Hydrering är en viktig process för att producera produkter med önskade egenskaper samt att uppfylla de lagliga krav som existerar med avseende på miljö och hälsa. Reaktionerna som sker vid hydreringen är katalytiska vilket innebär att förstå sam utnyttja de mest lämpliga katalysatorerna är av yttersta vikt. Avsvavling (HDS) är en av de mest studerade reaktionerna medan avaromatisering (HDA) samt borttagandet av kväve (HDN) är diskuterade samt förstådda i lägre grad. Trots det är aromatiska samt kväverika föreningar naturligt förekommande i matningar till hydreringsreaktorerna där de organiska kväveföreningarna är inhibitorer. I detta arbete är målet att tillverka samt utvärdera några hydreringskatalysatorer med fokus på deras prestanda för HDA och HDN reaktionerna. Den bästa möjliga tekniken idag för tillverkningen av hydreringskatalysatorer utnyttjar kelateringsreagens vid beredningen. Detta har visat sig ha en positiv inverkan på egenskaperna och aktivteten vid hydrering för NiMo-katalysatorer. För att undersöka detta närmare har två typer av katalysatorer tillverkats, en med kelateringsreagens (typ II) och en utan (typ I). Dessa var sedan utvärderade i dess HDA och HDN aktiveter. Katalysatorerna var tillverkade samt karaktäriserade vid KTH och sedan aktiverade via sulfidering samt utvärderade vid Nynas AB. Aktiviteten för de sulfiderade katalysatorerna var utvärderade i ett surrogatsystem bestående av fenantren (PHE) som modell för aromatiska föreningar samt karbazol (CBZ) eller akridin (ACR) som modell för icke-basiskt samt basiskt organisk-kväve. Aktivitetsutvärderingen utfördes i en porlbäddreaktor där aktiviteten undersöktes vid närvarandet samt avsaknandet av de organiska kväveföreningarna. När matningen byttes, en så kallad modeswitch, ändras aktiviteten beroende på de betingelser som undersöktes. Reaktortemperaturen varierade mellan 300 °C och 320 °C vid ett konstant systemtryck på 120 barg. Katalysatornsaktivitet var positivt korrelerad med reaktortemperaturen där en lägre aktivtetuppmättes vid 300 °C jämfört med 320 °C. Det visade sig även att båda typerna av organiskt kväve påverkade aktivteten negativt vid båda undersökta temperaturerna. Utöver det så var de basiska kväveföreningarna mer inhiberande jämfört med de icke-basiska föreningarna för båda katalysatorerna. Inhiberingen orsakad av karbazol visade sig vara helt reversibel medan akridininhiberingen antydde på mer permanenta effekter för typ II katalsatorn. Dessa resultat antyder, trots de preliminära antagandena, att typ I katalysatorn var bättre än typ II katalysatorn. / Hydrotreating processes are of high importance in helping to obtain the desired characteristics of products as well as to comply with the legislation regarding health hazards and environmental pollution. Hydrotreating reactions are catalytic reactions which imply that the understanding and utilization of the most suitable catalysts is crucial. While hydrodesulfurization is a vastly studied branch of hydrotreating, hydrodearomatization (HDA), and hydrodenitrogenation (HDN) processes are less discussed and understood. However, aromatic compounds along with nitrogen-containing inhibitors are naturally present in the hydrotreater feeds. Therefore, the aim of this study was the preparation and evaluation of hydrotreating catalysts with the main focus on HDA and HDN reactions. According to the current state of the art, the utilization of chelating agents during preparation has a positive impact on the characteristics and activity of hydrotreating catalysts therefore NiMo catalysts with (Type II) and without (Type I) a chelating agent were prepared and evaluated towards HDA and HDN reactions. The catalysts were prepared and characterized at KTH and then activated (sulfided) and evaluated at Nynas AB. The activity of the sulfided catalysts was evaluated using surrogate mixture models containing phenanthrene (PHE) as an aromatic compound, and carbazole (CBZ) or acridine (ACR). The latter ones were representing two types of nitrogen-containing inhibitors, non-basic and basic. The activity testing was carried out in a trickle-bed microreactor during three-step experiments in the presence and absence of the organic nitrogen compounds (mode switches). During the mode switches the activity of the catalysts under varying conditions was investigated. The operating temperature of the reactor varied between 300 and 320°C under constant H2 pressure of 120 barg. The catalytic activity was positively correlated with temperature with the catalysts exhibiting lower activities at 300°C than at 320°C. It is noteworthy that the activity of all the catalysts was hindered by the presence of both nitrogen compounds at all temperatures with the basic nitrogen (ACR) being more inhibitory for both catalysts. CBZ inhibition to the HDA reactions showed reversibility, while ACR had a more permanent inhibiting effect in the case of the Type II catalyst. The results indicated that despite the preliminary assumptions, the Type I catalyst outperformed the Type II.

