Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-04-11T19:34:25Z No. of bitstreams: 1 JulianaElionaraBezerraCosta_TESE.pdf: 2543108 bytes, checksum: 556e8d7316f4202efa7113ded946013c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-04-12T22:40:15Z (GMT) No. of bitstreams: 1 JulianaElionaraBezerraCosta_TESE.pdf: 2543108 bytes, checksum: 556e8d7316f4202efa7113ded946013c (MD5) / Made available in DSpace on 2018-04-12T22:40:16Z (GMT). No. of bitstreams: 1 JulianaElionaraBezerraCosta_TESE.pdf: 2543108 bytes, checksum: 556e8d7316f4202efa7113ded946013c (MD5) Previous issue date: 2017-12-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Alguns res?duos, provenientes das mais variadas atividades, podem ser reaproveitados, diminuindo o efeito dos impactos ambientais ocasionados pela m? disposi??o dos mesmos no meio ambiente. Os res?duos classificados com biomassa lignocelul?sica, podem ser convertidos em produtos qu?micos e combust?veis a partir da pir?lise r?pida convencional, gerando como produto principal o bio-?leo com caracter?sticas diretamente ligadas as caracter?sticas da biomassa de origem que podem ser melhoradas a partir do uso de catalisadores. Neste trabalho foram sintetizados catalisadores do tipo ZSM-5 e HZSM-5, utilizando res?duos de p? de granito, p? de vidro, diatomita e cinza da casca do arroz como fontes alternativas e tamb?m um catalisador utilizando fonte convencional de S?lica e Alum?nio. O objetivo da s?ntese desses materiais ? utiliz?-los como catalisador na pir?lise da fibra do coco visando a obten??o de produtos com maior valor agregado, reduzindo a produ??o de compostos oxigenados. A biomassa utilizada foi caracterizada por an?lise imediata, densidade, an?lise elementar, Teor de Celulose, hemicelulose e lignina, Poder calor?fico, TG/DTG, DRX, FT-IR e FRX afim de analisar o potencial energ?tico da mesma. Os precursores de S?lica e Alum?nio foram submetidos a an?lises de FRX, DRX, e os catalisadores foram caracterizados por TG/DTG, DRX, FT-IR, MEV e BET. Nos resultados de pir?lise convencional da fibra do coco observou a grande produ??o de produtos oxigenados, a maior parte deles fen?is e nos resultados das pir?lise catal?tica foi poss?vel observar a diminui??o desses produtos, provando a efici?ncia dos catalisadores utilizados. / Some waste, from the most varied activities, can be reused, reducing the effect of these impacts, usually caused by poor disposal in the environment. The residues classified with lignocellulosic biomass can be converted into chemical products and fuels from the conventional fast pyrolysis, generating as main product the bio-oil. This generally presents some undesirable characteristics directly linked to the characteristics of the source biomass, which decrease its energy efficiency. The use of catalysts allows the reduction of these undesirable products and improves the final quality of the bio oil. As a result, ZSM-5 and HZSM-5 catalysts were synthesized using granite powder, glass powder, diatomite and rice husk ash as alternative sources of silica and aluminum; was also synthesized using a conventional silica and aluminum source, serving as a standard for the others. . The objective of the synthesis of these materials is to use them as a catalyst in the pyrolysis of coconut fiber in order to obtain products with higher added value, reducing the production of oxygenated compounds. The biomass used was characterized by immediate analysis, density, elemental analysis, cellulose content, hemicellulose and lignin, calorific power, TG / DTG, XRD, FT-IR and FRX in order to analyze the energy potential of the same. Silica and Aluminum precursors were subjected to FRX, XRD analyzes, and the catalysts were characterized by TG / DTG, DRX, FT-IR, MEV and BET. In the results of conventional pyrolysis of the coconut fiber, it was observed the great production of oxygenated products, most of them phenols and in the results of the catalytic pyrolysis it was possible to observe the decrease of these products, proving the efficiency of the catalysts used.

