Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-08-18T16:17:20Z No. of bitstreams: 1 2010 - Janaina de Faria Rodrigues.pdf: 2153676 bytes, checksum: 8429cd74e923c45f3d05970bcdff87d2 (MD5) / Made available in DSpace on 2017-08-18T16:17:20Z (GMT). No. of bitstreams: 1 2010 - Janaina de Faria Rodrigues.pdf: 2153676 bytes, checksum: 8429cd74e923c45f3d05970bcdff87d2 (MD5) Previous issue date: 2010-06-15 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil. / By laser flash photolysis, the photo-reactivity of the triplet excited state of thioxanthone derivatives (2BTX, 2MeOTX, 2PrOTX and 2MeTX) was studied. The maximum wavelength and triplet time life of theirs transients are solvent dependents, a blue-shift is observed with the change of no polar to polar middle and still more in hydroxyl solvent. The triplet spectrum with hydrogen-donor solvents shows a slower broad band between 430-460nm that again is observed with hydrogen-donor quenchers, this band is attributed to ketyl radical. The broad bands in 410 and 500nm are attributed to phenoxyl, indolyl radicals and ions radicals as intermediates, respectively. The higher values to hydrogen transference from alcohols (~105 M-1s-1) and allylic hydrocarbons and phenols (~109 M-1s-1) are attributed to the triplet excited state of lower energy have a mixture of excited states with predominant character of the excited state with n?*. The no dependence to substituted-phenols on Kq and the approximated values between then and TEA, DABCO and indole (~109 M-1s-1) are indicating a mechanism by electron-transference followed a faster proton transference from an exciplex. The quenching rate contants by transfer of energy from trans-stilbene, 1-methylnaphthalene and 1,3-cyclohexadiene are controlled by diffusion for 2MeTX remaining triplet energy over 61 kcal.mol-1, as observed for TX. For the other substituents was a decrease in triplet energy is getting between 53 and 61 kcal.mol-1. / Utilizando-se a t?cnica de fot?lise por pulso de laser, foram estudadas a fotorreatividade do estado triplete de derivados de tioxantona (9-H-tioxanton-9-ona). Os espectros de absor??o T1?Tn para os derivados 2-benzil?xi, 2-met?xi, 2-prop?xi e 2-metil (2BTX, 2MeOTX, 2PrOTX e 2MeTX), obtidos em diversos solventes, mostram que estes se comportam de forma selhante a tioxantona. O comprimento de onda m?ximo bem como o tempo de vida de seus transientes s?o dependentes da polaridade do meio. Observou-se o deslocamento hipsocr?mico com a mudan?a de um solvente apolar para um solvente polar, tendo sido mais acentuado para os solventes polares hidroxil?cos. Nos espectros de absor??o T1?Tn em solventes doadores de hidrog?nio foi poss?vel observar a forma??o de uma banda entre regi?o de 430-460nm que foi observada novamente nas rea??es com supressores de energia triplete doadores de hidrog?nio, sendo esta banda atribu?da ao radical cetila. As bandas formadas na regi?o de 410 e 500nm s?o atribu?das ao radical fenoxila e indolila, respectivamente. Os altos valores para as constantes de velocidade de rea??o de supress?o por transfer?ncia de hidrog?nio com ?lcoois (~105 M-1s-1), hidrocarbonetos al?licos e fen?is (~109 M-1s-1) s?o atribu?dos ao fato de que o estado excitado triplete de mais baixa energia apresentar uma mistura de estados excitado com predomin?ncia do car?ter n?*. A n?o depend?ncia das kq para os fen?is de seus substituintes e os valores pr?ximos das rea??es para trietilamina, DABCO e indol indicam que o mecanismo de rea??o passa por uma primeira etapa de transfer?ncia de el?trons seguida de uma r?pida transfer?ncia de pr?ton a partir da forma??o de um exciplexo. As constantes de velocaide de rea??o de supress?o por transfer?ncia de energia com trans-estilbeno, 1-metil-naftaleno e 1,3-cicloexadieno s?o controladas por difus?o para 2MeTX estando a energia triplete de T1 acima de 61 kcal.mol-1, como o observado para a TX; j? para os demais substituintes houve uma diminui??o da energia triplete ficando esta entre 53 kcal.mol-1 e 61 kcal.mol-1.

