Dans le cadre de l'élimination de composés réfractaires contenu dans une matrice complexe, les procédés d'oxydation avancée s'avèrent être une technologie de choix. Cette étude est donc consacrée à la sonolyse et à la photolyse de deux xénobiotiques organiques, le naphthol blue black (un colorant hydrophile, noté NBB) et le nonylphénol (un détergent, hydrophobe et volatil, noté NP), seuls ou en compétition. L'efficacité de la technique ultrasonore de haute fréquence (278 kHz) a été testée sur les molécules cibles et leur mélange. La décoloration du NBB est effective après 180 min de traitement et s'accompagne d'une minéralisation de 23% alors que le NP se dégrade après 120 min. L'effet des paramètres a été étudié, tels que la puissance ultrasonore, la concentration du substrat, le pH, les ions inorganiques (bicarbonates et phosphates) et la compétition. Ainsi dans le mélange, la présence du NBB n'a pas d'influence sur la disparition sur NP tandis que la décoloration du NBB est affectée par la présence du NP. Cependant, la présence des ions bicarbonates dans le mélange permet par l'intermédiaire des radicaux carbonates de contrebalancer l'effet inhibiteur du NP. L'utilisation de la photolyse directe a fait l'objet de la deuxième partie de ce travail, ce qui a permis de faire une étude comparative des deux techniques. Il a été montré que la sonochimie, fort de sa capacité à produire abondamment les radicaux HO•, est plus adaptée au traitement des effluents relativement plus concentrés. De plus, la sonochimie permet de mettre en valeur les ions inorganiques, constituants naturels de l'eau pour minimiser l'effet inhibiteur de la matrice. Ensuite, l'efficacité de certains Procédés d'Oxydation Avancée (POA) sur l'élimination des xénobiotiques sus-mentionnés a été testée et les résultats obtenus ont donné lieu à l'ordre suivant : UV < UV/H2O2 < Fe2+/H2O2 < UV/Fe2+/H2O2. / Within the framework of the destruction of refractory organics contained in a complex aqueous matrix, the advanced oxidation processes appear to be a first class technology. So this survey is dedicated to the sonolysis and the photolysis of two organics, namely the naphthol blue black (an acid azo-dye, hydrophilic, noted NBB) and the nonylphenol (a detergent, hydrophobic et volatile, noted NP), single or in competition. High frequency (278 kHz) ultrasound is found to be efficient. NBB decolorization is effective within 180 min and its mineralization reaches 23% while NP is degraded for 120 min. Different parameters were studied, such as ultrasound power, substrate concentration, pH, inorganic ions (bicarbonate and phosphate), and competition. In the NBB/NP mixture, NBB has no influence on the NP degradation whereas NP has a strong effect on the NBB decolorization. Nevertheless, the presence of bicarbonate ions in the mixture reduces the negative effect of NP, thanks to the formation of carbonates radicals. Direct photolysis is the topic of the second part of this study, so as to make a comparison of these two oxidative techniques. It was emphasizes that sonolysis is most adapted for the treatment of more concentrated pollutant, because of the intense production of HO• radicals. Moreover sonolysis is relevant when inorganic ions are present in the mixture, in order to minimize the competition between organics. Then the efficiency of different AOP was tested for the two target pollutants; results can be organized according the following: UV < UV/H2O2 < Fe2+/H2O2 < UV/Fe2+/H2O2.