Made available in DSpace on 2014-12-17T14:07:15Z (GMT). No. of bitstreams: 1 MariaSBF_TESE.pdf: 2706042 bytes, checksum: e909d3cb5ee177d47cc6917725b38335 (MD5) Previous issue date: 2013-05-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In recent years, the area of advanced materials has been considerably, especially when it comes to materials for industrial use, such as is the case with structured porosity of catalysts suitable for catalytic processes. The use of catalysts combined with the fast pyrolysis process is an alternative to the oxygenate production of high added value, because, in addition to increasing the yield and quality of products, allows you to manipulate the selectivity to a product of interest, and therefore allows greater control over the characteristics of the final product. Based on these arguments, in this work were prepared titanium catalysts supported on MCM-41 for use in catalytic pyrolysis of biomass, called elephant grass. The reactions of pyrolysis of biomass were performed in a micro pyrolyzer, Py-5200, coupled to GC / MS, the company CDS Corporation, headquartered in the United States. The catalysts Ti-MCM-41 in different molar ratios were characterized by XRD, TG / DTG, FT-IR, SEM, XRF, UV-visible adsorption of nitrogen and the distribution of particle diameter and specific surface area measurement by the BET method. From the catalytic tests it was observed that the catalysts synthesized showed good results for the pyrolysis reaction.The main products were obtained a higher yield of aldehydes, ketones and furan. It was observed that the best reactivity is a direct function of the ratio Si/Ti, nature and concentration of the active species on mesoporous supports. Among the catalysts Ti-MCM-41 (molar ratio Si / Ti = 25 and 50), the ratio Si / Ti = 25 (400 ? C and 600 ? C) favored the cracking of oxygenates such as acids , aldehydes, ketones, furans and esters. Already the sample ratio Si / Ti = 50 had the highest yield of aromatic oxygenates / Nos ?ltimos anos, a ?rea de materiais tem avan?ado consideravelmente, principalmente, quando se trata de materiais para uso industrial, como ? o caso de catalisadores estruturados com porosidade adequada para os processos catal?ticos. O uso de catalisadores combinados ao processo de pir?lise r?pida ? uma alternativa para a produ??o de compostos oxigenados de alto valor agregado, pois, al?m de elevar o rendimento e qualidade dos produtos, permite manipular a seletividade para um produto de interesse e, portanto, permite um maior controle sobre as caracter?sticas do produto final. Com base nesses argumentos, neste trabalho foram preparados catalisadores de tit?nio suportados em MCM-41 para uso em pir?lise catal?tica da biomassa, denominada de capim elefante. As rea??es de pir?lise da biomassa foram realizadas em um micro pirolisador, Py-5200, acoplado ao GC/MS, da empresa CDS Corporation, sediada nos Estados Unidos. Os catalisadores Ti-MCM-41, em diferentes raz?es molares, foram caracterizados por DRX, TG/DTG, FT-IR, MEV, FRX, UV-Vis?vel, adsor??o de nitrog?nio, distribui??o de di?metro de part?culas e medidas de ?rea espec?fica pelo m?todo BET. A partir dos testes catal?ticos foi poss?vel observar que os catalisadores sintetizados apresentaram bons resultados para a rea??o de pir?lise. Entre os catalisadores Ti-MCM-41 (raz?es molares Si/Ti = 25 e 50), o de raz?o Si/Ti=25 (temperatura de 400?C e 600?C) favoreceu o craqueamento de compostos oxigenados, tais como, ?cidos, alde?dos, cetonas, furanos e ?steres. J? a amostra de raz?o Si/Ti = 50 apresentou maior rendimento de arom?ticos oxigenados

