?rea de concentra??o: Qu?mica org?nica. / Data de aprova??o retirada da vers?o impressa do trabalho. / Palavras-chave ausentes no Resumo/Abstract. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-08-04T17:58:56Z No. of bitstreams: 2 myrlene_oliveira_ottone.pdf: 35150534 bytes, checksum: f6a5ce4d99508eed910f62e1d6984580 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-08-14T13:58:08Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) myrlene_oliveira_ottone.pdf: 35150534 bytes, checksum: f6a5ce4d99508eed910f62e1d6984580 (MD5) / Made available in DSpace on 2017-08-14T13:58:08Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) myrlene_oliveira_ottone.pdf: 35150534 bytes, checksum: f6a5ce4d99508eed910f62e1d6984580 (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O SiO2-SO3H ? um catalisador heterog?neo, sintetizado a partir de areia de constru??o e carbonato de s?dio, o qual, vem se mostrando eficaz nas s?nteses org?nicas. No presente trabalho, esse catalisador foi usado na s?ntese de ?steres benz?licos e fen?licos, realizada em apenas uma ?nica etapa, com rendimentos entre 80 e 95%. E devido a esse alto rendimento, foi tamb?m realizado rea??es de cetaliza??es, utilizando glicerol, 2,2-dimetil-1,3-propandiol e 1,1,1-hidroximetil-propanol e diversas cetonas. As rea??es com o glicerol apresentaram rendimentos baixos, por ser uma esp?cie muito polar e interagir com os poros da s?lica, evitando a colis?o com as mol?culas de cetonas. Diante desses resultados, foi poss?vel produzir um catalisador heterog?neo que al?m de diminuir o impacto ambiental, carrega caracter?sticas ben?ficas e eficientes para s?ntese org?nica, poss?vel se tonar eficaz para futuras rotas sint?ticas. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The SiO2 - SO3H is a heterogeneous catalyst synthesized from building sand and sodium carbonate. It has proven to be effective for organic syntheses. In study the catalyst was used in the synthesis of benzyl esters and phenolics and the yields between 80 and 95%. And the high yield was also performed cetaliza??es reactions using glycerol, 2,2- dimethyl- 1,3- propandiol and 1,1,1 -hydroxymethyl- propanol and various ketones. The reactions with glycerol had low yield justified very polar species and interact with the pores of silica, avoiding collision with ketone molecules. These results it was possible to produce a heterogeneous catalyst in addition to reducing environmental impact, carries beneficial and efficient features for organic synthesis. It can be effective tonar for future synthetic routes.

Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-11-05T21:41:01Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) adeline_cristina_pereira.pdf: 1853338 bytes, checksum: 3a89c6c8bdef22cb94ac757e146a9e2a (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-11-10T11:58:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) adeline_cristina_pereira.pdf: 1853338 bytes, checksum: 3a89c6c8bdef22cb94ac757e146a9e2a (MD5) / Made available in DSpace on 2018-11-10T11:58:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) adeline_cristina_pereira.pdf: 1853338 bytes, checksum: 3a89c6c8bdef22cb94ac757e146a9e2a (MD5) Previous issue date: 2018 / O catalisador denominado SiO2-SO3H foi empregado em tr?s processos reacionais distintos: transesterifica??o, cetaliza??o e eterifica??o. Utilizado em uma propor??o de 20% (m/m) contendo tolueno, o SiO2-SO3H se mostrou muito eficiente no processo de transesterifica??o de triacilglicer?deos fornecendo glicerol e ?steres met?licos de ?cidos graxos (biodiesel) com um rendimento de 98%. Empregou-se o glicerol obtido como reagente em uma mistura com acetona, em um meio reacional livre de solventes e utilizando o SiO2-SO3H, obteve-se convers?o total e 100% de seletividade para o composto contendo o anel de 5 membros [(?)- 2,2-Dimetil-4-hidroximetil-1,3-dioxolano] conhecido como solketal, um produto qu?mico vers?til, com diversas aplica??es, na ind?stria de cosm?tico e farmac?utica, al?m de aditivo para diesel com a finalidade de reduzir o ponto de congelamento, melhorar as propriedades lubrificantes e aumentar a pot?ncia anti-detonante. Posteriormente realizou-se o processo de eterifica??o do solketal, empregando o catalisador SiO2-SO3H, levando a forma??o do 4,4'-[oxibis(metileno)]-bis(2,2-dimetil-1,3-dioxolano)], ??ter de di-solketal?, precursor do diglicerol, importante emulsificante das ind?strias farmac?utica e aliment?cia com 98% de rendimento. A eterifica??o do solketal foi tamb?m promovida empregando o catalisador denominado SiO2-Nb levando a forma??o do 4,4'-[oxibis(metileno)]-bis(2,2-dimetil-1,3-dioxolano)], ??ter de di-solketal? com um rendimento de 96%. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018. / The catalyst called SiO2-SO3H was at the forefront of several distinct reaction processes: transesterification, ketalization and etherification. Used at a ratio of 20% (m / m) to toluene, SiO2 -SO3H became very efficient in the transesterification process of triacylglycerides, providing glycerol and fatty acid methyl esters (biodiesel) in 98% yield. The glycerol was used as reagent in a mixture with acetone, in a solvent-free reaction medium and in the use of SiO2 -SO3H, obtained and 100% total resolution for the compound with the 5-membered compound [(?) - 2,2-Dimethyl-4-hydroxymethyl-1,3-dioxolane], known as solalto, a versatile chemical with various applications in the cosmetic and pharmaceutical industry, as well as a diesel additive for freezing purpose, lubricants and increase anti-detonating power. Subsequently, the sputtering determination was carried out using the SiO2 -SO3H catalyst, leading to the formation of 4,4 '- [oxybis (methylene)] bis (2,2-dimethyl-1,3-dioxolane)], di-solketal, precursor of diglycerol, a major emulsifier of the pharmaceutical and food industries in 98% yield. The etherification of the solketal was also promoted using the catalyst called SiO2-Nb leading to the formation of 4,4 '- [oxybis (methylene)] bis (2,2-dimethyl-1,3-dioxolane)], di -solketal "in 96% yield.