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-02T11:57:41Z No. of bitstreams: 1 MarcellaJordannaSilvaMontorilAraujo_DISSERT.pdf: 3443985 bytes, checksum: 367c6ae398c4c1ef8054fbb595d56752 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-06T20:29:13Z (GMT) No. of bitstreams: 1 MarcellaJordannaSilvaMontorilAraujo_DISSERT.pdf: 3443985 bytes, checksum: 367c6ae398c4c1ef8054fbb595d56752 (MD5) / Made available in DSpace on 2017-02-06T20:29:13Z (GMT). No. of bitstreams: 1 MarcellaJordannaSilvaMontorilAraujo_DISSERT.pdf: 3443985 bytes, checksum: 367c6ae398c4c1ef8054fbb595d56752 (MD5) Previous issue date: 2016-07-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A ind?stria t?xtil gera um grande volume de efluentes que, muitas vezes, s?o descartados no meio ambiente sem estarem devidamente tratados. Esses efluentes s?o formados de mol?culas org?nicas e caracterizam-se por apresentar cor, que alteram as propriedades da ?gua deixando-a impr?pria para o consumo. Para o tratamento desses efluentes, a utiliza??o de processos catal?ticos heterog?neos de custo baixo pode ser vantajoso. As argilas v?m sendo bastante estudadas como suportes catal?ticos em raz?o de sua abund?ncia na crosta terrestre e seu baixo custo. Portanto, neste trabalho as argilas vermiculita e bentonita foram usadas como suporte para o catalisador oxihidr?xido de ni?bio e pelo m?todo de deposi??o-precipita??o foram obtidos comp?sitos formados por esses materiais. Os comp?sitos Nb/argila foram caracterizados e as principais t?cnicas mostraram que ocorreu uma modifica??o em cada argila. Os resultados de difratrometria de raios X (DRX) indicaram que ocorreu uma diminui??o da intensidade da reflex?o e um deslocamento do pico principal de ambas as argilas quando o oxihidr?xido de ni?bio ? adicionado na estrutura. As an?lises de espectroscopia na regi?o do infravermelho mostram bandas de adsor??o de ambos os materiais nos comp?sitos Nb/argila, dando a indicativa de que o comp?sito foi realmente formado. As imagens de microscopia eletr?nica de varredura tamb?m confirmaram essa modifica??o de estrutura. Foram realizados testes de oxida??o e oxida??o fotocatal?tica com os comp?sitos obtidos e o teste de oxida??o fotocatal?tica foi o que apresentou melhores resultados, pois o comp?sito de vermiculita (Nb/V0) apresentou uma maior atividade fotocatal?tica removendo 98% da cor do corante alaranjado de metila em 90 minutos de rea??o enquanto que o material comp?sito de bentonita (Nb/B0) removeu apenas 63% durante o mesmo tempo de rea??o. Essa atividade ? devido o comp?sito Nb/V0 ter apresentado um menor valor de band gap (3,08eV) que o comp?sito Nb/B0 (3,33eV). / The textile industry produces a large volume of waste that often is discarded into the environment without being properly treated. These effluents are made of organic molecules and are characterized by their color that alter the properties of water which leave it unfit for consumption. For the treatment of these effluents, the use of heterogeneous catalytic processes of low cost can be advantageous. Clays have been widely studied as catalyst supports because of their abundance in the Earth's crust and its low cost. Therefore, in this study the clays vermiculite and bentonite were used as support for the catalyst oxyhydroxide niobium and by the method of deposition-precipitation it was obtained composites formed from these materials. The composite Nb/clay were characterized and the main techniques showed that was changes in each clay. The results X-ray diffractometer (XRD) showed that there was a decrease in reflection intensity and a shift of the main peak of both clays when oxyhydroxide niobium is added to the structure. The spectroscopic analyzes show infrared adsorption bands of in both materials composite Nb/clay which indicates that the composite was actually formed. The scanning electron microscopy images also confirmed that structure modification. Oxidation and photocatalytic oxidation tests were performed with the obtained composite and photocatalytic oxidation test showed the best results, because the vermiculite composite (Nb/V0) showed higher photocatalytic activity by removing 98% of the color orange dye methyl in 90 minutes of reaction while the composite material of bentonite (Nb/B0) removed only 63% over the same reaction time. This activity is due to the composite Nb/V0 have presented a smaller value of band gap (3,08eV) than the composite Nb/B0 (3,33eV).

