Orientador: Claudio Airoldi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-23T02:01:02Z (GMT). No. of bitstreams: 1 MeloJunior_MauricioAlvesde_D.pdf: 8850225 bytes, checksum: 8531789c5f9acab757429aa59582c7d6 (MD5) Previous issue date: 2013 / Resumo: Foram sintetizadas sílicas mesoporosas híbridas a partir da funcionalização da SBA-15 e filossilicatos de cobalto e níquel com macrociclos orgânicos contendo sítios básicos para a sorção dos íons metálicos tóxicos Pb, Cd e Cu. A SBA-15 e o filossilicatos de magnésio também foram modificados com cadeias orgânicas contendo diferentes quantidades de átomos de enxofre para serem aplicados na sorção de íons complexos de ouro e de metais do grupo da platina com o intuito de otimizar as condições adotadas para a extração destes metais preciosos de seus minérios. Os materiais contendo macrociclos orgânicos foram formados a partir de sucessivas reações nas superfícies com diferentes moléculas orgânicas para conter os centros básicos nitrogênio, oxigênio e enxofre. As técnicas de caracterização confirmaram as formações das estruturas mesoporosas e lamelares, mostrando a presença de cadeias orgânicas pendentes contendo os grupos funcionais de interesse. Os híbridos funcionalizados com macrociclos apresentaram-se efetivos nas sorções dos metais tóxicos, com alta capacidade para o íon Pb quando estão funcionalizados com macrociclos contendo enxofre. Enquanto que, no geral, as capacidades de sorção de todos os materiais tornaram-se maiores com o aumento das quantidades de centros básicos. Estas capacidades de sorção ainda sofrem um aumento após a formação dos macrociclos. As sorções dos complexos de metais preciosos foram efetivas em todos os casos, com destaque para tetracloroaurato e tetracloropaladato, que apresentaram altos valores de sorção. Ótimos valores também foram obtidos na sorção do complexo aurotiossulfato com o filossilicato de magnésio funcionalizado com grupos tiol. As titulações calorimétricas dos metais tóxicos com as matrizes contendo macrociclos orgânicos indicaram processos favoráveis de interação dos sítios básicos com os cátions em solução aquosa, devido a valores negativos de energia de Gibbs, em um processo espontâneo, e valores positivos de entropia. Os valores de entalpia mostram que todas as interações metais/centros básicos na interface sólido/líquido são exotérmicas / Abstract: This thesis reports the syntheses of hybrid mesoporous sílicas, through the functionalization of SBA-15, and cobalt and nickel phyllosilicates functionalized with organic macrocycles containing basic sites for the sorption of the toxic metallic ions Pb, Cd and Cu. SBA-15 and magnesium phyllosilicates were also modified with organic chains containing different amounts of sulfur atoms to be applied to the sorption of complex ions of gold and platinum group metals. This is done in the aim of optimizing the conditions adopted in the extraction of these precious metals from their ores. The materials with pendant organic macrocycles were formed through successive reactions on the surfaces with different organic molecules possessing nitrogen, oxygen and sulfur basic centers. The characterization techniques confirmed the formation of mesoporous and layered structures, showing the presence of pendant organic chains with the desired functional groups. The hybrids functionalized with macrocycles were effective in the sorption of toxic metals, with high sorption capacities for Pb when the solids are functionalized with macrocycles containing sulfur atoms. Whereas the sorption capacities of all materials were improved with the increase of basic centers amounts. These sorption capacities were even improved after the macrocycles formation. The sorption of precious metals complexes were effective in all cases, especially for tetrachloroaurate and tetrachloropalladate, which presented high sorption values. Exceptional values were also acquired in the sorption of aurothiosulfate complex by the magnesium phyllosilicate functionalized with thiol groups. The calorimetric titrations of toxic metals with the matrices containing organic macrocycles indicated favorable processes for the interaction between the basic centers and the cations in aqueous solution, due to negative values of Gibbs energy, in a spontaneous process. The results also indicated positive values of entropy. The values of enthalpy showed that all the metal/basic centers interactions at the solid/liquid interface are exothermic / Doutorado / Quimica Inorganica / Doutor em Ciências

