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Item Síntese e caracterização de peneira molecular mesoporosa mcm-41 com níquel impregnadas e in situ(Universidade Federal de Goiás, 2008-05-14) KLEIN, Karina Vitti; NUNES, Liliane Magalhães; http://lattes.cnpq.br/6591210839894513The new family mesoporosas molecular sieves, known as M41S, have been very studied since its discovery in 1992, with bigger prominence for MCM-41, that had its mesoporosa structure that allows ample applications in catalytic processes. In this work were studied two reactions conditions of preparation of the MCM-41 and three forms of nickel incorporation. In the synthesis of the MCM-41 the hidrotérmico treatment and in conditions was used surrounding, while in the incorporation, was used to impregnation of ions nickel and nanopartículas of nickel oxide, as well as the direct synthesis where the nickel was introduced in the structure of the MCM-41, during the synthesis. The gotten materials had been characterized by elementary nickel analysis, X-ray diffraction, nitrogen adsorption/desorption, FT-IR spectra, thermogravimetric analysis, thermoprogrammed reduction. The characterizations had indicated that it had the formation of the mesoporosa structure with periodic pore system, typical of the MCM-41, in both methods of synthesis, being able to be evidenced the biggest viability of the synthesis of the MCM-41 in the surrounding conditions. It can also be verified that it had nickel incorporation in all samples, independent of as this element was inserted. The introduced samples that had had nickel during the synthesis had presented greater excessively average diameter of pores in relation. After the characterization, the samples with nickel had been tested as in the reaction of conversion of carbon monoxide the high temperatures catalytic, known as HTS reaction, presenting activity.Item Avaliação e desenvolvimento de métodos de caracterização e controle de qualidade de biodieseis metílicos e etílicos por cromatografia gasosa capilar a altas temperaturas(Universidade Federal de Goiás, 2008-09-01) REZENDE, Daniela Rodrigues de; ANTONIOSI FILHO, Nelson Roberto; http://lattes.cnpq.br/5982964870999454In this work, a chromatographic method for simultaneous determination of free and total glycerol, mono-, di- and triacylglycerides contents in biodiesel it was evaluated. It s an alternative method for the reference ASTM D-6584 and EN 14105 standard methods with the advantages of being more practical, economical and faster. Moreover the method is applicable to methylic and ethylic biodiesel and biodiesel with long chain triacylglycerides. For this, High Temperature Capillary Gas Chromatography (HT-CGC) on short (15 m) and non-polar column (DB-5HT) and flame ionization detection were used. The accuracy of EN 14103 standard method in the determination of ester content in biodiesel also it was evaluated. Furthermore, a rapid chromatographic method for accompanying the conversion of fats and oils in biodiesel in function of alterations in the reactive conditions of the production system it is presented. For this, the same column and detector were used. The monitoring can be done in just 13 minutes of analysis and it was realized through of the relative proportion between methyl or ethyl esters and triacylglycerides total areas. In addition, the influence of silylation in the analysis of acylglycerides by gas chromatography was also investigated. Mono and diacylglycerides reference standards, silylated and non-silylated, were analyzed by HT-CGC. In non-silylated standards intramolecular reactions occurring inside the chromatographic column it was observed. It was verified that the intensity of these reactions depends on the type and unsaturation degree of the acylglycerides, of the carbon chain length, injection mode, injector temperature and column conditions. Therefore, silylation protects the hydroxyl groups for this kind of reaction and it is a necessary step in gas chromatographic analysis of mono- and diacylglycerides.Item Aproveitamento de rejeitos da indústria de atomatados para a produção e caracterização de extratos ricos em licopeno, β-Caroteno e Vitamina E(Universidade Federal de Goiás, 2006-03-17) SILVA, Fernanda Dias; ANTONIOSI FILHO, Nelson Roberto; http://lattes.cnpq.br/5982964870999454The production of industrial foods derived from tomato generates high levels of rejects that are composed basically of seeds and tomato peels. This reject it is rich in carotenoids, especially lycopene and β-carotene, which are pigments whose ingestion is directly linked to the decrease of the risk of chronic-degenerative diseases. The present study has as objective develops simplified and efficient extraction and analysis methods of lycopene and β-carotene starting from this reject using palm oil as coadjutant, seeking the subsequent use of this extract for enrichment of products of easy access to classes economically inferior of the population and as a vehicle of medicines. Initially it was developed the chromatographic analysis method for three columns of RP-HPLC: C18 Chromolith SpeedROD (50 mm x 4,6 mm), C18 Nova-Pack (300 mm x 3,9 mm x 4 µm) and C30 YMC Carotenoid (250 mm x 4,6 mm x 5 µm). All the columns present a considerable reduction in the time of analysis and efficient separation between lycopene and β-carotene, when compared to the analysis reported on scientific literature. Later it was done a study of the thermal stability of the pigments by means of TG, DSC and RP-HPLC seeking to evaluate the maximum temperature which the reject can be heated without the occurrence of considerable losses of the pigments. The thermogravimetric curves demonstrated that the loss of mass happens to temperatures higher than those observed by the degradations of the pigments by RP-HPLC. It means that occurs the transformation of lycopene and β-carotene in intermediary compounds which are volatilized in higher temperatures. For the development of the extraction method several variables were tested being obtained the following optimized condition: 25 g of sample was dissolved in 50 mL of hexane and 0.1 mL of palm oil, shaking by 90 minutes under 50ºC. The proposed method demonstrated to be viable once it happens in only one stage, with the use of only an solvent which can be used again after the process. The time of extraction is completely acceptable, as well as the amount of solvent used, being all the parameters compatible with industrial implementation. The oily extract was still characterized with regard to the tocopherols and tocotrienols levels in the palm oil as well as the fatty acid and triacylglicerol compositions. It was obtained the prevalence of y-tocotrienol, oleic and palmitic acids and POO and POP triacylglicerides.