Made available in DSpace on 2014-12-17T14:08:49Z (GMT). No. of bitstreams: 1 AruzzaMMA_DISSERT.pdf: 1774693 bytes, checksum: a3fe2aad8bc5ee5d62f0d84e6a4733c6 (MD5) Previous issue date: 2011-07-01 / The use of biofuels remotes to the eighteenth century, when Rudolf Diesel made the first trials using peanut oil as fuel in a compression ignition engine. Based on these trials, there was the need for some chemical change to vegetable oil. Among these chemical transformations, we can mention the cracking and transesterification. This work aims at conducting a study using the thermocatalytic and thermal cracking of sunflower oil, using the Al-MCM-41 catalyst. The material type mesoporous Al-MCM-41 was synthesized and characterized by Hydrothermical methods of X-ray diffraction, scanning electron microscopy, nitrogen adsorption, absorption spectroscopy in the infrared and thermal gravimetric analysis (TG / DTG).The study was conducted on the thermogravimetric behavior of sunflower oil on the mesoporous catalyst cited. Activation energy, conversion, and oil degradation as a function of temperature were estimated based on the integral curves of thermogravimetric analysis and the kinetic method of Vyazovkin. The mesoporous material Al-MCM-41 showed one-dimensional hexagonal formation. The study of the kinetic behavior of sunflower oil with the catalyst showed a lower activation energy against the activation energy of pure sunflower oil. Two liquid fractions of sunflower oil were obtained, both in thermal and thermocatalytic pyrolisis. The first fraction obtained was called bio-oil and the second fraction obtained was called acid fraction. The acid fraction collected, in thermal and thermocatalytic pyrolisis, showed very high level of acidity, which is why it was called acid fraction. The first fraction was collected bio-called because it presented results in the range similar to petroleum diesel / O uso dos biocombust?veis remota ao s?culo XVIII, quando Rudolf Diesel realizou os primeiros ensaios utilizando o ?leo de amendoim como combust?vel em um motor de igni??o por compress?o. Com base nesses ensaios, constatou-se a necessidade de realizar algumas transforma??es qu?micas ao ?leo vegetal. Dentre essas transforma??es qu?micas, pode-se citar a transesterifica??o e o craqueamento. Este trabalho tem como objetivo, realizar um estudo utilizando-se o craqueamento t?rmico e termocatal?tico do ?leo de girassol, utilizando o Al-MCM-41 como catalisador. O material mesoporoso tipo Al-MCM-41 foi sintetizado hidrotermicamente e caracterizado pelos m?todos de difra??o de raios-X, microscopia eletr?nica de varredura, adsor??o de nitrog?nio, espectroscopia de absor??o na regi?o do infravermelho e an?lise termogravim?trica (TG/DTG). Ainda foi realizado o estudo do comportamento termogravim?trico do ?leo de girassol sobre o catalisador mesoporoso citado. Com base nas curvas integrais das an?lises termogravim?tricas e o m?todo cin?tico de Vyazovkin, foram estimados a energia de ativa??o, a convers?o e a degrada??o do ?leo em fun??o da temperatura. O material mesoporoso Al-MCM-41 apresentou forma??o hexagonal unidimensional. O estudo do comportamento cin?tico do ?leo de girassol com o catalisador mostrou uma menor energia de ativa??o frente ? energia de ativa??o do ?leo de girassol puro. Na pir?lise t?rmica e termocatal?tica do ?leo de girassol foram obtidas duas fra??es l?quidas. A primeira fra??o obtida foi denominada de bio?leo e a segunda fra??o obtida foi denominada de fra??o ?cida. A fra??o ?cida coletada tanto na pir?lise t?rmica como na termocatal?tica apresentou ?ndice de acidez muito elevado, raz?o pela qual foi denominada fra??o ?cida. A primeira fra??o coletada foi denominada de bio?leo porque apresentou resultados na faixa semelhante ao diesel de petr?leo