Made available in DSpace on 2016-04-28T14:58:38Z (GMT). No. of bitstreams: 1 Augusto CesarVieira Neves Junior.pdf: 2971994 bytes, checksum: e609bbbaf217d220df7b14eb6fba68bf (MD5) Previous issue date: 2009-07-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Minimally processed products are safe and ready to eat, in spite of adding value, has a short life. Edible coatings can be an important tool to ensure the quality and increase the shelf life of minimally processed products, including persimmon. The 'Mikado' variety Persimmon has astringency and need a specific astringency process to get a minimally processed product with quality. Therefore, the objective of this work was to develop and characterize the edible coatings for use in 'Mikado' minimally processed persimmon. It was necessary to determine the exposure time of the fruit to alcohol vapor until the decrease of astringency. It was performed the flowchart for the fresh-cut of persimmon evaluating the quality of the final product. Evaluations of thickness, gas permeability, mechanical properties of coatings applied were also performed. It was also verified the efficiency of use 70% alcohol (7.00 mL ?lcool.Kg-1 fruit) to reduce astringency. There were performed the following analysis: firmness, pH, total soluble solids (? Brix), total titratable acidity, total tannins and weight loss and sensory analysis during the process. These analyses were necessary to determine the time of exposure to the alcohol vapor to decrease the concentration of soluble tannic acids in fruit that it was not tasted by panelists and determine that concentration. It was evaluated persimmon storage with and without coatings. Three experiments were conducted during this work. In the first experiment, it was set up two coatings which were used in the second trial of minimally processed. It was evaluated four different types of coatings: cassava starch, sodium alginate, carboxymethyl cellulose (CMC) and bovine gelatin. In the first experiment (edible coating), it was set up two coatings which were used in the experiment of minimally processed. Four different types of coatings were evaluated: cassava starch, sodium alginate, carboxymethyl cellulose (CMC) and bovine gelatin. In the second experiment (astringency reduction) it was defined the time required to keep the fruits in alcohol atmosphere to reduce total soluble tannins tasted by panelists. The times tested were: 10 hours, 36 hours, 55 hours, 83 hours, 107 hours, 130 hours and 155 hours. It was defined a flowchart for persimmon minimally processed. The best coatings applied in minimally processed persimmon were the cassava starch and CMC. The firmness of the fruit remained until to 55 hours of exposure to alcohol vapor. Fruits were exposure to 83 hours or up caused loss firmness below that it is commercially tolerated. The astringency was not tasted by panelists from 55 hours exposure of alcohol vapor. The threshold detection of total soluble tannin in the pulp of fruit was 0.8161 ?g.100g-1. The tannins content decrease with the increasing exposure of fruit to alcohol vapor. The reduction of astringency with 70% alcohol vapor may not be the most indicated method due to high losses in this step (21.76%). The minimally processed fruits treated with CMC coating showed less dark spots in the pulp than the other treatments and all treatments were microbiological adequates. / Produtos minimamente processados s?o produtos seguros e de pronto consumo, que apesar de agregar valor, possui uma vida ?til mais reduzida. Os revestimentos comest?veis podem se constituir em importante ferramenta para garantir a qualidade e estender a vida ?til de produtos minimamente processados, entre eles, o caqui. O caqui Mikado por ser adstringente necessita de um processo adequado de destaniza??o para gerar um produto minimamente processado de qualidade. Diante disto, este trabalho teve como objetivos o desenvolvimento e caracteriza??o de revestimentos comest?veis para a utiliza??o em caqui Mikado minimamente processado, determina??o do tempo necess?rio de exposi??o ao vapor de ?lcool para que o fruto n?o apresente adstring?ncia e elabora??o de um fluxograma para o processamento m?nimo de caqui com avalia??o da qualidade do produto final. Para o desenvolvimento e caracteriza??o dos revestimentos foram realizadas avalia??es de espessura, permeabilidade gasosa, propriedades mec?nica e pr?via sensorial do caqui Mikado minimamente processado tratados com os revestimentos comest?veis. Definiram-se dois revestimentos [amido de mandioca e carboximetilcelulose (CMC)], a partir de quatro revestimentos (amido de mandioca, alginato de s?dio, CMC e gelatina bovina) para serem testados em caqui minimamente processado. Foi tamb?m avaliado o tempo de exposi??o ao vapor de ?lcool a 70% (7mL de ?lcool.Kg-1 de fruto), por meio de an?lises f?sicas, qu?micas e sensoriais. Tais analises foram necess?rias para determinar o tempo de exposi??o ao vapor de ?lcool que diminuiria a concentra??o de ?cido t?nico sol?vel nos frutos at? que este n?o fosse mais sensorialmente percept?vel, determinando esta concentra??o e verificando-se se o fruto tinha firmeza adequada ao minimamente processado. Desta forma, foi poss?vel determinar o limiar de detec??o dos taninos sol?veis (0,8161?g.100g-1) e o tempo de exposi??o ao vapor de ?lcool mais adequado para o processamento m?nimo, que provavelmente estava entre 55 e 83 horas, sendo que os tempos testados foram de: 10 horas; 36 horas; 55 horas; 83 horas; 107 horas; 130 horas; e 155 horas. A firmeza dos frutos se manteve adequada at? as 55 horas de exposi??o ao ?lcool, sendo que um tempo igual ou superior a 83 horas de exposi??o causou perda de firmeza a um n?vel abaixo do tolerado comercialmente. Por fim foi obtido um fluxograma da produ??o de caqui Mikado minimamente processado e avaliado o armazenamento com e sem revestimentos, sendo realizado para isto analises f?sicas, qu?micas, microbiol?gicas e sensoriais ao longo do per?odo de armazenamento de 10 dias. Para a realiza??o deste experimento (processamento m?nimo de caqui) utilizou-se revestimentos de amido de mandioca e de CMC, e o tempo de destaniza??o foi de 70 horas. Verificou-se que a destaniza??o neste tempo pode n?o ser a mais adequada devido ?s altas perdas verificadas nesta etapa (21,76% dos frutos n?o se mostraram adequados ao processamento m?nimo). Os frutos minimamente processados tratados com revestimento de CMC apresentaram-se com menos manchas na polpa que os demais tratamentos e todos os tratamentos mostraram-se adequados microbiologicamente.

