treating DMSO and TFP by UV/O3 were estimated. Experimental results demonstrate that acidic conditions (pH = 3.6) favored the degradation of DMSO, and that the removal efficiency could reach 95% at a volumetric UV intensity P/V of 2.25 W/L and a reaction time of 120 min. However, alkaline conditions (pH = 9.5) favored the decomposition of TFP, with the removal efficiency reaching 95% at P/V = 2.5 W/L and a reaction time of 60 min. Both DMSO and TFP exhibited zero-order degradation kinetics when sufficient ozone was supplied. Raising the oxidation temperature did not increase the UV/O3 oxidation of TFP in the tested concentration and temperature ranges. Operation costs of the UV/O3 per unit volume of wastewater with DMSO or TFP are comparable to those of the methods described in the literature. For the gaseous HMDS oxidation, two batch reactors with effective volumes of 1.2 and 5.8 L were used employed with the decomposition occurred under UV (185+254 nm) irradiation and UV (254 nm)/O3 processes. Tests were performed with initial HMDS concentrations of 32¡V41mg/m3 under various initial ozone dosages (O3 (mg)/HMDS (mg) =1¡V5), atmospheres (N2, O2, and air), temperatures (28 oC, 46 oC, 65 oC and 80 oC), relative humilities (20%, 50%, 65% and 99%) and volumetric UV power inputs (0.87 W/L, 1.74 W/L, 4.07 W/L and 8.16 W/L) to assess their effects on the HMDS degradation rate. Results of this study demonstrate that the decomposition rates for the UV (185+254 nm) irradiation exceeded those for the UV (254 nm)/O3 process for all conditions. UV (185+254 nm) decompositions of HMDS displayed apparent first-order kinetics. A process with irradiation of UV (185+254 nm) to HMDS in air saturated with water at temperatures of 46¡V80 oC favors the HMDS degradation. With the above conditions and a P/V of around 8 W/L, k≈ 0.20 s−1, and over 90% of the initial HMDS was degraded in a time of 12s. The main mechanisms for the HMDS in wet air streams irradiated with UV (185+254 nm) were found to be caused by OH free radical oxidation produced from photolysis of water or O (1D) produced from photolysis of oxygen. Economic evaluation factors of UV (185+254 nm) and UV (254 nm)/O3 processes at various UV power inputs were also estimated.