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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

S?ntese de biodiesel, glicerol, solketal e ?ter de solketal

Pereira, Adeline Cristina 12 April 2018 (has links)
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.

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