Made available in DSpace on 2016-04-28T14:58:57Z (GMT). No. of bitstreams: 1 2006-Nilber Kenup Hernandes.pdf: 2004617 bytes, checksum: 031cfe61d7bb727196791c4404d4e145 (MD5) Previous issue date: 2006-12-12 / This study was aimed at investigating the effects of low-dose gamma irradiation on shelf-life extension and phytosanitary safety of minimally processed red beet with basis on physicochemical; microbiological; chemical and sensory analyses. The samples (Beta vulgaris ssp. vulgaris L.), Early Wonder cultivar, were cultivated in the experimental area of the Horticulture Sector of the Departamento de Fitotecnia of the Instituto de Agronomia, Universidade Federal Rural do Rio de Janeiro, Serop?dica, RJ, as part of two experiments performed during the second semester of 2005. In each experiment, 1200 plants (40 per linear meter of terrain) were sowed. Physicochemical analyses (fresh mass; length; average diameter and total soluble solids) of the edible part of the red beets (their tuberous roots) were periodically carried out in order to assess the most appropriate time for harvest by monitoring the development of the plants. Those times were found to be 104 and 73 days after transplanting, respectively. The harvested edible part of the roots were minimally processed and separated in two groups: (1) gamma irradiated (with doses of 0.5; 1.0 and 1.5 kGy) and (2) non-irradiated (control). All samples were stored at 8 ?C. Microbiological analyses were performed during the storage period (22 and 21 days, for experiments 1 and 2, respectively) in order to evaluate the phytosanitary quality of the samples (Salmonella sp.; coliforms and total count of mesophilic aerobic and lactic acid bacteria). The samples irradiated with 1.0 and 1.5 kGy were found to remain appropriate for consumption for 21 days, as compared to only 7 days for the control. Monitoring of chemical composition was also performed and included the determination of saccharose; glucose; fructose and vitamins B1 and B2. No difference was found between the concentrations of those vitamins in irradiated and control samples at the end of the storage period, whereas significant changes in sugar contents were detected independently of the dose. In addition, physicochemical analyses investigated the evolution of pH; total acidity; total soluble solids and ascorbic acid throughout storage. Samples from experiment 2 were also subjected to sensory analyses for overall appearance and aroma at 4 different post-irradiation times. The results indicated that the samples irradiated with 1.0 and 1.5 kGy remained good for consumption for 20 days. Therefore it can be concluded that the application of those doses extended the shelf life of the samples without harming their nutritional and sensory quality. Finally, the results indicate that the dose of 1.0 kGy is the most appropriate for the conservation of red beet among those tested. / O objetivo deste estudo foi avaliar, por meio de an?lises microbiol?gicas; qu?micas; f?sicoqu?micas e sensoriais, os efeitos de baixas doses de radia??o gama na extens?o da vida ?til e na garantia da seguran?a microbiol?gica da beterraba vermelha (Beta vulgaris ssp. vulgaris L.), cultivar Early Wonder minimamente processada. Dois experimentos foram realizados, em condi??es de campo, em ?rea experimental do Setor de Horticultura do Departamento de Fitotecnia do Instituto de Agronomia da UFRRJ, Serop?dica, RJ, no segundo semestre de 2005. Em cada experimento, foram transplantadas 1200 mudas (40 por metro linear de canteiro). Foram realizados ensaios f?sico-qu?micos (massa fresca; comprimento; di?metro m?dio e teor de s?lidos sol?veis totais) da parte comest?vel (por??o tuberosa) da beterraba, para avalia??o do est?gio de desenvolvimento das plantas, visando ? determina??o do ponto ideal de colheita. As beterrabas dos experimentos 1 e 2 foram colhidas 104 e 73 dias ap?s o seu transplante, respectivamente. As partes tuberosas foram minimamente processadas e separadas em 2 grupos de amostras: controle (n?o irradiadas) e irradiadas (0,5; 1,0 e 1,5 kGy), sendo que todas foram armazenadas a 8 ?C. Avalia??es realizadas ao longo do per?odo de armazenamento (22 e 21 dias, nos experimentos 1 e 2, respectivamente) permitiram monitorar a: qualidade microbiol?gica (Salmonella sp.; coliformes; contagem total de bact?rias aer?bias mes?filas e contagem de bact?rias l?ticas); a composi??o qu?mica (determina??o dos teores de: sacarose; glicose e frutose e vitaminas B1 e B2) e as propriedades f?sico-qu?micas (pH; acidez total titul?vel; teor de s?lidos sol?veis totais e teor de ?cido asc?rbico). As amostras do experimento 2 foram tamb?m submetidas a an?lises sensoriais (apar?ncia e aroma) em quatro ocasi?es ap?s a irradia??o. Os resultados das an?lises microbiol?gicas indicaram que somente as amostras irradiadas com 1,0 e 1,5 kGy mantiveram-se pr?prias para o consumo por 21 dias, enquanto que as n?o irradiadas apresentaram vida ?til inferior a 7 dias. Ao fim do per?odo de avalia??o, n?o foi observada diferen?a entre os teores das vitaminas B1 e B2 das amostras irradiadas em rela??o ?s de controle. Os teores dos a??cares, por outro lado, sofreram altera??es significativas ao longo do tempo, independentemente das doses aplicadas. Em contraste, n?o foram constatadas altera??es indesej?veis nas propriedades f?sico-qu?micas ocasionadas pela irradia??o. Os resultados das an?lises sensoriais indicaram que as amostras irradiadas com doses de 1,0 e 1,5 kGy mantiveram-se dentro dos padr?es de aceitabilidade por 20 dias. Consistentemente, verificou-se que a aplica??o dessas doses foi eficaz para estender a vida ?til, sem prejudicar a qualidade nutricional ou sensorial das amostras. Finalmente, conclui-se que a dose de 1,0 kGy mostrou-se como a mais apropriada, dentre aquelas estudadas, para a irradia??o de beterraba vermelha minimamente processada.