Made available in DSpace on 2014-12-17T15:01:16Z (GMT). No. of bitstreams: 1 DouglasNS.pdf: 627007 bytes, checksum: b05193ec4ef1bbecaf4b2d739179e597 (MD5) Previous issue date: 2002-10-10 / Photo-oxidation processes of toxic organic compounds have been widely studied. This work seeks the application of the photo-Fenton process for the degradation of hydrocarbons in water. The gasoline found in the refinery, without additives and alcohol, was used as the model pollutant. The effects of the concentration of the following substances have been properly evaluated: hydrogen peroxide (100-200 mM), iron ions (0.5-1 mM) and sodium chloride (200 2000 ppm). The experiments were accomplished in reactor with UV lamp and in a falling film solar reactor. The photo-oxidation process was monitored by measurements of the absorption spectra, total organic carbon (TOC) and chemical oxygen demand (COD). Experimental results demonstrated that the photo-Fenton process is feasible for the treatment of wastewaters containing aliphatic hydrocarbons, inclusive in the presence of salts. These conditions are similar to the water produced by the petroleum fields, generated in the extraction and production of petroleum. A neural network model of process correlated well the observed data for the photooxidation process of hydrocarbons / Processos de fotooxida??o de compostos org?nicos t?xicos t?m sido bastante estudados. Este trabalho trata da aplica??o do processo foto-Fenton para a degrada??o de hidrocarbonetos em ?gua. A gasolina de refinaria, sem aditivos e ?lcool, foi usada como poluente modelo. O efeito das concentra??es dos seguintes compostos foi avaliado: per?xido de hidrog?nio (100-200mM), ?ons ferrosos (0,5-1,0mM) e cloreto de s?dio (200-2000ppm). Os experimentos foram realizados em um reator com l?mpada UV e em um reator solar tipo filme descendente. O processo de foto-oxida??o foi monitorado por medidas do espectro de absor??o, carbono org?nico total (TOC) e demanda qu?mica de oxig?nio (DQO). Os resultados experimentais demonstram que o processo foto-Fenton ? vi?vel para o tratamento de efluentes contendo hidrocarbonetos alif?ticos, inclusive na presen?a de sais, sob condi??es similares ?s das ?guas de produ??o de campos de petr?leo, geradas na extra??o e produ??o de petr?leo. Um modelo do processo, baseado em redes neurais, correlacionou bem os dados observados para o processo de fotooxida??o de hidrocarbonetos

Made available in DSpace on 2014-12-17T15:01:50Z (GMT). No. of bitstreams: 1 CarlosEMJ_TESE.pdf: 1404904 bytes, checksum: 3029c558b265d6dfdac69a6fac1ef20c (MD5) Previous issue date: 2010-05-24 / An evaluation project was conducted on the technique of treatment for effluent oil which is the deriving process to improve cashews. During the evaluation the following techniques were developed: advanced processes of humid oxidation, oxidative processes, processes of biological treatment and processes of adsorption. The assays had been carried through in kinetic models, with an evaluation of the quality of the process by means of determining the chemical demand of oxygen (defined as a technique of control by means of comparative study between the available techniques). The results demonstrated that the natural biodegradation of the effluent ones is limited, as result using the present natural flora in the effluent one revealed impracticable for an application in the industrial systems, independent of the evaluation environment (with or without the oxygen presence). The job of specific microorganisms for the oily composite degradation developed the viability technique of this route, the acceptable levels of inclusion in effluent system of treatment of the improvement of the cashew being highly good with reasonable levels of removal of CDO. However, the use combined with other techniques of daily pay-treatment for these effluent ones revealed to still be more efficient for the context of the treatment of effluent and discarding