Mestrado em Química

URI Permanente para esta coleção

http://repositorio.ufes.br/handle/10/17502

Nível: Mestrado Acadêmico
Ano de início: 2006
Conceito atual na CAPES: 5
Ato normativo: Homologação da 85ª Reunião do CTC-ES, Parecer CNE/CES nº 163/2005.
Processo nº 23001.000081/2005-56 do Ministério da Educação.
Publicado no DOU 28/07/2005, seção 1, página 11)
Periodicidade de seleção: Anual
Área(s) de concentração: Química
Url do curso: https://quimica.vitoria.ufes.br/pt-br/pos-graduacao/PPGQ/detalhes-do-curso?id=954

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Navegando Mestrado em Química por Autor "Aquije, Glória Maria de Farias Viégas"

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    Estudo da corrosão naftênica por espectrometria de massas de altíssima resolução e exatidão (ESI –FT-ICR MS) & microscopia de força atômica
    (Universidade Federal do Espírito Santo, 2014-01-01) Dias, Heloisa Pinto; Romão, Wanderson; Aquije, Glória Maria de Farias Viégas; Freitas, Marcos Benedito José Geraldo de; Vaz, Boniek Gontijo
    Naphthenic acids are considered primarily responsible for corrosion in the oil refining process, and if not properly monitored, the naphthenic corrosion can cause severe damage to the petrochemical industry. In the first chapter of this work, two oil samples treated at 300°C/2h 350°C/6h, were brought in contact with carbon steel AISI 1020 for 15 days. The acidity of the original and products from oil heat treatment was monitored by TAN ESI (-) - FT-ICR-MS and corrosion on steel was monitored by AFM. The ESI (-) - FT-ICR MS showed that the O2 class, the major species detected were majority carbon number of C25-C32 and DBE = 3. For treatment at 350°C/6h, there was a reduction of ~ 80% in the TAN. The results showed that AFM topography of the steel surface exposed to the oil treated at 300°C/2h has higher effects of corrosion, since the pattern of roughness measured by "peak to peak height" of the surface, indicated that the surface exposed to the oil 300°C/ 2h, although it presents a number of irregularities is less pronounced, the surface exposed to the oil-treated steel at 350°C/6h. In the second chapter, two oils with different J and G acidity were characterized by ESI (-) - FT-ICR MS. The AISI 316 steel was analyzed by optical microscopy, atomic force microscopy and Raman spectroscopy. The results showed that the major classes were identified in the samples classes O2 and N2. Regarding O2 class, the major species detected were majority of carbon number C24 and C35 = 3 DBE and DBE and C29-C35 = 4. The AFM images showed that the interval for 14 days, the steel exposed to oil J, showed strong topographic changes from white, characterizing the onset of the corrosion process. This information is consistent with the Raman spectra that for this period of time the formation of goethite, hematite and magnetite were evidenced. Topographical changes to the exposed steel to oil G could only be observed after 21 days of analysis by AFM. The third chapter, a sample oil was thermally treated in the presence and absence of catalyst at 300 and 350 ° C for a period of 2, 4 and 6 hours. The acidity of the original oil and products derived from thermally treated catalyst was determined by TAN. The variation in the content of polar samples, particularly class O2 was monitored by ESI (-) - FT-ICR MS. Generally, the major classes identified for both samples were N, NO2, and O2, respectively. Regarding O2 class corresponding to naphthenic acids, the major species were majority of C25-C32 and DBE = 3. There was a 43.50% reduction in the degraded oil at 350°C for 4h in the presence of the catalyst thus demonstrating the efficiency of removal of naphthenic acids under the conditions evaluated.
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    Síntese de novo composto imínico com atividade antioxidante e anticorrosiva aplicado em biodiesel de soja
    (Universidade Federal do Espírito Santo, 2019-05-14) Martins, Lucas Ferreira; Silveira, Vivian Chagas da; Lacerda Junior, Valdemar; Romão, Wanderson; Aquije, Glória Maria de Farias Viégas; Santos, Reginaldo Bezerra dos
    Biodiesel is a renewable biofuel produced from transesterification of vegetable oils and animal fats with short-chain alcohols. Despite being environmentally friendly, biodiesel has low oxidative stability and is gradually degraded by autooxidation reactions. Furthmore, metallic structures are corroded whenimmersed in biodiesel, for being a higher electric conductive (compared with petro diesel) and hygroscopic medium. To rise oxidative stability and not damage fuel engines and storage tanks, antioxidants (reduce catalytic radical reactions) and corrosion inhibitors (adsorbs on metallic surface) are added in biodiesel. In this dissertation are discussed the synthesis of the new phenolic-iminic compound N,N’-bis-(4-hexadecanoate)salicylidene-ethylenedimaine,named IM, to play as multifunctional molecule, exhibiting antioxidative and corrosion inhibition activity. IM reduced carbon steel AISI 1020 coupons immersed in biodiesel, at room temperature and under heating and showed better results than commercial compounds butylated hydroxytoluene (BHT), tert-butylhydroquinone (TBHQ) and pyrogallol (PY). IM also increased oxidative stability of biodiesel contaminated with cooper ions, working as metal chelator, and reduced dissolved oxygen in biodiesel, working as oxygen scavenger. Corrosion was evaluated by light microscopy, scanning electron microscopy and atomic force microscopy. Oxidative stability tests were made by PetroOXY method