Orientador: Claudio Airoldi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T09:24:05Z (GMT). No. of bitstreams: 1 Oliveira_VaeudoValdimiro_D.pdf: 4127433 bytes, checksum: 44acdbe58b130ca68a90c55fc6bf59a7 (MD5) Previous issue date: 2012 / Resumo: Na presente investigação foram sintetizados os híbridos inorgânico-orgânicos micro/mesoestruturados: a) silicato lamelar do tipo kanemita sódica, b) sua forma quimicamente modificada com cobre e c) sílica mesoporosa SBA-16. A combinação dos reagentes Na2SiO3/NaOH/etanol e Na2SiO3/NaOH/Cu(NO3)2/etanol propiciaram a obtenção de kanemita sódica e sua forma contendo o cobre incorporado na estrutura inorgânica, através da substituição isomórfica do silício nas razões molares Si/Cu = 50, 100 e 200. Para as sílicas mesoporosas foram usados sistemas formados por copolímeros F127/TEOS/H2O, F127/TEOS/etanol/H2O e F127/TEOS/butanol/H2O em meio ácido. Os materiais organofuncionalizados previamente intercalado com dimetilsulfóxido (DMSO) e etilenodiamina (EN) formam os sólidos lamelares Na-KN-DMSO, Na-KN-EN e Cu-KN-EN, através do processo de pós-síntese com o agente sililante 3-iodopropiltrimetoxissilano, que reagiu subsequentemente com dietil iminodiacetato e benzidina, formando os híbridos mesoporosos. Os híbridos lamelares foram aplicados na sorção de metais e corantes em soluções aquosas. Dentre os cátions bário, cobalto e cobre, o cobre foi mais facilmente sorvido em Na-KN-EN quando comparado com Na-KN-DMSO. No caso dos corantes verde brilhante e azul reativo 15, o primeiro foi também mais eficiente na sorção. No processo de liberação de fármacos amoxicilina e omeprazol foram utilizados os híbridos mesoporosos. Os dados de liberação mostram que o primeiro fármaco apresentou uma cinética de liberação satisfatória no fluido intestinal simulado (FIS), enquanto que o omeprazol liberou em maior quantidade no fluido gástrico simulado (FGS) / Abstract: The present investigation deals with the syntheses of inorganic-organic nano/mesostrutered hybrids: a) sodic lamellar silicate kanemite, b) its chemically modified form with copper and c) SBA-16 mesoporous silicas. The reagents combination Na2SiO3/NaOH/ethanol and Na2SiO3/NaOH/Cu(NO3)2/ethanol enabled to obtain sodic kanemite and its synthesized form containing incorporated copper in the inorganic structure, through the isomorphic substitution of silicon using the molar ratio Si/Cu = 50, 100 and 200. For mesoporous silicas the copolymers F127/TEOS/H2O, F127/TEOS/ethanol/H2O and F127/TEOS/butanol/H2O in acidic condition were used. The synthesized organofunctionalized materials were previously intercalated with dimethylsulfoxide (DMSO) and ethylenediamine (EN) in the Na-KN-DMSO, Na-KN-EN and Cu-KN-EM lamellar solids, through the post-synthesis process with the silylating agent 3-iodopropyltrimethoxysilane, which subsequently reacted with diethyl iminodiacetate and benzidine. The lamellar hybrids were applied for cation and dye sorption processes. Among barium, cobalt and copper, the last cation was more favorable sorbed in Na-KN-EN, when compared with Na-KN-DMSO. In case of brilliant green and reactive blue 15 dyes, the first one was also more efficient in sorption. The controlled drug delivery process, amoxicillin and omeprazole were applied with mesoporous hybrid systems. The delivery data demonstrated that the first drug presented a satisfactory kinetic in the simulated intestinal fluid (SIF), while omeprazole presented high amount in the simulated gastric fluid (SGF) / Doutorado / Quimica Inorganica / Doutor em Ciências

