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@MastersThesis{Souza:2016:EfAdZi,
               author = "Souza, Amanda Cassiano de",
                title = "Efeito da adi{\c{c}}{\~a}o da zirc{\^o}nia em aluminas 
                         empregadas como suporte de catalisadores",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2016",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2016-05-25",
             keywords = "alumina, {\'o}xido de zirc{\^o}nio, catalisadores, 
                         propuls{\~a}o espacial, refino de petr{\'o}leo, zirconium oxide, 
                         catalyst, space propulsion, petroleum refining.",
             abstract = "Na busca pelo aumento do desempenho de rea{\c{c}}{\~o}es 
                         catal{\'{\i}}ticas heterog{\^e}neas, compostos contendo 
                         elementos dopantes s{\~a}o adicionados a suportes e 
                         catalisadores, alterando suas propriedades morfol{\'o}gicas, 
                         mec{\^a}nicas e texturais. Conforme citado em in{\'u}meras 
                         refer{\^e}ncias bibliogr{\'a}ficas, a adi{\c{c}}{\~a}o de 
                         {\'o}xido de zirc{\^o}nio em alguns suportes de catalisadores 
                         pode alterar as suas propriedades, sobretudo a acidez superficial 
                         desses materiais. Neste trabalho, buscou-se avaliar a 
                         influ{\^e}ncia da presen{\c{c}}a do {\'o}xido de zirc{\^o}nio 
                         na alumina, adicionando este elemento antes da etapa de 
                         forma{\c{c}}{\~a}o do seu hidr{\'o}xido precursor ou por 
                         impregna{\c{c}}{\~a}o da alumina, ap{\'o}s 
                         calcina{\c{c}}{\~a}o do seu composto precursor. As aluminas 
                         modificadas em sua origem e os catalisadores obtidos ap{\'o}s 
                         impregna{\c{c}}{\~a}o de fases ativas foram avaliadas em 
                         rea{\c{c}}{\~o}es catal{\'{\i}}ticas heterog{\^e}neas 
                         aplicadas. Na propuls{\~a}o espacial, al{\'e}m dos aspectos 
                         mec{\^a}nicos e t{\'e}rmicos, o poss{\'{\i}}vel efeito do 
                         {\'o}xido de zirc{\^o}nio na acidez da matriz alumina foi 
                         avaliado na rea{\c{c}}{\~a}o de decomposi{\c{c}}{\~a}o da 
                         am{\^o}nia. Este g{\'a}s {\'e} formado durante a 
                         decomposi{\c{c}}{\~a}o catal{\'{\i}}tica da hidrazina no 
                         decorrer do acionamento dos propulsores de controle de {\'o}rbita 
                         e atitude de sat{\'e}lites. Sendo esta rea{\c{c}}{\~a}o de 
                         decomposi{\c{c}}{\~a}o endot{\'e}rmica, o seu controle pode 
                         reduzir a temperatura de opera{\c{c}}{\~a}o do propulsor, 
                         aumentando a vida {\'u}til do catalisador no sat{\'e}lite. No 
                         refino de petr{\'o}leo, procurou-se avaliar o efeito do 
                         {\'o}xido de zirc{\^o}nio n{\~a}o somente na acidez da alumina, 
                         mas tamb{\'e}m na atividade e seletividade dos catalisadores, 
                         obtidos a partir desse suporte, na rea{\c{c}}{\~a}o de 
                         hidrodessulfuriza{\c{c}}{\~a}o (HDS). As aluminas foram 
                         preparadas a partir de seu hidr{\'o}xido de alum{\'{\i}}nio. 
                         Este composto precursor foi ent{\~a}o moldado e, posteriormente 
                         submetido a tratamentos t{\'e}rmicos para sua 
                         transforma{\c{c}}{\~a}o em alumina ativa ou de 
                         transi{\c{c}}{\~a}o. A incorpora{\c{c}}{\~a}o da zirc{\^o}nia 
                         ocorreu de duas diferentes formas. Na primeira, antes da etapa de 
                         forma{\c{c}}{\~a}o do hidr{\'o}xido de alum{\'{\i}}nio e na 
                         segunda, por impregna{\c{c}}{\~a}o incipiente, ap{\'o}s a 
                         obten{\c{c}}{\~a}o da alumina. A prepara{\c{c}}{\~a}o dos 
                         catalisadores tamb{\'e}m foi realizada com aux{\'{\i}}lio da 
                         t{\'e}cnica de impregna{\c{c}}{\~a}o incipiente dos suportes. 
