IQ - Instituto de Química
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Navegando IQ - Instituto de Química por Por Orientador "ANTONIOSI FILHO, Nelson Roberto"
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Item Produção e Caracterização de Biocombustíveis por Craqueamento de Óleo Vegetais via Catálise com Bauxita(Universidade Federal de Goiás, 2009-08-06) PRADO, Cinara Machado Rodrigues do; ANTONIOSI FILHO, Nelson Roberto; http://lattes.cnpq.br/5982964870999454In this work, raw bauxite, thermally activated calcined bauxite, calcined bauxite underwent acid treatment were the catalysts tested by its potential in the thermal catalytic cracking reaction looking forward to the production of biofuels from commercial soybean oil as an alternative to fossil fuels. The materials were characterized by the techniques ICP-OES, infrared spectroscopy, thermal analysis, X-ray diffraction and textural analysis. The chromatographic analysis of the biofuels obtained by cracking of commercial soybean oil showed hydrocarbon compounds such as alkanes, alkenes and aromatics, as well as some oxygenated compounds such as carboxylic acids, ketones and alcohols. The products generated by the thermal catalytic cracking process with thermally activated calcined bauxite showed better results than the thermal cracking products because of the low quantity of acids present, which provided biofuels with a lower acidity index, and absence of acrolein. Therefore, the catalyst which was used demonstrated activity in the secondary cracking process, in which fatty acids decompose and give rise to hydrocarbons. The cracking tests with raw bauxite generated a lower biofuels yield and significant amount of solid product and residual oil making unfeasible the process. In order to evaluated the potential of used industrial waste sources for production of alternative fuels, the cracking of the waste vegetable oil studied together with the optimum of the reaction conditions obtained satisfactory result in the gaseous and liquid yield and percentage of crude biofuels generated. The biofuel presented similar composition observed in the biofuels obtained in thermal catalytic cracking of xv commercial soybean oil. This proved that the thermal catalytic cracking process is an alternative solution for the reutilization of waste vegetable oil and fats, both, when discarded inadequately can become environment pollutantsItem 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.Item Determinação espectrofotométrica do teor de biodiesel metílico em misturas com óleo diesel(Universidade Federal de Goiás, 2009-11-25) SILVA, Marcos Alexandro Abreu e; ANTONIOSI FILHO, Nelson Roberto; http://lattes.cnpq.br/5982964870999454In this work it was developed a quantitative analytical methodology to determine the content of methyl biodiesel in diesel fuel through the fatty acid methyl ester reaction with the hydroxylamine hydrochloride in alkaline solutions, which they were acidified and converted to hydroxamic acids, followed by treatment with ferric ion to give the colored ferric hydroxamate complex, and afterwards extract in n-heptane and were analysed by UV-visible spectroscopy. It was made the optimization of the variables that interfere in the reaction, and parameters such as accuracy, precision and the limit of detection (LOD) among other parameters to assess the quality of the method developed it was also evaluated. The results indicated that the method has shown an excellent linearity in small intervals of biodiesel blend levels, an excellent determination coefficient of the calibration curve (R2 > 0.99) at a wide range of wavelength (420-440 nm). As well as it has also shown to be applied in a wide range of methyl biodiesel blend levels in diesel fuel (B1 to B20), and it is suitable to be used in the quality control procedures for the production of BX blends.