Malgré ses avantages économiques et environnementaux, le procédé de reformage à sec du méthane sur des catalyseurs au nickel supporté se heurte encore à des problèmes de frittage de la phase active (un métal de transition) et de dépôt de carbone, ce qui entraîne une diminution de l'activité catalytique. Cette thèse porte sur l'étude de l'effet de confinement du nickel dans des catalyseurs à base de silice mésoporeuse pour la production de gaz de synthèse par reformage du méthane par le CO2. Dans cette étude, les échantillons ont été caractérisés par physisorption de N2, DRX, MET/MEB, RTP, et, en plus, par Raman, SPX, HTP/SM, ATG/SM pour les catalyseurs après test catalytique. Les résultats montrent qu'un support mésoporeux bien structuré ayant une grande surface spécifique et un grand volume poreux est important pour une meilleure dispersion et stabilisation de la phase active à l'intérieur de la porosité. La silice mésoporeuse de SBA-15 (préparée en grande quantité), composée de grains allongés, semble être appropriée pour atteindre cet objectif. Il est de plus démontré que la formation de petites particules bien confinées à l'intérieur des pores favorise la résistance au dépôt de carbone. Ceci peut être obtenu en imposant un traitement hydrothermal au support, en utilisant la méthode deux solvants pour le dépôt de Ni, en passant à une réduction directe des échantillons non calcinés, en ajoutant du Rh en faibles quantités ou en utilisant du Ce comme promoteur, à condition que le Ni et Ce soient en interaction. / Although economically and environmentally advantageous, the methane dry reforming process using supported nickel based catalysts still faces problems of active phase (a transition metal) sintering and of carbon deposition, which result in catalytic activity loss. This thesis is focused on the study of the confinement effect of nickel in mesoporous silica-based catalysts for syngas production by reforming of methane with CO2. In this study, the samples were characterized by N2 sorption, XRD, TEM/SEM, TPR, in addition to Raman, XPS, TPH/MS, TGA/MS for the spent catalysts. The results indicate that a well-structured mesoporous support with high surface area and large pore volume is important for better dispersion and stabilization of the active phase inside the porosity. The mesoporous SBA-15 silica support (prepared in large quantity), composed of elongated grains, appear to be suitable for the purpose. Moreover, it is demonstrated that the formation of small nickel particles well-confined inside the pores favors carbon resistance. This can be achieved by applying hydrothermal treatment to the support, using two solvents method for Ni deposition, using direct reduction of uncalcined samples, adding Rh in small quantities or promoting with Ce, provided that Ni and Ce are in interaction.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Sponsored by the Central Test and Evaluation Investment Program (CTEIP) under the Director of Test and Evaluation (DOT&E), the Foundation Initiative 2010 (FI 2010) project is chartered to enable interoperability among ranges, facilities, and simulations in a timely and cost-efficient manner and to foster reuse of range assets and future software systems. To achieve this vision, FI 2010 has developed and is validating a common architecture called the Test and Training Enabling Architecture (TENA), which provides for real-time software system interoperability using the TENA Middleware, as well as interfaces to existing range assets, C4ISR systems, and simulations. The TENA middleware is being developed using an iterative development process, with functionality being released in four “spirals.” The current software version, Release 3.0, was built upon previous releases and provides some key functionality enhancements to include multicast transport, vector data types and User Datagram Protocol (UDP) multicast communication support. This paper will provide detailed information on the current status of the FI 2010 project, the TENA Middleware Release 3.0, and how the TENA software has been utilized to support test and training events (e.g., Millennium Challenge 02).

