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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Processos oxidativos com hidroperóxidos, persulfatos ou perácidos, catalisados por espécies de cobre e de ferro com potencial aplicação em química ambiental / Oxidation processes with hydroperoxides, persulphates or peracids catalyzed by copper and iron species with potential application in environmental chemistry

Almeida Filho, Saulo Afonso de 19 June 2015 (has links)
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.
2

Processos oxidativos com hidroperóxidos, persulfatos ou perácidos, catalisados por espécies de cobre e de ferro com potencial aplicação em química ambiental / Oxidation processes with hydroperoxides, persulphates or peracids catalyzed by copper and iron species with potential application in environmental chemistry

Saulo Afonso de Almeida Filho 19 June 2015 (has links)
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.
3

Expanze ASIO, spol. s.r.o. na Kolumbijský trh / Expansion of ASIO, Ltd. into Colombian Market

Juránek, Oldřich January 2011 (has links)
Final thesis is focused on an entrance into an international market by company ASIO, Ltd. specialized on the field of water-management. The thesis is based on close analysis of Colombian market. The thesis is consisted of theoretical platform, analysis of macro- environments, segmentation of market, analysis of competitiveness, analysis of norms focused on water use and liquid waste and the proposed solution the company entered the Colombian market.
4

Propuesta de mejoramiento integral para el tratamiento y uso de aguas residuales para reducir la contaminación proveniente de PTAR “El Pedregal”, Chincha / Proposal for a comprehensive improvement for the treatment and use of wastewater to reduce pollution from the WWTP "El Pedregal" in Chincha

Aquino Lujan, Karlo Daniel, Barrientos Palomino, Jerry Eliseo 12 February 2022 (has links)
El presente trabajo de investigación es una propuesta de solución para el mal funcionamiento de la planta de tratamiento de agua residual denominada “El Pedregal”, localizada en el departamento de Ica, provincia de Chincha. Según análisis hechos por el ANA (Autoridad Nacional del Agua), la PTAR (Planta de Tratamiento de Aguas Residuales) “El Pedregal” no cumple con los parámetros de agua saliente según la norma OS 090. Por esta razón se tendrá que identificar los principales causantes del mal funcionamiento, además de plantear soluciones efectivas y que estén en el alcance de la empresa encargada de la planta “SEMAPACH S.A” (SERVICIO MUNICIPAL DE AGUA POTABLE Y ALCANTARILLADO DE CHINCHA S.A.). Uno de los principales problemas en la PTAR es su incapacidad actual de captación de agua, siendo insuficiente para la cantidad que recibe. “El Pedregal” es abastecido por 4 distritos de Chincha y abastece de agua tratada para riego a parte del distrito de Chincha Alta. Es por esto que, se plantearon propuestas de solución a esta contingencia para trasladar una proporción del agua residual a una nueva planta de tratamiento. Otro problema que se presenta la deficiente filtración del ingreso de materiales de gran tamaño a la planta, influyendo negativamente en el rendimiento y provocando obstrucciones en algunas zonas de la planta. Se plantearon propuestas con el diseño de algunas obras de arte que ayuden a disminuir el ingreso de estos materiales. Asimismo, se presentó un diseño para la construcción de un cerco perimétrico que no permita el ingreso de personas y agentes externos que puedan convertir la planta en un foco infeccioso. Se identificó que la PTAR no contaba con personal operacional y de mantenimiento, esto provocó que el ingreso de materiales de gran dimensión u otros factores externos deterioren la estructura de la PTAR, afectando su rendimiento y funcionalidad. Además, se detectó que el canal que transporta el agua desde la salida de la PTAR no soporta esta cantidad de agua. Es por ello que se diseñaran alternativas que cumplan la correcta condición de caudal, que sean económicas y sustentables. Todas las propuestas serán evaluadas y se elegirán las que obtengan mejores resultados para combinarlos en un aporte conjunto que cumpla con los objetivos planteados y que de la mejor solución integral del problema. Por lo antes mencionado, se propuso contemplar planes de gestión operacional, de limpieza y mantenimiento, añadiendo la implementación diseños, técnicas y metodologías que mejoren la productividad y eficiencia del agua tratada. Finalmente, solucionando los puntos ya explicados se espera que el agua tratada saliente de la PTAR cumpla con los parámetros establecidos por la norma para su correcto uso de riesgo y así poder disminuir la contaminación ambiental que emite la planta. / The present research work is a proposed solution to the malfunctioning of the wastewater treatment plant called "El Pedregal", located in the department of Ica, province of Chincha. According to the analyses carried out by ANA (National Water Authority), the "El Pedregal" WWTP (Wastewater Treatment Plant) does not comply with the parameters of the output water according to the OS 090 standard. Therefore, it will be necessary to identify the main causes of the malfunctioning, as well as to propose effective solutions that are within the reach of the company in charge of the plant "SEMAPACH S.A." (SERVICIO MUNICIPAL DE AGUA POTABLE Y ALCANTARILLADO DE CHINCHA S.A.). One of the main problems of the WWTP is its current inability to capture water, being insufficient for the amount it receives. "El Pedregal" is supplied by 4 districts of Chincha and supplies treated water for irrigation to part of the district of Chincha Alta. Therefore, it was proposed as a solution to this contingency to transfer part of the wastewater to a new treatment plant. Another problem is the poor filtration of large materials entering the plant, which has a negative impact on performance and causes clogging in some areas of the plant. The design of some artwork was proposed to help reduce the entry of these materials. A design was also presented for the construction of a perimeter fence to prevent the entry of people and external agents that could turn the plant into an infectious focus. It was identified that the WWTP did not have operation and maintenance personnel, which caused the entry of large materials or other external factors to deteriorate the structure of the WWTP, affecting its performance and functionality. In addition, it was detected that the channel that transports water from the WWTP outlet does not support this amount of water. Therefore, alternatives will be designed to meet the correct flow conditions, which are economical and sustainable. All proposals will be evaluated and those with the best results will be chosen to combine them into a joint contribution that will comply the proposed objectives and provide the best integral solution to the problem. For the above, it was proposed to contemplate operational management, cleaning and maintenance plans, adding the implementation of designs, techniques and methodologies that improve the productivity and efficiency of treated water. Finally, by solving the points already addressed, it is expected that the treated water leaving the WWTP will comply with the parameters established by the standard for its correct risk use and thus be able to reduce the environmental pollution emitted by the plant. / Tesis

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