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-03-14T12:18:08Z No. of bitstreams: 1 2017 - Gisele Lopes dos Santos.pdf: 3827549 bytes, checksum: bb5ae05f3998cf1fc3f662ddc86731d0 (MD5) / Made available in DSpace on 2018-03-14T12:18:08Z (GMT). No. of bitstreams: 1 2017 - Gisele Lopes dos Santos.pdf: 3827549 bytes, checksum: bb5ae05f3998cf1fc3f662ddc86731d0 (MD5) Previous issue date: 2017-06-01 / This work has as objective reflect on the emergence and implementation of the Minimum Curriculum (CM) in the State Education Network, specifically in the Biology discipline, in 2012, presented by the State Department of Education of the State of Rio de Janeiro (SEEDUC). From the socio-historical studies of the curriculum, it is sought to understand the elements that supported the emergence and implantation of the CM and how this proposal refines the external evaluations in the state, ENEM (National High School Exam) and SAERJ (Evaluation of Education in the State of Rio de Janeiro). This work constitutes a qualitative research, based on theoretical and methodological, based on the curricular studies dialoguing with the empirical sources constituted by the documents related to the emergence and implantation of the curriculum (information of the SEEDUC website, Resolution 4.866 of February 14, 2013, Minimum Curriculum of Biology, Earnings by Results SEEDUC) and by published articles on the subject. The initial objective is that through the interbreeding of these written sources one can construct a narrative about the minimal curriculum of the biology curricular component. From the analysis of the official documents regarding the CM, with regard to the concept of skills and competences, it is possible to note its proximity to the external evaluations, since the curriculum and other strategies created by SEEDUC aim to corroborate with the increase of the index Of State education in external evaluations such as IDEB (Indicator and Development of Basic Education). The CM of Biology presents skills and competences, which SEEDUC claims to be organized progressively in the official document - from the simplest or most concrete, towards a more complex or abstract one. However, analyzing this document, the two-month course distributed in the CM of biology, it is possible to sustain that this progression of contents does not always happen, it presents in a sparse and irregular form. In this sense, it was possible to perceive when analyzing the document of the CM of Biology that the teaching continues to be presented in a fragmented way; Hindering the student to associate what he / she learns in school with his daily life. After analyzing the CM of Biology, the idea that the meanings of the concepts of competences and abilities, although approaching the cognitive-constructivist side of Perrenoud, is also moved towards Tyler's compartamentalism, when he centralizes his questions in External evaluations, the accountability curriculum and performativity / Este trabalho tem como objetivo refletir sobre o surgimento e implanta??o do Curr?culo M?nimo (CM) na rede Estadual de Educa??o, especificamente na disciplina Biologia, em 2012, apresentado pela Secretaria de Estado de Educa??o do Estado do Rio de Janeiro (SEEDUC). A partir dos estudos s?cio-hist?ricos do curr?culo, busca-se compreender os elementos que sustentaram o surgimento e implanta??o do CM e como esta proposta se afina as avalia??es externas presentes no estado, ENEM (Exame Nacional do Ensino M?dio) e SAERJ (Sistema de Avalia??o da Educa??o do Estado do Rio de Janeiro). Este trabalho constitui uma pesquisa qualitativa, a base te?rico-metodol?gica, apoiou-se nos estudos curriculares dialogando com as fontes emp?ricas constitu?das pelos documentos relativos ao surgimento e implanta??o do curr?culo (informa??es do site da SEEDUC, Resolu??o 4.866 de 14 de fevereiro de 2013, Curr?culo M?nimo de Biologia, Bonifica??o por Resultados SEEDUC) e por artigos publicados a respeito do tema. O objetivo inicial ? que se possa atrav?s do intercruzamento destas fontes escritas construir uma narrativa a respeito do curr?culo m?nimo da componente curricular biologia. A partir da an?lise dos documentos oficiais a respeito do CM, no que se refere ao conceito de habilidades e compet?ncias, nota-se sua proximidade com as avalia??es externas, visto que o curr?culo e outras estrat?gias criadas pela SEEDUC almejam corroborar com a eleva??o do ?ndice da educa??o do Estado em avalia??es externas como o IDEB (Indicador e Desenvolvimento da Educa??o B?sica). O CM de Biologia apresenta habilidades e compet?ncias, as quais a SEEDUC argumenta estar organizada de forma progressiva no documento oficial ? da mais simples ou concreta, em dire??o a uma mais complexa ou abstrata. Todavia, analisando este documento, os bimestres letivos distribu?dos no CM de biologia, ? poss?vel sustentar que esta progress?o de conte?dos nem sempre acontece, apresenta-se de forma esparsa e irregular. Neste sentido, foi poss?vel perceber ao analisar o documento do CM de Biologia que o ensino continua a ser apresentado de forma fragmentada; obstaculizando o estudante associar o que aprende na escola com seu cotidiano. Ap?s an?lise do CM de Biologia, sustenta-se a ideia de que os sentidos dos conceitos de compet?ncias e habilidades embora se aproximem da vertente cognitivoconstrutivista, de Perrenoud, tamb?m se movimenta em dire??o ao compartamentalismo de Tyler, quando centraliza suas quest?es em avalia??es externas, no curr?culo do accountability e na performatividade.