Cette thèse a été réalisée dans le cadre d’une cotutelle de thèse (3 ans) Franco-Libanaise entre l’Université Pierre et Marie Curie de Paris et l’Université Libanaise de Beyrouth. Nabil Tabaja a été entièrement financé par le Groupe de Recherche MAPE (Nanosized Porous Materials, Preparation, Advanced Characterization and Environmental Applications) de Beyrouth que nous tenons à remercier. Le but de ce travail était de tester et de valoriser des catalyseurs à base d’oxydes de fer et de ferrites pour la dépollution des eaux par photocatalyse sous lumière visible puis solaire. Les catalyseurs étudiés ont été préparés en employant des silices poreuses en tant que gabarits pour obtenir majoritairement : soit des nanoparticules, NP, d’oxydes de fer ayant cristallisé à l’intérieur des pores des silices (INTERNES, répliquées), soit des nanoparticules ayant cristallisé à l’extérieur des grains de silice et formées lors des traitements d’activation thermiques (EXTERNES). Nous avons employées des techniques faciles à transférer pour obtenir les silices (Chapitre 1). Notre objectif à ce niveau était d’obtenir plus de 50g d’au moins six silices ayant des diamètres de mésopores différents. La variation de ces diamètres s’accompagne de modifications des connections entre les mésopores principaux et des propriétés des surfaces des silices. Différents sels précurseurs de fer (chlorure, nitrate) ou des mélanges de métaux ont été déposées sur les différentes silices obtenues par des techniques de dépôt de type deux solvants (2S). Les échantillons ont été traités thermiquement à 700°C sous air pour obtenir des nanoparticules d’oxydes (Chapitre 2). Nous montrons que, si le diamètre des NP nanorépliquées est en général proche du diamètre des pores des silices initiales, les formes et la dispersion des nanoparticules internes dans les grains de silice dépendent de différents facteurs expérimentaux, des sels précurseurs, des solvants et du type de silice sélectionnée. Nous montrons également que la formation des particules externes est associée au traitement thermique imposé et peut être favorisée en choisissant le bon solvant et le bon sel précurseur pour une silice déterminée. Des premiers tests ayant démontrés un taux de lixiviation important dans le cas de catalyseur au fer, nous avons testé des ferrites de différentes compositions (cations (II) de différentes électronégativités, Ni(II), Co(II), Cd(II), Zn(II) ; cation (III), Cr(III)). Afin de comparer la réactivité catalytique des catalyseurs, deux types de réactions sont introduites successivement. Le premier type de réaction, l’oxydation photocatalytique du méthanol et du formaldéhyde, a été employé à titre fondamental. Dans ce cas, notre objectif était d’étudier la sélectivité de la réaction et d’identifier de façon inambigue quelles nanoparticules présentes dans la formulation des catalyseurs permettent, partant d’une espèce à un seul carbone, d’obtenir des produits à 2 ou plus atomes de carbone (Chapitre III). La seconde réaction, l’oxydation photocatalytique d’un pesticide, a été employée pour démontrer que les catalyseurs peuvent être utiles à titre appliqué. Le pesticide sélectionné a été le carbendazime (Chapitre IV) dont nous avons suivi la décomposition. Ces études n’ont été possibles que grâce à l’emploi de techniques de caractérisation avancées, de type TOC et GC-MS. Les meilleures activités catalytiques ont été analysées en fonction de la présence d’une majorité de NP internes et/ou externes et d’autres espèces plus dispersées et non visibles par DRX. / This thesis was carried out as part of a Franco-Lebanese collaboration thesis (3 years) between the University of Pierre et Marie Curie in Paris and the Lebanese University in Beirut. Nabil Tabaja was fully funded by the Research Group MAPE (nanosized Porous Materials, Preparation, Advanced Characterization and Environmental Applications) Beirut that we thank.The purpose of this study was to test and develop catalysts based on iron oxides and ferrites for decontamination of water by photocatalysis under visible and sunlight. The catalysts studied were prepared by using porous silica as templates to obtain predominantly either nanoparticles, NP, iron oxides having crystallized within the pores