Estudo do efeito da distância de migração secundária do óleo na composição de compostos nitrogenados por FT-ICR MS

• Autor(a) principal: Brito, Talita Pinheiro de
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/11726
• topic: Espectrometria de massas; FT-ICR MS; Óleo cru; Petroleômica; Migração secundária do petróleo; Compostos nitrogenados; Mass spectrometry; Crude oil; Petroleomics; Secondary oil migration; Nitrogenous compounds; CIENCIAS EXATAS E DA TERRA::QUIMICA::FISICO-QUIMICA

Crude oil is a complex mixture containing a variety of organic species, with hydrocarbons constituting the most abundant fraction of this matrix, and a small number of polar constituents and some metals. Among the polar constituents, nitrogenous compounds have been widely used in geochemical studies. The distance traveled by the crude oil from the source kitchen to the reservoir is an important parameter in the search for new oil accumulations. For this type of information, reliable and robust molecular markers are desirable to estimate the distance migrated by crude oil. In the present work, Fourier transform ion cyclotron resonance mass spectrometry coupled to the electrospray in negative mode was used in the chemical characterization of nitrogenous compounds in 14 oil samples from three different Brazilian fields (C, H and G). Heteroatomic compounds classes detected in the samples were N, N2, NO, NO2, NS, O, and O2. It was found that the average molecular mass (AMM) for each DBE value of nitrogen compounds (N) can be used as an indicator of oil migration distance within a Brazilian basin. Moreover, a correlation of relative abundance of three carbon atom ranges of alkyl-carbazoles (C12-C20, C21-C29, C30+) and benzocarbazoles (C16-C20, C21-C29, C30+) revealed enrichment or depletion of these species based on their degree of alkylation which can be associated to the polarity of these species and consequently to their chemical fractionation along the petroleum migration. Finally, ratios (C31+/C30-) calculated between of relative abundance of carbazoles and benzocarbazoles divided by two groups of carbon atom numbers show a potential to estimate oil migration distance as their values become higher in petroleum samples collected furthest from the source kitchen. The results obtained indicating the potentiality of using it as new parameters to access secondary migration crude oil distance.