                         Os metais selecionados para avalia{\c{c}}{\~a}o em 
                         rea{\c{c}}{\~o}es do refino foram o molibd{\^e}nio (Mo) e o 
                         n{\'{\i}}quel (Ni), elementos mais utilizados em catalisadores 
                         comerciais. Os materiais preparados neste trabalho foram 
                         caracterizados por in{\'u}meras t{\'e}cnicas, entre elas 
                         volumetria de N\$_{2}\$ (BET), difratometria de raios X (DRX), 
                         dinamometria, quimissor{\c{c}}{\~a}o com mol{\'e}culas sonda 
                         (TPD) e espectroscopia de infravermelho com transformada de 
                         Fourier (FTIR). As aluminas foram avaliadas em uma unidade 
                         catal{\'{\i}}tica de bancada na rea{\c{c}}{\~a}o de 
                         decomposi{\c{c}}{\~a}o da NH\$_{3}\$, etapa realizada no 
                         Laborat{\'o}rio Associado de Combust{\~a}o e Propuls{\~a}o 
                         (LCP) do INPE. Os catalisadores impregnados com os metais Ni e Mo 
                         foram avaliados na rea{\c{c}}{\~a}o de 
                         hidrodessulfuriza{\c{c}}{\~a}o (HDS) do dibenzotiofeno (DBT), em 
                         uma unidade catal{\'{\i}}tica de alta press{\~a}o de bancada 
                         (UHP), etapa conduzida no Laborat{\'o}rio de Cat{\'a}lise 
                         (LABCAT) da UNIVAP. ABSTRACT: In order to increase performance of 
                         heterogeneous catalytic reactions, compounds containing doping 
                         elements are added to supports and catalysts, altering their 
                         morphological, mechanical, and textural properties. As mentioned 
                         in several literature references, addition of zirconium oxide in 
                         some catalyst supports can alter their properties, mainly 
                         regarding surface acidity of such materials. This work had the 
                         objective of evaluating the influence of zirconium oxide in 
                         alumina, adding this element before the formation step of its 
                         precursor hydroxide or by alumina impregnation, after calcination 
                         of its precursor compound. Modified aluminas in their origin, as 
                         well as catalysts obtained after impregnation of active phases, 
                         were evaluated in applied heterogeneous catalytic reactions. 
                         Besides mechanical and thermal aspects of space propulsion, a 
                         possible effect of zirconium oxide in the acidity of alumina 
                         matrix was evaluated regarding the ammonium decomposition 
                         reaction. This gas is formed from hydrazine catalytic 
                         decomposition throughout start up of satellites for orbit control 
                         and attitude. Since it is an endothermic decomposition reaction, 
                         its control may reduce the thruster operational temperature, 
                         increasing the catalyst useful life in the satellite. The effect 
                         of zirconium oxide was evaluated in the case of petroleum 
                         refining, not only regarding alumina acidity but also in catalyst 
                         activity and selectivity, which are obtained from this support in 
                         the hydrodesulphurization reaction (HDS). Aluminas were prepared 
                         by employing aluminum hydroxide. This precursor compound was then 
                         molded and later submitted to thermal treatments for its 
                         transformation into active or transition alumina. Zircon 
                         incorporation occurred through two manners. In the first case, it 
                         occurred in the step of aluminum hydroxide formation, and in the 
                         second case it happened by incipient impregnation, after alumina 
                         obtainment. Catalyst preparation was also done by using the 
                         incipient impregnation technique for supports. Molybdenum (Mo) and 
                         nickel (Ni) were metals selected for evaluation of refining 
                         reactions, since they are the most common elements used in 
                         commercial catalysts. Materials prepared in this study were 
                         characterized by several techniques, such as N\$_{2}\$ Volumetry 
                         (BET), X-Ray Diffractometry (DRX), dynamometry, Chemisorption with 
                         probe molecules (TPD), and Fourier Transform Infrared Spectroscopy 
                         (FTIR). Aluminas were evaluated by employing a bench catalytic 
                         unit during the NH\$_{3}\$ decomposition reaction, which was 
                         accomplished at the Combustion and Propulsion Associated 
                         Laboratory (LCP) from INPE. Impregnated catalysts with Ni and Mo 
                         metals were evaluated in the hydrodesulphurization reaction (HDS) 
                         of dibenzothiophene (DBT), by employing a high pressure catalytic 
                         bench unit (UHP). This step was conducted at UNIVAP Catalysis 
                         Laboratory (LABCAT).",
            committee = "Nono, Maria do Carmo de Andrade (presidente/orientadora) and 
                         Rodrigues, Jos{\'e} Augusto Jorge (orientador) and Soares Neto, 
                         Tur{\'{\i}}bio Gomes and Ferreira, Marco Aur{\'e}lio",
           copyholder = "SID/SCD",
         englishtitle = "Effect of addition zirconia in the aluminas employed as catalyst 
                         support",
             language = "pt",
                pages = "106",
                  ibi = "8JMKD3MGP3W34P/3LLMKHE",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3LLMKHE",
           targetfile = "publicacao.pdf",
        urlaccessdate = "25 nov. 2020"
}


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