of the silica (INTERNAL, replicated), or nanoparticles having crystallized outside the silica grains formed and during the thermal activation treatments (external). We employed techniques easily transferable to obtain silicas (Chapter 1). Our goal at this level was more than 50 grams of at least six silicas having different diameters of mesopores. The change in these diameters is accompanied by changes in connections between major mesoporous silicas and the properties of surfaces. Various iron precursor salts (chloride or nitrate) or metal mixtures were deposited on the various silicas obtained by the two solvents techniques (2S). The samples were calcined at 700 ° C in air to obtain oxide nanoparticles (Chapter 2). We show that, if the diameter of NP nanoreplicated is generally close to the pore diameter of the initial silicas, and forms the dispersion of nanoparticles in the inner silica grain depends on various experimental factors of the precursor salts, solvents and the type of the selected silica. We also show that the formation of particles is associated with the external heat treatment can be promoted and imposed by choosing the right solvent and the right precursor salt for a specific silica. Initial tests have demonstrated an important release rate in the case of iron catalyst, we tested different compositions ferrites ((II) cations of different electronegativities, Ni (II), Co (II), Cd (II), Zn (II) cation (III), Cr (III)). In order to compare the catalytic activity of the catalysts, two types of reactions are successively introduced. The first type of reaction, the photocatalytic oxidation of methanol and formaldehyde was employed as fundamental. In this case, our objective was to study the selectivity of the reaction and identify what way inambigue nanoparticles in the formulation of catalysts allow, starting from a species to a single carbon, to obtain products with 2 or more carbon atoms (Chapter III). The second reaction, the photocatalytic oxidation of a pesticide, was used to demonstrate that the catalysts may be useful as applied. The pesticide was selected carbendazim (Chapter IV) which we have followed the breakdown. These studies have been possible thanks to the use of advanced characterization techniques, type TOC and GC-MS. The best catalytic activities were analyzed according to the presence of a majority of internal and / or external NP and other species more dispersed and invisible by XRD.

<p>The work presented in this thesis has been focus on developing the idea of mesoreactor based on mesoporous silica SBA-15. SBA-15 is a mesoporous material with highly ordered pore structure and tailorable pore sizes with narrow sizes distribution. SBA-15 has been utilized to provide reaction sites for electroless copper deposition and the support of the synthesized copper nanoparticles. Oxidation processes have been conducted in order to improve the weak ion-exchange capability of as-synthesized silica surfaces. The efficiency of oxidation processes have been studied through various oxidizing agents and time. The surface treatments of mesoporous silica have been proofed to affect the distribution of the nanoparticles. Copper nanoparticles of 5 nm with narrow size distribution have been synthesized without the use of any capping agents and are homogeneously embedded in the silica matrix.</p>

The work presented in this thesis has been focus on developing the idea of mesoreactor based on mesoporous silica SBA-15. SBA-15 is a mesoporous material with highly ordered pore structure and tailorable pore sizes with narrow sizes distribution. SBA-15 has been utilized to provide reaction sites for electroless copper deposition and the support of the synthesized copper nanoparticles. Oxidation processes have been conducted in order to improve the weak ion-exchange capability of as-synthesized silica surfaces. The efficiency of oxidation processes have been studied through various oxidizing agents and time. The surface treatments of mesoporous silica have been proofed to affect the distribution of the nanoparticles. Copper nanoparticles of 5 nm with narrow size distribution have been synthesized without the use of any capping agents and are homogeneously embedded in the silica matrix.