in receiving bodies in acceptable standards for resolution CONAMA 357/2005. While the significant generation of solid residues the process of adsorption with agroindustrial residues (in special the chitosan) is a technical viable alternative, however, when applied only for the treatment of the effluent ones for discarding in bodies of water, the economic viability is harmed and minimized ambient profits. Though, it was proven that if used for ends of I reuse, the viability is equalized and justifies the investments. There was a study of the photochemistry process which have are applicable to the treatment of the effluent ones, having resulted more satisfactory than those gotten for the UV-Peroxide techniques. There was different result on the one waited for the use of catalyses used in the process of Photo. The catalyses contained the mixing oxide base of Cerium and Manganese, incorporated of Potassium promoters this had presented the best results in the decomposition of the involved pollutants. Having itself an agreed form the gotten photochemistry daily paytreatment resulted, then after disinfection with chlorine the characteristics next the portability to the water were guarantee. The job of the humid oxidation presented significant results in the removal of pollutants; however, its high cost alone is made possible for job in projects of reuses, areas of low scarcity and of raised costs with the capitation/acquisition of the water, in special, for use for industrial and potable use. The route with better economic conditions and techniques for the job in the treatment of the effluent ones of the improvement of the cashew possesses the sequence to follow: conventional process of separation water-oil, photochemistry process and finally, the complementary biological treatment / Neste trabalho foram avaliadas t?cnicas de tratamento para os efluentes oleosos oriundos do processo de beneficiamento da castanha de caju. As t?cnicas avaliadas foram: processos de oxida??o ?mida, processos oxidativos avan?ados, processos de tratamento biol?gico e processos de adsor??o. Os ensaios foram realizados com propostas de modelos cin?ticos, com monitoramento da qualidade dos processos por meio da determina??o da demanda qu?mica de oxig?nio (definida como t?cnica de controle por meio de estudo comparativo entre as t?cnicas dispon?veis). Os resultados demonstram que a biodegrada??o natural dos efluentes ? limitada, e os resultados utilizando da flora natural presente no efluente mostrou-se invi?vel para aplica??o em sistemas industriais, independente do ambiente de avalia??o (com ou sem a presen?a de oxig?nio). O emprego de microorganismos espec?ficos para a degrada??o de compostos oleosos incrementou a viabilidade t?cnica dessa rota,em n?veis adequados para aplica??o em sistemas de tratamento de efluentes do beneficiamento da castanha, tendo-se uma boa expressividade, com remo??o da DQO. Por?m, o uso combinado com outras t?cnicas de pr?-tratamento para esses efluentes mostrou-se ainda mais eficiente para o contexto do tratamento de efluentes e descarte em corpos receptores dentro dos padr?es preconizados pela resolu??o CONAMA 357/2005. Apesar da gera??o significativa de res?duos s?lidos, o emprego do processo de adsor??o com res?duos agroindustriais (em especial a quitosana) ? uma alternativa tecnicamente vi?vel, por?m, quando aplicada apenas para o tratamento dos efluentes para o descarte em corpos d ?gua, a viabilidade econ?mica ? prejudicada e os ganhos ambientais minimizados. Por?m, foi comprovado que se utilizado para fins de reuso, a viabilidade ? equiparada e justifica os investimentos. Os processos fotoqu?micos s?o aplic?veis ao tratamento dos efluentes estudados, tendo-se como resultados mais satisfat?rios aqueles obtidos para as t?cnicas de UV-Per?xido. Sendo o resultado diferente do esperado pela utiliza??o de catalisadores usados no processo de Foto-Fenton. Os catalisadores a base de ?xido misto de C?rio e Mangan?s, incorporado de promotores de Pot?ssio, apresentaram os melhores resultados na decomposi??o dos poluentes envolvidos. Os resultados obtidos de forma combinada ao pr?