Monitoração da contaminação de diesel usando a espectrofluorimetria

• Ano de defesa: 2012
• Autor(a) principal: Tomazzoni, Giancarlo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Tecnológica Federal do Paraná; Curitiba; Programa de Pós-Graduação em Ciência e Tecnologia Ambiental
• Palavras-chave em Português: Biodiesel; Diesel - Contaminação; Fluorescência; Espectrofotometria; Análise de componentes principais; Óleos vegetais como combustível; Tecnologia ambiental; Biodiesel fuels; Diesel fuels - Contamination; Fluorescence; Spectrophotometry; Principal components analysis; Vegetable oils as fuel; Green technology
• Link de acesso: http://repositorio.utfpr.edu.br/jspui/handle/1/894

The use of adulterated fuels causes damage in vehicles, wear parts, increase in fuel consumption, as well as emission of particulate material and exhaust gas. The methods used for determination of diesel adulteration, in general, are not fast, they include various stages of sample preparation, at high cost and require complex equipment that needs constant calibration and measurement, besides involving time consuming to collect and logistics of samples. In order to evaluate possible adulteration of diesel with fresh vegetable oil or waste, rather than biodiesel, spectrofluorimetry was used as analytical technique for this purpose. Initially, Individual mixtures of diesel (S1800) were prepared containing 2, 4, 6, 8, 10, 15 and 20 % of oil and soybean biodiesel, canola and residual frying oil. These fuels were analyzed by Infrared and spectrofluorimetry, using spectrofluorimeter from brands Varian and Quimis (prototype), which use LEDs as excitation light source instead of the xenon lamp. Only with the spectra resulting from this analysis any distinction was obtained among the desired samples, making necessary the usage of the principal component analysis (PCA). Based on the PCA carried out from the results obtained in the prototype, it was clearly distinguished diesel from biodiesel or vegetable oil, as well as, separated mixtures of diesel/oil and diesel/biodiesel of soybean and frying. The results obtained from Varian showed clear distinction for mixtures containing oil and biodiesel frying only. The infrared results showed remarkable difference between mixtures of diesel/oil and diesel/biodiesel for all the samples in the region 1700-1800 cm-¹. However, this technique was not effective in distinguishing biodiesel and/or vegetable oil added to diesel, without application of the PCA. Moreover, for the purpose of putting evidence in specific fluorescence signals in fuels, for example, the presence of chlorophyll signals in vegetable oils and / or monoesters,some substances (additives) were used, such as Phoroglucine, Fluorescein, Stains All, p-anisaldehyde, Dimethylaminobenzaldehyde, Sudan III, Nile Red and Rhodamine B. Which were added to samples of pure diesel, vegetable oil and biodiesel. The samples were analyzed in Varian spectrofluorimeter, where it was found that the Sudan III was the only one to show effective results under the conditions tested. Using this compound, the fluorescence of chlorophyll present in oils and monoesters is highlighted (675 nm), including the frying oil and biodiesel. These results allowed discrimination of diesel, vegetable oil and biodiesel, as well as the rapid characterization of fresh vegetable oil addition or residual to diesel.