Removal of Fine Solids from Bitumen by Hetero-Aggregation and Magnetic Separation Using Surface-Modified Magnetite Nanoparticles. Part 1: Proof of Concept

Separation of fine particles suspended in liquid is crucial yet difficult and inefficient in various engineering processes. In the oil sands industry, high fine solids content in produced bitumen is one of the hurdles preventing non-aqueous extraction (NAE) from being used in commercial operations. This work proposed a novel method for fine solids removal from NAE bitumen by hetero-aggregation with surface-modified magnetite nanoparticles followed by magnetic separation. Stearylamine acetate-functionalized magnetite nanoparticles (SAA-MNPs) were prepared and characterized, and the separation performance of fine solids from NAE bitumen by the proposed approach using SAA-MNPs was quantitatively evaluated and compared with un-modified magnetite nanoparticles (MNPs). It is demonstrated that after functionalization with SAA, the separation effectiveness was significantly improved. Hetero-aggregates between the NAE fine solids and SAA-MNPs were shown to be formed in cyclohexane. The present work provided a promising approach of combining hetero-aggregation and magnetic separation for the purification of hydrocarbon products such as Alberta oil sands bitumen.