Estudo avançado para caracterização química de petróleo do Campo de Carmópolis-Sergipe

• Ano de defesa: 2013
• Autor(a) principal: Santos, Jandyson Machado
• Orientador(a): Wisniewski Junior, Alberto
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Programa de Pós-Graduação: Pós-Graduação em Química
• Palavras-chave em Português: Petróleo - Sergipe; Marcadores biológicos; Petróleo; Petróleo - Composição; Blendas de Óleo Bruto; Asfaltenos; Micropirólise off-line; Método SARA; Biomarcadores
• Palavras-chave em Inglês: Biochemical markers; Petroleum; Sergipe (Brazil); Blends Crude Oil; Asphaltenes; Micropyrolysis off-line; SARA; Biomarkers
• Área do conhecimento CNPq: CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA
• Link de acesso: https://ri.ufs.br/handle/riufs/6096

This work presents the use of analytical techniques, conventional and advanced for the chemical characterization of four samples of blends crude oils from the PETROBRAS station, Oiteirinhos II (Carmópolis-SE). These samples, which have different exploration characteristics, were identified as CEOL 1, CEOL 2, CEOL 3 and CEOL 4. After the collection in the field and subsequently separation of water residue through centrifugation at 2500 rpm, the blends were characterized by density, asphaltenes content, fractionation SARA (saturates, aromatics, resins and asphaltenes) and by the application of micropyrolisys off-line. The advanced characterization to elucidate the chemical relationship between the samples were made using the Thermogravimetry (TGA), Infrared Spectroscopy (IR), Spectroscopy in Ultraviolet (UV), Matrix Assisted Laser Desorption Ionization - Time of Flight - Mass Spectrometry (MALDI-TOF-MS), Gas Chromatography Mass Spectrometry (GC/MS), Gas Chromatography with Flame Ionization Detector (GC-FID) and Comprehensive Two-Dimensional Gas Chromatography (GC x GC). The blends CEOL 3 presented the highest density (0.9737 g mL-1), confirming the results of MALDI-TOF-MS, that shows predominantly high molecular mass compounds in the composition. The SARA fractionation indicates the Saturated fraction as the largest fraction in all oils (> 50%). The analysis of TGA explained similar bands of mass loss in all blends and their asphaltenes. The characterization by IR showed bands related to the hydrocarbon composition and the UV showed the presence of mono, di and tri aromatics structures in the blends as well in their respective asphaltenes. The chromatographic analysis (GC/MS, GC-FID and GC x GC) showed that all blends have a paraffinic profile, with the predominance of n-alkanes of low molecular weight (n-C10 to n-C40) and characteristics of oxide depositional environment (Pr/Ph>1) and lacustrine origin (CPI>1). The analysis by GC/MS showed that the distribution area relating to the free n-alkanes in the CEOL 3 blends is approximately 30% lower than the other samples, and that after the micropyrolysis process these areas become approximately the same. For biomarkers, GC/MS was possible to identify the majority presence of tri- and tetracyclic terpanes (m/z 191) and regular steranes (m/z 217) as the major constituents of the blends, pointing also to the release of occluded biomarkers in asphaltenic structures after the micropyrolysis process. The identification and subsequent correlation between biomarkers indicated that the blends crude oils studied have partial biodegradation characteristics, with a blend of mature and immature oils from terrigenous and/or algal organic matter.