Gas-oil obtained from bitumen contains a significant amount of impurities, which are difficult to remove using a conventional alumina supported hydrotreating catalyst. Innumerable studies have been carried out to develop a highly effective hydrotreating catalyst, and among all utilizing more advanced support is considered as a better alternative. Recently, SBA-15, which is an ordered mesoporous silica support, has received importance as a catalyst support because of its excellent textural properties. However, SBA-15 lacks surface acidity and provides very low metal-support interaction. By modifying SBA-15 with zirconia, an optimum level of surface acidity and Si-Mo interaction can be achieved. Also, by doping zirconia with SBA-15, the textural properties of zirconia can be improved. Hence, a synergistic effect can be obtained while incorporating zirconia onto SBA-15 and the resulting material Zr-SBA-15 can be used as an effective support for hydrotreating catalyst. In the present study, Zr-SBA-15 supports were prepared by the post synthesis and the direct synthesis method with different zirconia loading. Zr-SBA-15 supported NiMo catalysts were prepared by incipient wetness impregnation technique. Catalysts and supports were characterized by small angle X-ray scattering (SAXS), nitrogen adsorption/desorption (BET), powder X-ray diffraction (XRD), transmission electron spectroscopy (TEM), scanning electron microscopy (SEM), and Raman spectroscopy methods.<p> Characterization of support confirmed that the zirconia was successfully incorporated in a mesoporous SBA-15 structure without significantly changing the textural properties of SBA-15. The performance of the Zr-SBA-15 supported NiMo catalysts was evaluated based on hydrodesulfurization and hydrodenitrogenation activities exhibited during hydrotreating of heavy gas oil derived from Athabasca bitumen at industrial operating condition (temperature 375-395 °C, pressure 8.9 MPa, LHSV 1.0 hr-1 and gas/oil ratio 600 Nm3/m3). The comparison of catalytic activities showed that the NiMo catalysts supported on Zr-SBA-15, prepared by direct and post synthesis method exhibited higher hydrotreating activity compared to SBA-15 supported catalyst. NiMo catalyst supported on Zr-SBA-15 with 23 wt% of ZrO2 loading, prepared by post synthesis method showed the highest activity among all the catalysts.<p> After determining the best support, the optimum catalyst metal loadings on the Zr-SBA-15 support was found to be 17 wt% of Mo and 3.4 wt% of Ni. This catalyst also showed higher activity in mass basis for the hydrotreating of heavy gas oil compared to that of commercial hydrotreating catalyst.<p> A kinetic study was performed on the optimum NiMo/Zr-SBA-15 catalyst to predict its HDS and HDN activities while varying the parameters of temperature, liquid hourly space velocity (LHSV), pressure and gas-to-oil ratio. Rate expressions were developed using Power Law and Langmuir-Hinshelwood model to predict the behavior of both the HDS and HDN reactions. Power law models were best fit with reaction orders of 1.8 and 1.3, and activation energies of 115 kJ/mol and 121 kJ/mol, for HDS and HDN reactions, respectively. The activation energies calculated using Langmuir-Hinshelwood model considering H2S inhibition were found to be 122 kJ/mol and 138 kJ/mol, for HDS and HDN reactions, respectively.