Made available in DSpace on 2014-12-17T14:08:46Z (GMT). No. of bitstreams: 1 LarissaCLA_DISSERT.pdf: 2411784 bytes, checksum: bc6175bf8ed881abf12e8c0d17d59264 (MD5) Previous issue date: 2011-07-04 / Biodiesel is an alternative fuel, renewable, biodegradable and nontoxic. The transesterification of vegetable oils or animal fat with alcohol is most common form of production of this fuel. The procedure for production of biodiesel occurs most commonly through the transesterification reaction in which catalysts are used to accelerate and increase their income and may be basic, acid or enzyme. The use of homogeneous catalysis requires specific conditions and purification steps of the reaction products (alkyl ester and glycerol) and removal of the catalyst at the end of the reaction. As an alternative to improve the yield of the transesterification reaction, minimize the cost of production is that many studies are being conducted with the application of heterogeneous catalysis. The use of nano-structured materials as catalysts in the production of biodiesel is a biofuel alternative for a similar to mineral diesel. Although slower, can esterify transesterified triglycerides and free fatty acids and suffer little influence of water, which may be present in the raw material. This study aimed at the synthesis, characterization and application of nano-structured materials as catalysts in the transesterification reaction of soybean oil to produce biodiesel by ethylic route. The type material containing SBA-15 mesoporous lanthanum embedded within rightly Si / La = 50 was used catalyst. Solid samples were characterized by X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, nitrogen adsorption and desorption. For the transesterification process, we used a molar ratio of 20:1 alcohol and oil with 0.250 g of catalyst at 60?C and times of 6 hours of reaction. It was determined the content of ethyl esters by H-NMR analysis and gas chromatography. It was found that the variable of conversion obtained was 80%, showing a good catalytic activity LaSBA-15 in the transesterification of vegetable oils via ethylic route / O biodiesel ? um combust?vel alternativo, renov?vel, biodegrad?vel e n?o t?xico. A transesterifica??o dos ?leos vegetais ou gordura animal com ?lcool ? a forma mais usual de produ??o desse combust?vel. O procedimento de produ??o de biodiesel ocorre mais comumente atrav?s da rea??o de transesterifica??o, na qual se utiliza catalisadores para acelerar e aumentar seu rendimento, podendo ser b?sico, ?cido ou enzim?tico. O uso da cat?lise homog?nea requer condi??es e etapas espec?ficas de purifica??o dos produtos da rea??o (?ster alqu?licos e glicerol) e remo??o do catalisador ao t?rmino da rea??o. Como alternativa para melhorar o rendimento da rea??o de transesterifica??o, minimizar os custos com a produ??o ? que muitos estudos est?o sendo realizados com aplica??o de cat?lise heterog?nea. O uso de materiais nano-estruturados como catalisadores na produ??o de biodiesel ? uma alternativa para obter um biocombust?vel semelhante ao diesel mineral. Mesmo sendo mais lentos, conseguem transesterificar os triglicer?deos e esterificar os ?cidos graxos livres, al?m de sofrerem pouca influ?ncia da ?gua, que possa estar presente na mat?riaprima. Este trabalho teve como objetivo a s?ntese, caracteriza??o e aplica??o de materiais nano-estruturados como catalisadores na rea??o de transesterifica??o de ?leo de soja, para obten??o de biodiesel pela rota et?lica. O material do tipo SBA-15 contendo lant?nio incorporado na estrutura mesoporosa, com raz?o Si/La=50, foi utilizado como catalisador. As amostras s?lidas foram caracterizadas por difra??o de raios-X, an?lise termogravim?trica, espectroscopia na regi?o do infravermelho, adsor??o e dessor??o de nitrog?nio. Para o processo de transesterifica??o, utilizou-se uma raz?o molar entre ?lcool e ?leo de 20:1 com 0,250 g de catalisador, temperatura de 60?C e tempos de 6 horas de rea??o. Determinou-se o teor de ?steres et?licos pela an?lise de H-RMN e cromatografia a g?s. Foi verificado que a vari?vel de convers?o obtida foi de 80%, mostrando uma boa atividade catal?tica do LaSBA- 15 na transesterifica??o do ?leo de soja via rota et?lica