Orientadores: José Roberto Guimarães, Carlos Gomes da Nave Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-18T03:12:06Z (GMT). No. of bitstreams: 1 Gasparini_MirthysCozzett_M.pdf: 1574617 bytes, checksum: 879f212f74e005fca5974d6f943a790e (MD5) Previous issue date: 2011 / Resumo: No presente trabalho foi realizada a caracterização de várias correntes de águas de processo da REPLAN (Refinaria de Paulínia), bem como a avaliação dos processos de fotólise (UV), peroxidação (H2O2), peroxidação assistida por radiação ultravioleta (H2O2/UV), reagente de Fenton (H2O2/Fe2+) e foto-Fenton (H2O2/Fe2+/UV) no tratamento de um dos efluentes, principalmente na degradação dos compostos orgânicos. Analisando-se os dados de caracterização dos diferentes efluentes foi possível sugerir alternativas de reuso no processo de refino, como também selecionar a corrente de água ácida retificada para aplicação dos processos físico-químicos de tratamento. A eficiência dos ensaios de tratabilidade foi baseada na redução da concentração do carbono orgânico dissolvido (COD). Dentre os processos estudados, os processos oxidativos avançados (POA) H2O2/UV e foto-Fenton apresentaram 95 % de eficiência após 150 minutos de ensaio. As condições ótimas foram obtidas na relação mássica COD: H2O2 de 1:7 para o processo peroxidação assistida por radiação UV, e de 1:5 e concentração de Fe2+ de 31 mg/L para o processo foto-Fenton. O efluente tratado pelo processo H2O2/UV poderia ser reutilizado como água de reposição no sistema de resfriamento, já que esta é responsável por 49 % do total de água utilizada na refinaria / Abstract: In the present study was performed the characterization of various process water from REPLAN (Paulínia Refinery) as well as an assessment of 5 processes to treat one of the effluents: photolysis (UV), peroxidation (H2O2), peroxidation assisted by ultraviolet radiation (H2O2/UV), Fenton reagent (H2O2/Fe2+) and photo-Fenton (H2O2/Fe2+/UV), in order to degrade the organic compounds. Effluents characterization results provided reuse possibilities in the process refining and also selected the stripped sour water stream for application of physical-chemical treatments. The processes efficiency was evaluated by the dissolved organic carbon (DOC) reduction. Among the processes studied, the advanced oxidation processes (AOPs) H2O2/UV and photo-Fenton reached 95 % efficiency after 150 minutes of reaction. The optimum conditions were obtained in a mass ratio COD: H2O2 of 1:7 for peroxidation assisted by UV radiation, and of 1:5 with 31 mg/L of Fe2+ for photo-Fenton. The effluent treated by AOP H2O2/UV could be reused as make-up water in cooling systems, since it is responsible for 49 % of the total water used in the refinery / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil

Orientador: Wilson de Figueiredo Jardim / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-05T10:39:52Z (GMT). No. of bitstreams: 1 Andrade_JulianodeAlmeida_M.pdf: 3254677 bytes, checksum: 72d1e108844df115bda11c77f7fd1337 (MD5) Previous issue date: 2005 / Mestrado / Quimica Analitica / Mestre em Química

Orientador: Wilson de Figueiredo Jardim / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-24T02:49:05Z (GMT). No. of bitstreams: 1 Torres_CarolinaFerreira_M.pdf: 3163293 bytes, checksum: 169b47e5a4d52ba3e29d4ad8c88bec54 (MD5) Previous issue date: 2013 / Resumo: O uso de fotocatalisadores suportados tem sido a estratégia preferencial em fotocatálise heterogênea, uma vez que a separação do material fotoativo do meio reacional é difícil e dispendiosa. A quitosana é um biopolímero de disponibilidade ilimitada, fonte renovável, é biodegradável e possui alto poder de adsorção. Esferas de quitosana impregnadas com TiO2 P-25 foram obtidas pela técnica de coagulação, onde uma mistura de quitosana e TiO2 P-25 é dissolvida em meio ácido e gotejada sobre um banho alcalino formando as esferas. Depois de lavadas e secas estas foram caracterizadas quanto à sua morfologia, resistência à solução ácida e à fotodegradação, área superficial, DRX, refletância de radiação UV/Vis e absorção de radiação IV. A