-tratamento fotoqu?mico, ap?s desinfec??o com cloro, garantem caracter?sticas pr?ximas a potabilidade da ?gua. O emprego da oxida??o ?mida apresenta resultados muito significativos na remo??o de poluentes, entretanto, o seu alto custo s? ? viabilizado para emprego em projetos de reuso, em ?reas de baixa escassez e de elevados custos com a capta??o/aquisi??o da ?gua, em especial, para utiliza??o para uso industrial e pot?vel. A rota com melhores condi??es econ?micas e t?cnicas para o emprego no tratamento dos efluentes do beneficiamento da castanha de caju, possui a seq??ncia a seguir: processo convencional de separa??o ?gua-?leo, processo fotoqu?mico e por fim, o tratamento biol?gico complementar

Made available in DSpace on 2014-12-17T15:01:50Z (GMT). No. of bitstreams: 1 OtideneRSR_DISSERT.pdf: 1647726 bytes, checksum: 2a45d120fb2b82e3a84f67c77eff85a3 (MD5) Previous issue date: 2010-09-01 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The petroleum industry deals with problems which are difficult to solve because of their relation to environmental issues. This is because amounts of residue are generated which vary in type and danger level. The soil contamination by non aqueous liquid phase mixtures, specifically hydrocarbon petroleum has been a reason for great concern, mainly the aromatic and polycyclic aromatic, which present risk to human health due to its carcinogenic and mutagenic character. The Advanced Oxidative Processes (AOP) are efficient technologies for destruction of organic compounds of difficult degradation and, often, they are present in low concentrations. They can be considered clean technologies, because there is no formation of solid by-products or the transfer of pollutor phases. This work focuses on the study of the degradation of petroleum industrial waste, by Advanced Oxidation Processes. Treatments tackling petroleum residues, contaminated soil, and water occurring in the production of petroleum reached the following Polycyclic Aromatic Hydrocarbons (PAH) degradation levels: solid residues 100% in 96 treatment hours; water residue - 100% in 6 treatment hours; soil contamination (COT degradation) - 50.3% in 12 treatment hours. AOP were effective in dealing with petroleum residues thus revealing themselves to be a promising treatment alternative / A ind?stria de petr?leo lida com problemas de dif?cil solu??o em rela??o ?s atividades voltadas para a prote??o ambiental, devido ? gera??o de res?duos de diversos tipos e n?veis de periculosidade. A contamina??o do solo por compostos de fase l?quida n?o aquosa, especificamente os hidrocarbonetos de petr?leo tem sido motivo de preocupa??o, principalmente os arom?ticos e poliarom?ticos, apresentam risco ? sa?de humana devido a seu car?ter carcinog?nico e mutag?nico. Os Processos Oxidativos Avan?ados (POA) s?o tecnologias eficientes para destrui??o de compostos org?nicos de dif?cil degrada??o biol?gica e, muitas vezes, presentes em baixas concentra??es. Podem ser consideradas tecnologias limpas, pois n?o h? a forma??o de subprodutos s?lidos e nem a transfer?ncia de fase dos poluentes. O objetivo desse trabalho foi estudar a degrada??o de res?duos da ind?stria de petr?leo, por Processos Oxidativos Avan?ados. Foram realizados tratamentos de borra de petr?leo, solo contaminado com petr?leo e ?gua de produ??o de petr?leo alcan?ando uma degrada??o de Hidrocarbonetos Polic?clicos Arom?ticos (HPA) de 100 % em 96 horas de tratamento para a borra, 100% em 6 horas de tratamento para ?gua de produ??o de petr?leo e uma degrada??o de Carbono Org?nico Total (COT) de 50,3% em 12 horas de tratamento para o solo contaminado com petr?leo. Os POA foram eficientes no tratamento de res?duos de petr?leo apresentando-se como uma alternativa promissora no tratamento desses res?duos