Interaction forces between bitumen and clay minerals in oil sands liberation process at different solution environments.

The article focuses on investigating the interaction forces between bitumen and clay minerals in oil sands under various cationic solution environments to understand the challenges in bitumen liberation during extraction. Using atomic force microscopy (AFM) colloidal probe technology, the study characterizes the chemical structures and surface morphologies of bitumen and common clay minerals—silica, kaolinite, illite, and montmorillonite—and measures adhesion forces in distilled water and salt solutions containing monovalent and divalent metal cations. Results indicate that clay minerals exhibit stronger adhesion to bitumen than silica, with divalent cations (e.g., Ca²⁺) significantly increasing adhesion forces and jump-out distances, thereby reducing bitumen liberation efficiency by promoting surface coverage and altering hydrophobicity. These findings provide theoretical insights for improving flotation-based bitumen extraction from oil sands by addressing the effects of fine clay minerals and metal cations on bitumen recovery.