atividade fotocatalítica das esferas foi avaliada utilizando solução de ácido salicílico 50 mg L. Placas de Petri contendo 0,5 g de esferas com relação quitosana: TiO2 P-25 na proporção de 1:10 (m/m) e 25 mL de solução de AS foram iluminadas por radiação UV e em intervalos de 8 horas alcançou-se mineralização de 40%, determinado por medidas de COT e emissão de fluorescência. As esferas foram reutilizadas em mais dois ciclos de ensaios de fotodegradação sem que passassem por qualquer processo de limpeza e sem perderem sua atividade fotocatalítica. / Abstract: The use of supported photocatalysts has been the preferred strategy for heterogeneous photocatalysis, since the separation of photoactive material from the reactional mean is difficult and expensive. Chitosan is a biopolymer of unlimited availability; it is a renewable source, biodegradable and has a high adsorption power. Chitosan beads impregnated with TiO2 P-25 were obtained by the coagulation technique, where a mixture of chitosan and TiO2 P-25 is dissolved in an acidic mean and dripped onto an alkaline bath, forming the spheres. Once washed and dried, they were characterized as to their morphology and resistance to acid solutions and photodegradation, as well as to their surface area, XRD, UV/Vis radiation reflectance and IR radiation absorption. The photocatalytic activity of the spheres was evaluated using salicylic acid solution 50 mg L. Petri dishes containing 0.5 g of beads with chitosan proportion: TiO2 P-25 at a ratio of 1:10 (w/w) and 25 mL of SA solution were illuminated by UV radiation and within 8-hour intervals a mineralization of 40% was reached, as determined by TOC measures and fluorescence emission. The beads were reused in two other test cycles of photodegradation without undergoing any cleaning process and without losing its photocatalytic activity. / Mestrado / Quimica Analitica / Mestra em Química

Nitrogen (N) is the most commonly over-applied nutrient in urban environments because of the large visual and growth increases. This over-application has led to an increase in the loss of N gas in the forms of ammonia and nitrous oxide, as well as an increase in nitrate leaching to surface and groundwater. Furthermore, excess N results in increased maintenance costs and landfill volume due to increased shoot growth from mowed clipping removal. Polymer coated urea (PCU) has proven to be an excellent source to these losses of N to the environment, but rate and timing parameters need study. A two-year field study, on sand and sandy loam soils in Provo, UT, was initiated in April 2014. Seven fertilized treatments included: urea split applied monthly; a single application of PCU (Agrium One Ap) applied in spring, a single PCU application in fall; two evenly split applications in spring and late summer; and three evenly split applications in spring, late summer, and late fall. These were compared to an untreated control. In addition the two application of PCU also had reduced rates of half and three-quarters, in addition to the full rate. Height and verdure measurements were taken on a weekly basis, along with periodic visual and biomass readings. All fertilized treatments resulted in a significant response to N as compared to the control. The single annual application treatments had significantly greater shoot growth during the weeks immediately after application and a significant reduction in verdure months later and, therefore, were unacceptable for consumer recommendation. Two applications of PCU, either at the three-quarter or full rates, were nearly identical in all measurements as compared to the spoon feeding of urea applied monthly. The half rate of two applications showed signs of inadequate N. Three applications of PCU was identical to two and, therefore, not recommended. This study shows two applications of PCU at the three-quarter rate is equally effective as spoon feeding the N. Doing so would result in less labor for fertilization. Further work is needed to evaluate other timing approaches for a single annual application, as well as long term effects of a reduced rate of N.