New catalyst development for the hydrotreating process, employing functionalized mesoporous carbon (mC) support is studied. mC support was prepared by the volume templating of alkali modified SBA-15 using sucrose as the carbon source and then functionalized using nitric acid of various concentrations (upto 8M HNO3). A series of NiMo catalysts (12% Mo and 2.4% Ni) were prepared using these functionalized mC supports. The supports and catalysts were characterized by N2 physisorption, SAXS, XRD, FTIR, TGA, SEM, TEM, H2-TPR and HRTEM. SAXS results indicated mild reduction in ordered structure of mesoporous carbons after functionalization. N2 physisorption analysis indicated progressive reduction in surface area and pore volume with the increase in nitric acid concentration. Enhancement of surface functional groups and acidity after functionalization were observed through FTIR spectroscopy and Boehm titration. SEM images showed the retention of needle like morphology in all functionalized carbon supports. TEM images showed that the increase in nitric acid concentration causes excessive etching, resulting in the reduction of ordered structure of functionalized mesoporous carbons. Hydrotreating study of these NiMo/mC catalysts were carried out under industrial operating conditions in a laboratory scale trickle bed reactor using coker light gas oil derived from Athabasca bitumen as feedstock. NiMo catalyst supported on 6M acid treated mC (i.e. NiMo/mC-6M) showed the highest activity due to higher surface functional groups, higher acidity and better textural properties. The HDS and HDN activities of NiMo/mC-6M catalyst were higher than that of NiMo/ã-Al2O3 catalyst owing to lower support metal interaction (SMI), higher surface area and effective functionalization. Using the mC-6M support, NiMo catalysts with different metal loading (12 27% Mo, 2.4 to 5.4% Ni) were prepared and characterized. Hydrotreating activity study of these catalysts indicated that the catalyst with 22% Mo and 2.9% Ni loading was the optimum catalyst on 6M functionalized mC support. Higher metal loading (>22%Mo) led to excessive pore blockage and improper metal dispersion resulting in decreased activity. Kinetic study of the optimum catalyst was carried out by varying temperature (330°C to 370°C), gas-to-oil ratio (400 1000 Nm3/m3), LHSV (1.0 to 2.5 hr-1) and pressure (7.8 to 9.8 MPa) and the data was fitted by non-linear regression method using power law model. The calculated reaction orders and activation energies were 2.8, 1.5 and 189 KJ/mol, 98.9 KJ/mol for HDS and HDN, respectively. The results of HRTEM and H2-TPR indicated lower SMI in mC supported catalyst resulting in the generation of qualitatively Type-II like NiMoS phase on functionalized mC supports, which is considered to be very active for hydrotreating. The hydrotreating activity of the optimum catalyst was higher than that of commercial catalyst (supported on ã-Al2O3). Long term deactivation experiment carried out over a total period of 10 weeks confirmed the durability of NiMo/mC catalyst for the duration of operation. This study reveals the immense capability of functionalized mC supports to become the potential alternative catalyst support to conventional ã-Al2O3 for the hydrotreating of gas oil feedstocks.

Gas-oil obtained from bitumen contains a significant amount of impurities, which are difficult to remove using a conventional alumina supported hydrotreating catalyst. Innumerable studies have been carried out to develop a highly effective hydrotreating catalyst, and among all utilizing more advanced support is considered as a better alternative. Recently, SBA-15, which is an ordered mesoporous silica support, has received importance as a catalyst support because of its excellent textural properties. However, SBA-15 lacks surface acidity and provides very low metal-support interaction. By modifying SBA-15 with zirconia, an optimum level of surface acidity and Si-Mo interaction can be achieved. Also, by doping zirconia with SBA-15, the textural properties of zirconia can be improved. Hence, a synergistic effect can be obtained while incorporating zirconia onto SBA-15 and the resulting material Zr-SBA-15 can be used as an effective support for hydrotreating catalyst. In the present study, Zr-SBA-15 supports were prepared by the post synthesis and the direct synthesis method with different zirconia loading. Zr-SBA-15 supported NiMo catalysts were prepared by incipient wetness impregnation technique. Catalysts and supports were characterized by small angle X-ray scattering (SAXS), nitrogen adsorption/desorption (BET), powder X-ray diffraction (XRD), transmission electron spectroscopy (TEM), scanning electron microscopy (SEM), and Raman spectroscopy methods.<p> Characterization of support confirmed that the zirconia was successfully incorporated in a mesoporous SBA-15 structure without significantly changing the textural properties of SBA-15. The performance of the Zr-SBA-15 supported NiMo catalysts was evaluated based on hydrodesulfurization and hydrodenitrogenation activities exhibited during hydrotreating of heavy gas oil derived from Athabasca bitumen at industrial operating condition (temperature 375-395 °C, pressure 8.9 MPa, LHSV 1.0 hr-1 and gas/oil ratio 600 Nm3/m3). The comparison of catalytic activities showed that the NiMo catalysts supported on Zr-SBA-15, prepared by direct and post synthesis method exhibited higher hydrotreating activity compared to SBA-15 supported catalyst. NiMo catalyst supported on Zr-SBA-15 with 23 wt% of ZrO2 loading, prepared by post synthesis method showed the highest activity among all the catalysts.<p> After determining the best support, the optimum catalyst metal loadings on the Zr-SBA-15 support was found to be 17 wt% of Mo and 3.4 wt% of Ni. This catalyst also showed higher activity in mass basis for the hydrotreating of heavy gas oil compared to that of commercial hydrotreating catalyst.<p> A kinetic study was performed on the optimum NiMo/Zr-SBA-15 catalyst to predict its HDS and HDN activities while varying the parameters of temperature, liquid hourly space velocity (LHSV), pressure and gas-to-oil ratio. Rate expressions were developed using Power Law and Langmuir-Hinshelwood model to predict the behavior of both the HDS and HDN reactions. Power law models were best fit with reaction orders of 1.8 and 1.3, and activation energies of 115 kJ/mol and 121 kJ/mol, for HDS and HDN reactions, respectively. The activation energies calculated using Langmuir-Hinshelwood model considering H2S inhibition were found to be 122 kJ/mol and 138 kJ/mol, for HDS and HDN reactions, respectively.

