Avaliação dos teores de enxofre em amostras de gasolina nas redes de distribuição de combustíveis na cidade de Natal/RN

• Autor(a) principal: Costa, Letícia Gracyelle Alexandre
• Data de Publicação: 2015
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/handle/123456789/38295
• topic: Gasolina; Fluorescência na região do Ultravioleta; Enxofre; Gasoline; Sulphur; Fluorescence in the ultraviolet region; Química do Petróleo

The sulfur content in petroleum products is an important variable, since sulfur compounds are associated with problems from storage to distribution. Currently, sulfur levels in fuels have been reduced by government agencies to reduce air pollution. According to ANP Resolution No. 40/2013 the sulfur content must be a maximum of 50 mg/kg. For these and other reasons, one of the means to quantify the sulfur with a high value of course, is by validated methods. The validation of the methodology for fluorescence sulfur determination in the UV region was carried out taking as base to ASTM D5453 for determining the sulfur content in gasoline samples of the ordinary and additive type, distributed at gas stations in the city of Natal, RN. It was used certified reference material for the validation and construction of the curve for reading the collected samples. The method showed a validated after 0.006079 mg/L detection limit, a limit of quantitation of 0.020265 mg/L and a coefficient of determination r2 0.9994 curve. The standard addition recovery tests showing 91.0% were made. The tests showed that the method is selective and reliable but must be used the operating conditions under which the experiments were conducted because the sensitivity parameters, injection and quality of the solvent volume showed significant effects, and the detector sensitivity the most critical factor. The results showed that all samples are in accordance to the sulfur content and other analyzed parameters. It is still observed a tendency of leaded gasoline have higher sulfur content than regular gasoline due to the presence of derivatives of sulfonic acids additives. Thus, it can be concluded that the UV fluorescence technique can be applied to gas samples as well as assist in monitoring the concentrations of sulfur contained in gasoline sold in Natal.