<p>  </p> <p>Annual bluegrass (<em>Poa annua</em> L.) is the most troublesome weed in turfgrass systems and the second most troublesome weed across all grass crops. Controlling annual bluegrass is exceptionally complicated due to its high genetic adaptability to new environments. Additionally, prolific seed production allowed the rapid development of herbicide resistance to 12 herbicide modes of action. Experiments were initiated with the goal to better understand annual bluegrass ecology and resistance to ethofumesate. A dose-response experiment was initiated in 2022 to determine the potential level of ethofumesate resistance in annual bluegrass collected from seed production systems. Seed from 55 annual bluegrass populations was obtained from three sources: seed production fields (31 populations), seed cleaning process (6 populations), and seed testing prior to retail distribution (18 populations). </p> <p>Individual seedlings (2–3 tillers) were treated with ten doses of ethofumesate: 0, 0.6, 1.1, 2.8, 5.6, 8.4, 11.2, 16.8, 22.4, and 44.8 kg ai ha−1; with 1.1 to 2.2 kg ha−1 as the label application rates for perennial ryegrass (<em>Lolium perenne</em> L.). The resistance to susceptible ratio of populations across all sources ranged from 0.48 to 5.48. The most resistant populations from production fields, removed during the seed cleaning process, or found in seed testing lots had ED50 values of 12.1, 13.1, and 9.4 kg ai ha−1, respectively. Further, 68% of the populations found in production fields had ED50 higher than 6 kg ai ha−1, which indicates that annual bluegrass resistance is common in grass seed production. A garden study was initiated in November 2020 to assess the development, reproduction, and survival of ten annual bluegrass populations in Indiana. Annual bluegrass plants were maintained in the absence of turf competition and not subjected to typical turfgrass management practices including irrigation, mowing and fertilization. Data collected in included growth rate, biomass production, ground cover, morphology, flowering time, seed production and morphology, and both winter survival and subsequent summer survival of plants. Principal component analysis indicated that certain populations grouped together based on their development, morphology, stress tolerance, and seed production. Plants from the cooler climates (OR, PA, and IN) were characterized by higher growth rates and biomass compared to southern ecotypes. These three populations survived the longest during the summer, with the PA population averaging the highest ground cover of 276 cm2 on 23 July 2021. Plants from warm climates (AL, FL, NC, SC, TN, TX) had poor summer survival. Additionally, the FL population had the highest winterkill of 68%, followed by TX at 45%. The NJ population was distinct from other populations, and plants had robust aboveground biomass and high seed production. The results indicate that the development, reproduction, and survival of different annual bluegrass biotypes are dependent on the climate of origin. A third experiment was designed to understand patterns of germination and seed longevity in populations from five climates across the U.S. at two depths of burial. Seed was retrieved in 6-month intervals up to 24 months. Seed viability by depth (surface vs. 5-cm deep) of burial differed only 18 months after the initiation of the study. However, seed viability did differ among populations on each date of seed retrieval. Viability was low ranging from 0.21 to 0.91%, and populations originating from cool climates (New Jersey, Pennsylvania, and Oregon) generally had higher viability than populations originating from warmer climates. Annual bluegrass seed tested in this study typically had low levels of survival (<0.5%); however, all populations retained some level of viability 24 months after burial, which would allow future reproduction of this troublesome weed. Overall, this research determined that herbicides alone will likely be ineffective at controlling annual bluegrass and that knowledge of the development, reproduction, and survival of local annual bluegrass populations should be factored into an integrated weed management strategies created for each site. </p> <p>  </p>

L'usage intensif de pesticides dans l'agriculture engendre une contamination sans précédent des eaux de surface et des nappes phréatiques. Les traitements classiques appliqués aux eaux usées contenant des produits organiques polluants sont basés sur la biodégradation ou sur des méthodes physiques de transfert de masse (décantation, filtration, adsorption des polluants sur du charbon actif) ou des procédés chimique tels que l'oxydation à l'ozone ou au chlore. Cependant, ces procédés demeurent inefficaces dans le cas de traitement des eaux contaminées par les polluants organiques persistants (POPs). Les procédés d'oxydation avancés sont mis en œuvre pour dégrader ou même minéraliser ces polluants. Ce travail a donc pour objectif de déterminer un protocole expérimental pour détruire efficacement les pesticides, produits chimiques largement utilisés dans l'agriculture au Maroc, tels que le monochloro-benzène, le 1,2-dichlorobenzène, l'acide 2,4,5-trichlorophénoxy-acétique, et l'imazalil en utilisant les procédés d'oxydation avancée électro-Fenton et oxydation anodique avec différentes anodes telles