New catalyst development for the hydrotreating process, employing functionalized mesoporous carbon (mC) support is studied. mC support was prepared by the volume templating of alkali modified SBA-15 using sucrose as the carbon source and then functionalized using nitric acid of various concentrations (upto 8M HNO3). A series of NiMo catalysts (12% Mo and 2.4% Ni) were prepared using these functionalized mC supports. The supports and catalysts were characterized by N2 physisorption, SAXS, XRD, FTIR, TGA, SEM, TEM, H2-TPR and HRTEM. SAXS results indicated mild reduction in ordered structure of mesoporous carbons after functionalization. N2 physisorption analysis indicated progressive reduction in surface area and pore volume with the increase in nitric acid concentration. Enhancement of surface functional groups and acidity after functionalization were observed through FTIR spectroscopy and Boehm titration. SEM images showed the retention of needle like morphology in all functionalized carbon supports. TEM images showed that the increase in nitric acid concentration causes excessive etching, resulting in the reduction of ordered structure of functionalized mesoporous carbons. Hydrotreating study of these NiMo/mC catalysts were carried out under industrial operating conditions in a laboratory scale trickle bed reactor using coker light gas oil derived from Athabasca bitumen as feedstock. NiMo catalyst supported on 6M acid treated mC (i.e. NiMo/mC-6M) showed the highest activity due to higher surface functional groups, higher acidity and better textural properties. The HDS and HDN activities of NiMo/mC-6M catalyst were higher than that of NiMo/ã-Al2O3 catalyst owing to lower support metal interaction (SMI), higher surface area and effective functionalization. Using the mC-6M support, NiMo catalysts with different metal loading (12 27% Mo, 2.4 to 5.4% Ni) were prepared and characterized. Hydrotreating activity study of these catalysts indicated that the catalyst with 22% Mo and 2.9% Ni loading was the optimum catalyst on 6M functionalized mC support. Higher metal loading (>22%Mo) led to excessive pore blockage and improper metal dispersion resulting in decreased activity. Kinetic study of the optimum catalyst was carried out by varying temperature (330°C to 370°C), gas-to-oil ratio (400 1000 Nm3/m3), LHSV (1.0 to 2.5 hr-1) and pressure (7.8 to 9.8 MPa) and the data was fitted by non-linear regression method using power law model. The calculated reaction orders and activation energies were 2.8, 1.5 and 189 KJ/mol, 98.9 KJ/mol for HDS and HDN, respectively. The results of HRTEM and H2-TPR indicated lower SMI in mC supported catalyst resulting in the generation of qualitatively Type-II like NiMoS phase on functionalized mC supports, which is considered to be very active for hydrotreating. The hydrotreating activity of the optimum catalyst was higher than that of commercial catalyst (supported on ã-Al2O3). Long term deactivation experiment carried out over a total period of 10 weeks confirmed the durability of NiMo/mC catalyst for the duration of operation. This study reveals the immense capability of functionalized mC supports to become the potential alternative catalyst support to conventional ã-Al2O3 for the hydrotreating of gas oil feedstocks.

Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-04-10T13:55:08Z No. of bitstreams: 1 BibianoMadridTese2016.pdf: 2121621 bytes, checksum: e27cdc9330322e7d6796de7bcf0c585c (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-04-10T13:55:16Z (GMT) No. of bitstreams: 1 BibianoMadridTese2016.pdf: 2121621 bytes, checksum: e27cdc9330322e7d6796de7bcf0c585c (MD5) / Made available in DSpace on 2017-04-10T13:55:16Z (GMT). No. of bitstreams: 1 BibianoMadridTese2016.pdf: 2121621 bytes, checksum: e27cdc9330322e7d6796de7bcf0c585c (MD5) Previous issue date: 2016-02-25 / The present study is composed by four papers with different aims, as follows: 1) Verify the reliability of the Wingate anaerobic test. 2) Verify the reliability of lactate minimum protocol with induction of hyperlactatemia individualized by ratings perceived exertion. 3) Verify the efficiency of a new submaximal protocol for aerobic evaluation, with workloads determination by ratings perceived exertion, denominated RPE-13, in identify the intensity of exercise associated at maximal lactate steady state and lactate minimum. 4) Verify the influence of anodal transcranial direct current stimulation on left temporal lobe in the heart rate variability and in the running of 3000 meters. The Wingate study had a sample composed by 15 cyclists that performed three Wingate tests. The lactate minimum study had a sample composed by 20 university students active physically that performed two times the test. In the study with RPE-13 the sample was formed by 11 young adults active physically that performed three tests, the RPE-13, lactate minimum and maximal lactate steady state. Yet, in the study with anodal transcranial direct current stimulation the sample was composed by 11 amateurs??? runners that performed of the 3000 meters test in two conditions, in the anodal stimulation and Sham condition (placebo). The tests of Wingate and lactate minimum showed good reliability. The RPE-13 test showed to be efficient to identify an intensity of exercise associated at maximal lactate steady state and lactate minimum. Therefore, the transcranial direct current stimulation changed the heart rate variability, increasing the chronotropic reserve and improving the performance in running of 3000 meters in mean 10 seconds. / O presente trabalho ?? composto por quatro artigos cient??ficos com diferentes objetivos, conforme a seguir: 1) Verificar a reprodutibilidade do teste anaer??bio de Wingate. 