In‐situ asphaltene capture with iron oxide nanoparticles in steam‐assisted gravity drainage ( <scp>SAGD</scp> ) for improved recovery and partial upgrading of bitumen

Abstract Nanoparticles have emerged as promising additives to enhance steam‐assisted gravity drainage (SAGD) efficiency by improving heat transfer, reducing viscosity, and promoting asphaltene adsorption and catalytic upgrading. This study integrates iron oxide (Fe 3 O 4 ) nanoparticles into the SAGD process to simultaneously improve oil recovery and partially upgrade bitumen via in‐situ asphaltene capture. Four nanoparticle‐assisted SAGD experiments were conducted, varying nanoparticle concentrations (1000, 3000, and 5000 mg/kg of porous media) and spatial distribution, and were compared against a baseline SAGD scenario. Fe 3 O 4 nanoparticles, synthesized via co‐precipitation, were selected for their high adsorption affinity for asphaltenes. Thermal performance was assessed through temperature distribution and thermogravimetric analysis (TGA), while recovery efficiency was evaluated by oil production and the cumulative steam–oil ratio (cSOR). Oil quality was analyzed using asphaltene content, carbon–hydrogen–nitrogen–sulphur (CHNS) elemental analysis, high‐resolution proton nuclear magnetic resonance ( 1 H NMR), matrix‐assisted laser desorption/ionization–time of flight (MALDI‐TOF), and rheological measurements. Uniformly dispersed 1000 ppm nanoparticles reached the highest recovery (83%), uniform heat flux, and the greatest asphaltene retention, with an asphaltene retention index (IR) of 0.23. Nanoparticle‐assisted oil exhibited reduced high‐molecular‐weight species, partial breakdown of heavy hydrocarbons, lower viscosity, and weakened asphaltene networks. These results showed that Fe 3 O 4 nanoparticles enhance heat transfer and selectively adsorb asphaltenes under SAGD conditions. Recovery was improved by enabling uniform spatial distribution, while oil quality benefited from appropriate nanoparticle concentration, highlighting the need to control both placement and dosage for optimal outcomes. Optimizing both the spatial distribution and concentration of Fe 3 O 4 nanoparticles maximizes SAGD recovery and upgrades the produced oil via in‐situ asphaltene adsorption.