Made available in DSpace on 2014-12-17T15:42:27Z (GMT). No. of bitstreams: 1 KesiaKVC_TESE.pdf: 1888403 bytes, checksum: 628d99fa0e77dc19c5054fa5d201217e (MD5) Previous issue date: 2013-04-17 / In this work were synthesized and characterized the materials mesoporous SBA-15 and Al- SBA-15, Si / Al = 25, 50 and 75, discovered by researchers at the University of California- Santa Barbara, USA, with pore diameters ranging from 2 to 30 nm and wall thickness from 3.1 to 6.4 nm, making these promising materials in the field of catalysis, particularly for petroleum refining (catalytic cracking), as their mesopores facilitate access of the molecules constituting the oil to active sites, thereby increasing the production of hydrocarbons in the range of light and medium. To verify that the materials used as catalysts were successfully synthesized, they were characterized using techniques of X-ray diffraction (XRD), absorption spectroscopy in the infrared Fourier transform (FT-IR) and adsorption nitrogen (BET). Aiming to check the catalytic activity thereof, a sample of atmospheric residue oil (ATR) from the pole Guamar?-RN was performed the process by means of thermogravimetry and thermal degradation of catalytic residue. Upon the curves, it was observed a reduction in the onset temperature of the decomposition process of catalytic ATR. For the kinetic model proposed by Flynn-Wall yielded some parameters to determine the apparent activation energy of decomposition, being shown the efficiency of mesoporous materials, since there was a decrease in the activation energy for the reactions using catalysts. The ATR was also subjected to pyrolysis process using a pyrolyzer with gas chromatography coupled to a mass spectrometer. Through the chromatograms obtained, there was an increase in the yield of the compounds in the range of gasoline and diesel from the catalytic pyrolysis, with emphasis on Al-SBA-15 (Si / Al = 25), which showed a percentage higher than the other catalysts. These results are due to the fact that the synthesized materials exhibit specific properties for application in the process of pyrolysis of complex molecules and high molecular weight as constituents of the ATR / No presente trabalho foram sintetizados e caracterizados os materiais mesoporosos SBA-15 e Al-SBA-15, Si/Al= 25, 50 e 75, descobertos por pesquisadores da Universidade da Calif?rnia- Santa B?rbara- EUA, tendo di?metro de poros variando entre 2 a 30 nm e espessura das paredes de 3,1 - 6,4 nm, tornando estes materiais promissores na ?rea da cat?lise, especificamente para o refino do petr?leo (craqueamento catal?tico), j? que seus mesoporos facilitam o acesso das mol?culas constituintes do petr?leo aos s?tios ativos, aumentando assim a produ??o de produtos na faixa dos hidrocarbonetos leves e m?dios. Para verificar se os materiais utilizados como catalisadores haviam sido sintetizados com sucesso, os mesmos foram caracterizados atrav?s das t?cnicas de difra??o de raios-X (DRX), espectroscopia de absor??o na regi?o do infravermelho com transformada de Fourier (FTIR) e adsor??o de nitrog?nio (BET). Com o intuito de verificar a atividade catal?tica dos mesmos, utilizou-se uma amostra de Res?duo Atmosf?rico de petr?leo (RAT), proveniente do P?lo de Guamar?- RN, realizando-se atrav?s da termogravimetria o processo de degrada??o t?rmica e catal?tica do res?duo. Mediante as curvas obtidas, observou-se uma redu??o na temperatura de in?cio do processo de decomposi??o catal?tica do RAT. Pelo modelo cin?tico proposto por Flynn- Wall obtiveram-se alguns par?metros para determina??o da energia de ativa??o aparente das decomposi??es, ficando evidenciada a efici?ncia dos materiais mesoporosos, j? que houve uma diminui??o da energia de ativa??o para as rea??es utilizando os catalisadores. O RAT tamb?m foi submetido ao processo de pir?lise utilizando-se um pirolisador com cromatografia gasosa, acoplado a um espectr?metro de massa. Mediante os cromatogramas obtidos, observou-se um aumento no rendimento dos compostos na faixa da gasolina e diesel oriundos da pir?lise catal?tica, com ?nfase para o Al-SBA-15 (Si/Al= 25), que apresentou um percentual superior aos demais catalisadores. Esses resultados se devem ao fato dos materiais sintetizados exibirem propriedades espec?ficas, para aplica??o no processo de pir?lise de mol?culas complexas e com alto peso molecular, como os constituintes do RAT