Direct Assessment of Inhibitor and Solvent Effects on the Deposition Mechanism of Asphaltenes in a Brazilian Crude Oil

Autor(es)

da Silveira Balestrin, Lia Beraldo ^[1] ; Francisco, Renata Dias ^[1] ; Bertran, Celso Aparecido ^[1] ; Cardoso, Mateus Borba ^{[2, 3]} ; Loh, Watson ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Chem, BR-13084970 Campinas, SP - Brazil

^[2] Natl Ctr Res Energy & Mat CNPEM, Brazilian Nanotechnol Lab LNNano, BR-13083970 Campinas, SP - Brazil

^[3] Natl Ctr Res Energy & Mat CNPEM, Brazilian Synchrotron Light Lab LNLS, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ENERGY & FUELS; v. 33, n. 6, p. 4748-4757, JUN 2019.
• Citações Web of Science: 1

Resumo

The study of the asphaltene deposition mechanism is critical to understand and solve important problems in the petroleum industry. The same is valid for the selection of inhibitors to control or prevent asphaltene flocculation and/or deposition. However, most of the current information on these processes is obtained by experiments performed using model solvent systems. In the present study, we used quartz crystal microbalance (QCM) measurements as well as laser scanning confocal microscopy to characterize the asphaltene deposition directly measured in a Brazilian crude oil at different conditions of flocculant concentration and using inhibitors with different chemical features. Measurements under accelerated sedimentation (LUMiSizer) were also employed to evaluate inhibitor capacity in crude oil systems, in this case using a large excess of n-heptane. Overall, QCM results suggest that the diffusion-limited aggregation (DLA) model can be used to describe systems close to or above the concentration of the onset of asphaltene precipitation. The transition to a behavior that follows the reaction-limited aggregation (RLA) model occurs when an inhibitor added or the flocculant concentration is reduced farther from the onset. Moreover, accelerated sedimentation shows that the inhibitors tested act by preventing aggregate growth. Therefore, these results highlight the importance of performing time-dependent experiments directly in crude oils and support the use of these methodologies to optimize inhibitor selection for different crude oils. (AU)

• Processo FAPESP: 15/25406-5 - Organizando a matéria: colóides formados por associação de surfactantes, polímeros e nanopartículas
• Beneficiário: Watson Loh
• Modalidade de apoio: Auxílio à Pesquisa - Temático