<p>Sammanfattning</p><p>I dagens samhälle ställs det stora krav på att ett företags IT-system skall vara tillgängligt för kommunikation. Kommunikationen kan ske inom och mellan företag. Då dessa kommunicerande aktörer kan ha olika system och arkitekturer som gör det komplicerat att kommunicera med varandra, krävs även någon applikation som hanterar detta problem. Dessa applikationer går under namnet integrationsplattformar. Då dessa plattformar fungerar som ett centralt nav i kommunikationen är det viktigt att säkerheten i dessa är av hög nivå.</p><p>Problemet är, vilka säkerhetsrisker kan tänkas dyka upp vid användandet av integrationsplattformar i ett informationssystem? Denna fråga ledde oss in på två forskningsfrågor som presenteras nedan:</p><p>• Kan denna teknik för applikationsintegration få konsekvenser för säkerheten och i så fall på vilket sätt?</p><p>• Hur ser den bakomliggande tekniken för säkerhet ut hos två viktiga integrationsplattformar på marknaden, är dessa likvärdiga så att de säkerhetsrisker som identifieras är giltiga för integrationsplattformar generellt?</p><p>Vi började med att definiera termen säkerhet utifrån tidigare kursböcker. När detta var klart kunde vi identifiera potentiella problem som företag kunde ställas inför vid implementation av integrationsplattformar. Därefter använde vi oss av Internet och olika typer av databaser och tidskrifter för att lokalisera fakta och information som behandlar integrationsplattformar för att få en bredare förståelse för hur dessa fungerar. Vi bestämde oss för att använda primärdata vid empiriinsamlingen och valde därför att genomföra intervjuer med leverantörer, tillverkare och kunder av integrationsplattformar för att kunna få olika perspektiv från hela kedjan.</p><p>En analys har gjorts av teorin och resultat av intervjun. Analysen ger ett svar på våra två forskningsfrågor utifrån våra emperiska resultat. Vi har dragit slutsatsen att det finns säkerhetsrisker med användandet av integrationsplattformar vid applikationsintegration. De säkerhetsrisker som kan dyka upp vid användandet av integrationsplattformar i ett IS är ett flertal och väldigt beroende av hur integrationsplattformens miljö är sammansatt. Vid införandet av en ny teknik finns det risk att man ärver säkerhetsproblem från den föregående tekniken.</p><p>i</p>

UCHÔA, Antonia Flávia Justino. Síntese de sílica mesoporosa SBA 15 funcionalizada para teste de sorção de metais pesados. 2011. 93 f. Dissertação (Mestrado em química)- Universidade Federal do Ceará, Fortaleza-CE, 2011. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-05-31T18:58:05Z No. of bitstreams: 1 2011_dis_afjuchoa.pdf: 3021135 bytes, checksum: 8f8b06b80d3524ad7b692c83e1473bef (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-31T23:20:34Z (GMT) No. of bitstreams: 1 2011_dis_afjuchoa.pdf: 3021135 bytes, checksum: 8f8b06b80d3524ad7b692c83e1473bef (MD5) / Made available in DSpace on 2016-05-31T23:20:34Z (GMT). No. of bitstreams: 1 2011_dis_afjuchoa.pdf: 3021135 bytes, checksum: 8f8b06b80d3524ad7b692c83e1473bef (MD5) Previous issue date: 2011 / SBA-15 Mesoporous silica functionalized with amine (– NH2) hat been prepared in this work for the purpose of the development of heavy metals adsorbents from wastewater. The functionalization with organic groups has been performed by two different methods, post-synthesis and co-condensation. In this work, the matrix was prepared by co-condensation. Two organic groups were selected to be incorporated with specific reactions sites containing amino groups, cysteine (HS–CH2–CH(NH2)–COOH) and phenylisotiocianate (C6H5–NCS). The materials were characterized by X-ray Diffraction at low angle (XRD), Scanning Electronic Microscopy (SEM), Transmission Electron Microscopy (TEM), Nuclear Magnetic Resonance Solid State (NMR), Nitrogen adsorption-desorption (BET), Thermal Analysis (TG/DTG) and Spectroscopy of the Infrared (FT-IR). The hybrid material SBA 15_NH2 exhibit BET surface area of 451 m2/g and total pore volume 0,15 cm3/g. FT-IR, NMR, TG confirmed the incorporation of organic groups, cisteine and phenylisotiocianate in the materials. The analysis indicated that