SiO2 Biogenic Nanoparticles and Asphaltenes: Interactions and Their Consequences Investigated by QCR and GPC-ICP-HR-MS

The processes in which crude oil asphaltene aggregates are adsorbed onto surfaces have been the subject of debate in recent years. Different thermodynamic, theoretical, and empirical models have been proposed to explain the interaction of asphaltenes with these surfaces and have found different behaviors. In this work, asphaltene adsorption onto SiO2 biogenic nanoparticles was experimentally monitored by studying it through two analytical techniques, namely, gel permeation chromatography coupled with inductively coupled plasma and high-resolution mass spectrometry (GPC-ICP-HR-MS) to follow the changes in aggregate size distributions in solutions and a quartz crystal resonator (QCR) sensor to detect and follow the destabilization with n-heptane, thus allowing the correlation of the different stabilities and deposition tendencies with the changes in aggregate size distributions. The results show that the nanoparticles interact in a preferential way with the larger asphaltene aggregates, and, once these large aggregates are adsorbed, there is no tendency for new large aggregate formation. Thus, a reduction in the deposition is observed. This indicates that, in this range of concentration, there is no equilibrium for aggregate formation and that these larger aggregates can be effectively removed. This finding opens new methodologies for study regarding asphaltene removal.

Automated summary

The study shows that SiO2 biogenic nanoparticles interact selectively with previously adsorbed larger asphaltene aggregates, and there is no trend for new large aggregate formation. This finding offers new methodologies for asphaltene removal.