Influence of Fatty-Alkylamine Amphiphile on the Asphaltene Adsorption/Deposition at the Solid/Liquid Interface under Precipitating Conditions

Abstract

The ability of a fatty-alkylamine amphiphile to inhibit asphaltene adsorption/deposition, as well as its ability to disperse the asphaltene layers on stainless steel, was studied using a quartz crystal microbalance with dissipation (QCM-D). The experiments were performed both under good solvent conditions and above asphaltene precipitation onset. The adsorption/deposition of asphaltenes from model oil solution in xylene/n-hexane was found to strongly increase up to the asphaltene precipitation onset (i.e., ∼60–65 vol % n-hexane), with a 7–8 times increase of the adsorbed amount, compared with adsorption from xylene. Beyond the precipitation onset, the amount of asphaltene adsorbed/deposited decreases. Under both good solvent and precipitating conditions, the amphiphile was unable to form a protective layer on stainless steel to prevent asphaltene adsorption/deposition. However, the amphiphile exhibited an excellent ability to reduce asphaltene adsorption/deposition by 80–95 wt % when injected along with a...