Made available in DSpace on 2014-12-17T14:09:14Z (GMT). No. of bitstreams: 1 RenataMB_TESE.pdf: 1339744 bytes, checksum: 24902b1b3636b97bbd787863d62c1f99 (MD5) Previous issue date: 2012-08-09 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The fast pyrolysis of lignocellulosic biomass is a thermochemical conversion process for production energy which have been very atratactive due to energetic use of its products: gas (CO, CO2, H2, CH4, etc.), liquid (bio-oil) and charcoal. The bio-oil is the main product of fast pyrolysis, and its final composition and characteristics is intrinsically related to quality of biomass (ash disposal, moisture, content of cellulose, hemicellulose and lignin) and efficiency removal of oxygen compounds that cause undesirable features such as increased viscosity, instability, corrosiveness and low calorific value. The oxygenates are originated in the conventional process of biomass pyrolysis, where the use of solid catalysts allows minimization of these products by improving the bio-oil quality. The present study aims to evaluate the products of catalytic pyrolysis of elephant grass (Pennisetum purpureum Schum) using solid catalysts as tungsten oxides, supported or not in mesoporous materials like MCM-41, derived silica from rice husk ash, aimed to reduce oxygenates produced in pyrolysis. The biomasss treatment by washing with heated water (CEL) or washing with acid solution (CELix) and application of tungsten catalysts on vapors from the pyrolysis process was designed to improve the pyrolysis products quality. Conventional and catalytic pyrolysis of biomass was performed in a micro-pyrolyzer, Py-5200, coupled to GC/MS. The synthesized catalysts were characterized by X ray diffraction, infrared spectroscopy, X ray fluorescence, temperature programmed reduction and thermogravimetric analysis. Kinetic studies applying the Flynn and Wall model were performed in order to evaluate the apparent activation energy of holoceluloce thermal decomposition on samples elephant grass (CE, CEL and CELix). The results show the effectiveness of the treatment process, reducing the ash content, and were also observed decrease in the apparent activation energy of these samples. The catalytic pyrolysis process converted most of the oxygenate componds in aromatics such as benzene, toluene, ethylbenzene, etc / A pir?lise r?pida da biomassa lignocelul?sica ? um processo de convers?o termoqu?mica para produ??o de energia que vem se tornando muito atratativo devido ao aproveitamento energ?tico de seus produtos: g?s (CO, CO2, H2, CH4, etc), l?quido (bio-?leo) e carv?o vegetal. O bio-?leo ? o principal produto da pir?lise r?pida, sendo a sua composi??o e caracter?sticas finais intrinsecamente relacionadas ? qualidade da biomassa (elimina??o de cinzas, teor de umidade, teor de celulose, hemicelulose e lignina) bem como ? efici?ncia da remo??o dos compostos oxigenados que causam caracter?sticas indesej?veis como aumento da viscosidade, instabilidade, corrosividade e baixo poder calor?fico. Os compostos oxigenados s?o originados no processo de pir?lise convencional da biomassa onde o uso de catalisadores s?lidos, em geral, permite a minimiza??o destes produtos melhorando a qualidade do produto final, o bio-?leo. O presente trabalho teve como objetivo avaliar os produtos da pir?lise catal?tica do capim elefante (Pennisetum purpureum Schum) utilizando catalisadores s?lidos, ?xidos a base de tungst?nio, suportados ou n?o em materiais mesoporosos do tipo MCM-41, derivados da s?lica da casca do arroz, visando ? redu??o de compostos oxigenados produzidos na pir?lise. O tratamento da biomasssa atrav?s da lavagem com ?gua aquecida (CEL) ou lavagem com solu??o ?cida (CELix), bem como a aplica??o de catalisadores a base de tungst?nio nos vapores provenientes do processo de pir?lise, teve a finalidade de melhorar a qualidade dos produtos da pir?lise. A pir?lise convencional e catal?tica da biomassa foram realizadas em um micro pirolisador, Py-5200, acoplado ao GC/MS. Os catalisadores sintetizados foram caracterizados por Difra??o de raios X, Espectroscopia na regi?o do infravermelho, Fluoresc?ncia de Raios X, Redu??o por Temperatura Programada e An?lise termogravim?trica. Estudos cin?ticos aplicando o modelo de Flynn Wall foram realizados com a finalidade de avaliar a energia de ativa??o aparente da decomposi??o t?rmica da holoceluloce nas amostras de capim elefante (CE, CEL e CELix). Os resultados mostraram a efici?ncia do processo de tratamento, reduzindo o teor de cinzas, como tamb?m foi observada a diminui??o na energia de ativa??o aparente dessas amostras. O processo de pir?lise catal?tica converteu a maioria dos produtos oxigenados do CE em arom?ticos como benzeno, tolueno, etilbenzeno, etc