que BDD, Pt et DSA. Ainsi, nous avons trouvé que le taux de minéralisation par procédé électro-Fenton avec l'anode BDD était de 92%, 95%, 92% et 97%pour le monochloro-benzène, le 1,2-dichlorobenzène, l'acide 2,4,5-trichlorophénoxy-acétique, et l'imazalil, respectivement, après 4 h de traitement. Ces résultats confirment l'efficacité des procédés d'oxydation avancés électrochimiques dans le traitement des eaux polluées par des pesticides / The intensive use of pesticides in agriculture generates, nowadays, an unprecedented contamination of surface water and groundwater. Conventional treatments applied to waste water containing organic pollutants are based on biological treatments méthods or physical mass transfer methods (decantation, filtration, adsorption of the pollutants on activated carbon), chemical oxidation with ozone, chlorine, etc. However, these methods remain ineffective for the treatment of water polluted by persistent organic pollutants (POPs). Advanced oxidation processes are implemented to degrade and mineralize these pollutants. This PhD thesis work aims to establish an experimental protocol to degrade and mineralize pesticides, chemicals widely used in agriculture in Morocco, such as monochlorobenzene, 1,2-dichlorobenzene, 2,4,5-trichlorophenoxy-acetic acid , and imazalil using the electro-Fenton and anodic oxidation processes with DD Pt or DSA anodes. Thus, the rate of mineralization was 92%, 95%, 92% and 97% for the monochloro-benzene, the 1,2-dichlorobenzene, the 2,4,5-trichlorophenoxyacetic acid , and the imazalil, respectively, after 4 h treatment by electro-Fenton process. These results confirm the effectiveness of electrochemical advanced oxidation processes for treating water polluted by pesticides

Neste trabalho, foram sintetizados complexos de cobre e ferro, com ligantes imínicos, obtidos a partir de 2-acetilpiridina e 2-(2-aminoetilpiridina) (apyepy), ou 2-acetilpiridina e 2-(aminometil)benzimidazol (apyambi), e com ligantes comerciais (ácido nitrilotriacético ou picolínico), capazes de catalisar a oxidação de poluentes, como benzeno, tolueno, etilbenzeno e xilenos (BTEX). Foi utilizado o tolueno como composto-modelo destes poluentes, que foi degradado com o uso de peróxido de hidrogênio, persulfato de sódio, ácido peracético ou peróxidos de metais alcalinos como agentes oxidantes. Os ligantes imínicos foram obtidos a partir de precursores carbonílicos e amínicos adequados, através de reações de condensação, e os correspondentes complexos metálicos de cobre(II), ferro(II) ou ferro(III) foram isolados utilizando métodos usuais de nosso laboratório. A caracterização dos compostos foi feita através de diversas técnicas analíticas e espectroscópicas: UV/Vis, infravermelho (IV) e de ressonância paramagnética eletrônica (EPR). Posteriormente, foi feita a inserção desses complexos de ferro e de cobre sintetizados em matrizes inorgânicas de niobatos e a verificação de sua reatividade em comparação com as mesmas espécies em solução. Monitorou-se a degradação do tolueno pelo peróxido de hidrogênio por cromatografia gasosa e os resultados obtidos indicaram boa atividade catalítica dos complexos, tanto em solução como inseridos em matrizes de niobato. Em solução, os complexos imínicos foram mais ativos que os de ligantes comerciais. Os compostos de ferro com ambos os ligantes imínicos mostraram-se melhores catalisadores que os correspondentes de cobre e um dos ligantes testados foi o mais eficiente (apyepy) com ambos os metais. A inserção em niobatos, aparentemente, preserva o catalisador e mantém sua atividade por mais tempo, mostrando que a inserção em niobatos beneficia o processo / In this work, iron and copper complexes were synthesized, with imine ligands obtained from 2-acetylpyridine and 2-(2-aminethylpiridine) (apyepy), or 2- acetylpyridine and 2- (aminomethyl)benzimidazole (apyambi) and commercial ligands (nitriletriacetic and picolinic acids) that are able to catalyze the oxidation of pollutant compounds as benzene, , ethylbenzene and xilenes (BTEX). Toluene was used as model compound of those pollutants, and its degradation was verified by using hydrogen peroxide, alkaline peroxide, sodium persulfate, or peracetic acid as oxidant agent. The imine ligands were obtained from adequate carbonyl and amine precursors, in condensation reactions, and the corresponding copper(II), iron(II) and iron(III) complexes were isolated by usual methods developed in our laboratory. Their characterization was carried out by analytical and spectroscopic techniques (UV/Vis, IR and EPR). Those complexes were then inserted in inorganic matrices (niobates) e its reactivity were compared to that of the analogous species in solution. Toluene degradation by hydrogen peroxide was monitored by gas chromatography, and the results showed good catalytic activity of all the complexes, both in solution and inserted into niobate matrices. In solution, the imine complexes were more efficient than the species with commercial ligands. The iron compounds with both imine ligands acted as better catalysts than the corresponding copper species, and for both metals those with the ligand apyepy were the most efficient in both cases. The insertion in niobates apparently preserves the catalyst and maintains its activity for longer, attesting that the insertion ameliorated the process.

