Inhibition of asphaltene precipitation by hydrophobic CaO and SiO(2)nanoparticles during natural depletion and CO(2)tests

摘要

This paper addressed the effects of hydrophobic synthesized calcium oxide (CaO) and commercial silicon dioxide (SiO2) nanoparticles on the inhibition of asphaltene precipitation after asphaltene adsorption on the nanoparticles surface. CO2-oil interfacial tension (IFT) behaviours and batch experiment results were used for surveying asphaltene adsorption in the presence of nanoparticles, and natural depletion and CO(2)tests were done as a source of precipitation methods. The studied crude oil was located inunstable regions from the aspect view of asphaltene precipitation with a colloidal instability index (CII) of 1.392. The Langmuir isotherm modelled the asphaltene adsorption data well in the presence of both nanoparticles. Based on the results of CO2-oil interfacial tension, batch experiment and asphaltene precipitations during natural depletions and carbon dioxide tests, CaO not only adsorbed more asphaltene in compared to SiO(2)but also had the best application for precipitation inhibition. [Received: May 24, 2018; Accepted: October 24, 2018]