all synthesized materials showed hexagonal structure, characteristic of mesoporous materials like SBA-15 with good ordering of the pores, high surface area and narrow pore size distribution. All modified samples were subjected of sorption processes of Cu+2. The maximum adsorption capacity was 21 mg/g for the material modified with phenylisotiocianate. The Langmuir isotherm model fitted well to the experimental data together of pseudo-second order model kinetic process of adsorption. The results suggest that these materials can be used as adsorbents to remove trace metal ions in contaminated aqueous systems. / Sílicas mesoporosas do tipo SBA-15 funcionalizadas com amino (–NH2) foram preparadas para o desenvolvimento de adsorventes de metais pesados em águas residuais. A funcionalização com grupos orgânicos tem sido realizada por dois métodos distintos, pós-síntese e co-condensação. Neste trabalho a matriz foi preparada por co-condensação e dois grupos orgânicos foram selecionados para serem incorporados aos sítios de grupos amino: cisteína (HS–CH2–CH(NH2)–COOH) e fenilisotiocianato (C6H5–NCS). Os materiais foram caracterizados por difração de raios X em baixo ângulo (DRX), Microscopia Eletrônica de Varredura (MEV), Microscopia Eletrônica de Transmissão (MET),RMN no estado sólido, Adsorção-dessorção de nitrogênio, análise térmica (TG/DTG) e Espectroscopia na Região do Infravermelho (FT-IR). O material híbrido SBA-15_NH2 exibiu área superficial BET de 451 m2/g e volume total de poros de 0,15 cm3/g. FT-IR, RMN no estado sólido e TG/DTG confirmaram a incorporação das cadeias orgânicas da cisteína e fenilisotiocianato nos materiais. As análises indicaram que todas as amostras sintetizadas apresentaram estrutura hexagonal, característica dos materiais mesoporosos do tipo SBA-15, com boa ordenação dos poros, elevada área superficial e estreita distribuição de tamanhos de poros. Todas as amostras modificadas foram submetidas a processos de sorção de íons Cu2+. A capacidade de adsorção máxima foi de 21 mg/g para o material modificado com fenilisotiocianato. A isoterma de Langmuir ajustou-se melhor aos dados experimentais e associado com o modelo de pseudo-segunda ordem descreveu bem o processo cinético de adsorção. Os resultados sugerem que esses materiais podem ser usados como adsorventes para remoção de íons de metais traços em sistemas aquosos contaminados.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-11-16T14:38:36Z No. of bitstreams: 1 AnneGabriellaDiasSantos_TESE.pdf: 8503584 bytes, checksum: 1f5bb2451325c80b1d0bd5f06c1791bc (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2015-11-16T14:45:28Z (GMT) No. of bitstreams: 1 AnneGabriellaDiasSantos_TESE.pdf: 8503584 bytes, checksum: 1f5bb2451325c80b1d0bd5f06c1791bc (MD5) / Made available in DSpace on 2015-11-16T14:45:28Z (GMT). No. of bitstreams: 1 AnneGabriellaDiasSantos_TESE.pdf: 8503584 bytes, checksum: 1f5bb2451325c80b1d0bd5f06c1791bc (MD5) Previous issue date: 2013-12-16 / Ag?ncia Nacional do Petr?leo, G?s Natural e Biocombust?veis - ANP / Os materiais mesoporosos v?m tendo uma aten??o especial, dentre os quais foi descoberto no final da d?cada de 90 a peneira molecular mesoporosa do tipo SBA-15. As boas caracter?sticas do SBA-15 tornam este material muito promissor na ?rea de cat?lise, no entanto, devido ? aus?ncia de s?tios ativos nativos, ele apresenta baixa atividade catal?tica. Desta forma, diferentes metais e ?xidos v?m sendo inseridos nesta peneira molecular como meio de inserir s?tios ativos e elevar a sua atividade catal?tica. Dentre os ?xidos que vem sendo pesquisados, encontra-se o ?xido de ni?bio, que apresenta fortes s?tios ?cidos e tem em abund?ncia visto que o Brasil ? o maior produtor deste min?rio. Por outro lado a produ??o de biocombust?veis vem sendo almejada, sendo necess?rio o desenvolvimento de novos catalisadores para este fim. Desta forma, o objetivo deste trabalho foi desenvolver niobiosilicatos por um novo m?todo de s?ntese para aplica??o no craqueamento do ?leo de moringa. A metodologia consistiu em inserir o ?xido de ni?bio tanto pelo processo de p?s-s?ntese usando a impregna??o via ?mida ( porcentagens de 