2) Verificar a reprodutibilidade do protocolo de lactato m??nimo com a indu????o a hiperlactatemia individualizada pela percep????o subjetiva de esfor??o. 3) Verificar a efici??ncia do um novo protocolo subm??ximo de avalia????o aer??bia, com cargas determinadas pela percep????o subjetiva de esfor??o, denominado RPE-13, em identificar a intensidade de exerc??cio associada ao m??ximo estado est??vel de lactato e lactato m??nimo. 4) Verificar a influ??ncia da estimula????o transcraniana por corrente cont??nua an??dica sob o lobo temporal esquerdo sobre a variabilidade da frequ??ncia card??aca e no desempenho em teste de corrida de 3000 metros. O estudo com Wingate teve uma amostra composta por 15 ciclistas que realizaram tr??s testes de Wingate. O estudo com lactato m??nimo teve uma amostra composta por 20 estudantes universit??rios fisicamente ativos que realizaram o teste duas vezes. No estudo com o protocolo RPE-13 a amostra foi formada por 11 adultos jovens fisicamente ativos que realizaram tr??s testes, o RPE-13, lactato m??nimo e m??ximo estado est??vel de lactato. J?? no estudo com estimula????o transcraniana por corrente cont??nua a amostra foi composta onze corredores recreacionais que cumpriram o teste de 3000 metros em duas condi????es, na condi????o com estimula????o an??dica e na condi????o Sham (placebo). Os testes de Wingate e lactato m??nimo apresentaram boa reprodutibilidade. O teste RPE-13 se mostrou eficiente em identificar uma intensidade de exerc??cio associada m??ximo estado est??vel de lactato e lactato m??nimo. Por sua vez, a estimula????o transcraniana por corrente cont??nua modificou a variabilidade da frequ??ncia card??aca, aumentando a reserva cronotr??pica e melhorando o desempenho do teste de corrida de 3000 metros em m??dia em 10 segundos.

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2015-10-08T22:13:49Z No. of bitstreams: 1 Disserta??o Final_Fabio Ribeiro Garcia.pdf: 1235311 bytes, checksum: 99c4c15b4044b2e3d060b0f7f4d595d4 (MD5) / Made available in DSpace on 2015-10-08T22:13:49Z (GMT). No. of bitstreams: 1 Disserta??o Final_Fabio Ribeiro Garcia.pdf: 1235311 bytes, checksum: 99c4c15b4044b2e3d060b0f7f4d595d4 (MD5) Previous issue date: 2013-05-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / bromeliad species are native to Brazil and have great potential for use as an ornamental plant, and a relevant ecological importance. Considering the devastation of the Atlantic, currently 7.3% of its original area preserved and where about 70% are endemic bromeliad is important to establish methods of propagation and ex situ conservation in order to preserve this germplasm and avoid irreversible genetic erosion. Thus, the aim of this work was to establish protocols and micropropagation in vitro conservation of A. blancheteana and A. miniata. In the first chapter, for multiplication in vitro, we used different concentrations of BAP and for rooting tested different concentrations of auxins IAA, IBA and NAA. In the second chapter we tested two protocols, was first used in MS medium supplemented with different concentrations of auxin Picloram and 2,4-D combined with BAP and the second experiment evaluated MS medium supplemented with 2,4-D or picloram in different concentrations. In the third chapter, we investigated the effect of osmotic agents, sucrose, sorbitol and mannitol in vitro conservation A. blancheteana. For the best result micropropagation for multiplication was for medium supplemented with 4.44 ?M BA. To induce somatic embryos and regeneration of the concentration of 22.5 ?M 2,4-D was the most efficient. Independent of concentration, mannitol was more efficient for in vitro conservation of A. blancheteana for 12 months. / Aechmea blancheteana (Baker) L.B. Smith e Aechmea miniata (Beer) Baker s?o esp?cies de brom?lias nativas do Brasil que possuem grande potencial para uso como planta ornamental, al?m de relevante import?ncia ecol?gica. Considerando a grande devasta??o de Mata Atl?ntica, atualmente com 7,3% de sua ?rea original preservada, onde cerca de 70% das brom?lias s?o end?micas ? importante o estabelecimento de m?todos propaga??o e conserva??o ex situ com o objetivo de preservar esse germoplasma e evitar uma eros?o gen?tica irrevers?vel. Assim, o objetivo deste trabalho estabelecer os protocolos de micropropaga??o e conserva??o in vitro de A. blancheteana e A. miniata. No primeiro cap?tulo, para a multiplica??o in vitro, foram utilizadas diferentes concentra??es de BAP e na fase de enraizamento foram testadas diferentes concentra??es das auxinas AIA, AIB e ANA. No segundo cap?tulo foram testadas a combina??o de diferentes concentra??es das auxinas Picloram e 2,4-D e da auxina 2,4-D combinada com a citocinina BAP na indu??o de embri?es som?ticos. No terceiro cap?tulo, foi avaliado o efeito dos agentes osm?ticos, sacarose, sorbitol e manitol na conserva??o in vitro de A. blancheteana. Para a micropropaga??o o melhor resultado foi obtido em meio MS suplementado com 4,44?M de BAP. Para a indu??o e regenera??o de embri?es som?ticos, a concentra??o 22,5?M de 2,4-D foi a mais eficiente. Independente da concentra??o, o manitol foi mais eficiente para a conserva??o in vitro de A. blancheteana por 12 meses.