Alguns dos chamados processos oxidativos avançados (POA) foram aplicados após um processo biológico anaeróbio no tratamento de efluentes do processo industrial de branqueamento da polpa celulósica, visando a aumentar a biodegradabilidade desses efluentes e remover compostos tóxicos, de modo a permitir que um posterior tratamento biológico possa ser mais eficiente e atender às regulamentações ambientais. Para que esse objetivo fosse alcançado, as seguintes etapas de tratamento foram realizadas: processo biológico realizado em reator anaeróbio horizontal de leito fixo (RAHLF), visando à redução inicial da carga orgânica do efluente, seguido de aplicação de um dos POA: 'O IND.3', 'O IND.3'/'H IND.2'O IND.2', 'O IND.3'/UV, UV, 'H IND.2'O IND.2', 'H IND.2'O IND.2'/UV e 'O IND.3'/'H IND.2'O IND.2'/UV, visando a aumentar a biodegradabilidade dos compostos recalcitrantes encontrados no efluente do primeiro tratamento biológico e diminuir a toxicidade. No tratamento biológico, a biomassa anaeróbia se adaptou facilmente à água residuária. Dessa forma, o reator atingiu a estabilidade e apresentou eficiências de remoção de DQO e AOX adequadas para esta etapa da pesquisa (média de 50%), satisfazendo o objetivo de promover uma redução inicial da matéria orgânica de fácil degradação presente nessa água residuária. Com relação aos POA, foi concluído que todos os processos testados provocaram modificações na biodegradabilidade do efluente do RAHLF. O processo 'O IND.3'/UV, realizado em meio neutro, foi considerado o mais eficiente, provocando um aumento de biodegradabilidade de 160%, após 45 minutos de oxidação com uma concentração de ozônio de 1155 mg/L. Através da análise de AOX, observaram-se também degradações médias dos compostos organoclorados maiores que 95% para todos os processos testados. Os resultados gerais mostram a importância e a vantagem de se utilizar um POA como complemento de um tratamento biológico para efluentes de baixa biodegradabilidade, provocada pela presença de compostos recalcitrantes e tóxicos. / Some advanced oxidation processes (AOP) were applied after an anaerobic process for the treatment of bleaching effluents from a kraft pulp mill, aiming the increase of the effluent biodegradability and the removal of toxic compounds, in a way that a further biological treatment could be more efficient to attain the environmental regulations. A horizontal anaerobic imobilizaded sludge reactor (HAIS) was used as the anaerobic treatment in order to reduce the effluent initial organic load. The AOP used were 'O IND.3', 'O IND.3'/'H IND.2'O IND.2', 'O IND.3'/UV, UV, 'H IND.2'O IND.2', 'H IND.2'O IND.2'/UV and 'O IND.3'/'H IND.2'O IND.2'/UV. These AOP were not applied only to promote a further degradation of the remaining COD from the HAIS reactor, but in order to increase the effluent biodegradability and eliminate AOX or other toxic compounds from this effluent. In this way, the AOP would provide an effluent with characteristics to be easily treated by a further and final biological process. In the biological process, the anaerobic biomass was fast adapted to the wastewater. The HAIS reactor reached the stability and had efficiency in COD and AOX removals of approximately 50%, satisfying the aim of promoting an initial reduction in the easy-to-degrade organic matter presented in the bleaching effluents. All the tested AOP promoted modifications in de HAIS effluent biodegradability. The 'O IND.3'/UV at pH 8 was the more efficient process, achieving an increase of 160% on the biodegradability of the HAIS effluent after 45 minutes of oxidation and an ozone concentration of 1155 mg/L. By the AOX analyses, it was observed average degradations of the organochlorine compounds higher than 95% for all the AOP tested. The general results show the importance and the advantage of using an AOP as a complement of a biological treatment process for the degradation of effluents with low biodegradability, due to the presence of recalcitrant and toxic compounds.