5, 15, 25 , 30 e 35%) e por inser??o direta. Para inser??o direta foi desenvolvido um novo m?todo de ajuste de pH, sendo testado diferentes pH ( 1.4, 1.6, 2.0 e 2.2) e diferentes raz?es de Si/Nb. Os materiais foram caracterizados por diferentes t?cnicas tais como: DRX, BET, MEV, EDX, UV-vis?vel, TG/DTG, DSC, MET , Acidez por n-bulitamina e FTIR. Posteriormente parte dos catalisadores desenvolvidos pelos dois m?todos foram testado no craqueamento termocatal?tico do ?leo de moringa, sendo usado um sistema simples de destila??o. Todos os niobiosilicatos obtidos apresentaram uma estrutura altamente ordenada, tendo altas ?reas espec?ficas, boa distribui??o de di?metros de poros, al?m de apresentar uma morfologia em forma de fibras. Nos catalisadores p?s s?ntese foi observado que o ni?bio inserido encontrava-se tanto tetraedricamente como octaedricamente coordenado, demonstrando que existiam tamb?m ?xidos formados na superf?cie externa do SBA-15, j? na s?ntese direta os materiais obtidos encontram-se apenas tetraedricamente coordenados. Dentre os pH testados o material que apresentou melhores caracter?sticas foi o sintetizado no pH 2.2. A aplica??o destes materiais no craqueamento catal?tico mostrou uma maior forma??o de l?quidos org?nicos ao serem comparados com o craqueamento t?rmico, al?m de diminuir significativamente a acidez e os res?duos formados, demonstrando que o uso do catalisador aumenta tanto a convers?o como a seletividade dos produtos. / The mesoporous materials has been an special attention, among them was discovered in the 1990?s the mesoporous molecular sieve of SBA-15 type. The good features of the SBA- 15 makes this material very promising in catalysis, however, due to the absence of native active sites, it has low catalytic activity. In this way, different metals and oxides have been included in this molecular sieve as a means of introducing active sites and increase its catalytic activity. Among the oxides that are being researched, there is the niobium oxide, which presents strong acid sites and exists in abundance. Brazil is the largest producer of the mineral. On the other hand, the production of biofuels has been desired, but it requires the development of new catalysts for this purpose. The aim of this work was to develop silicate of niobium by impregnation and by new synthesis method for application in the cracking of moringa oil. The methodology consisted of inserting the niobium oxide either by postsynthesis process using wet impregnation and direct insertion. For direct insert a new method was developed for pH adjustment, being tested different pH, and the pH 2.2 was used different ratios of Si/Nb. The materials were characterized by different techniques such as: XRD, N2 adsorption, SEM, EDS, UV-visible, TG/DTG, DSC, TEM, acidity by thermodesorption of n-butilamine and FTIR. After this part of the catalysts developed by the two methods were tested in the thermocatalytic cracking of moringa oil, being used a simple distillation. All silicates of Niobium obtained showed a highly ordered structure, having high specific areas, good distribution of pore diameters, beyond present a morphology in the form of fibers. In the catalysts after synthesis was observed that the niobium inserted has so as octahedrally and tetrahedrally coordinated, demonstrating that there were also oxides formed on the external surface of SBA-15. The materials obtained in the direct synthesis are only tetrahedrally coordinated. The new synthesis method of pH adjusting by using the buffer solution for it, proved to be very efficient for the production of such materials, because the materials obtained showed characteristics and structures similar to the molecular sieve of SBA-15 type. Among the pH tested the material that presented better characteristics was synthesized at pH 2.2. The application of these materials in catalytic cracking showed a higher formation of organic liquids when compared to thermal cracking, in addition to significantly reducing the acidity and residues formed, demonstrating that the use of silicates of Niobium increases both the conversion and the selectivity of the products.