A nonaqueous process was developed using ionic liquids (ILs) to extract bitumen from Alberta oil sands at room temperature. Based on an IL design platform of balancing lipophilic/hydrophilic properties with possible interfacial interactions, trialkylamine/fatty acid-based ILs were studied and down-selected considering performance, cost, composition, and interaction with water. The use of protic ILs also allowed modifying the amine/acid composition to increase the bitumen extracted and decrease the solid content in extracted bitumen. Using the IL trioctylammonium oleate ([HN888]­[Oleate]) at a 1:3 IL/oil sand mass ratio, we were able to achieve bitumen extraction from high-grade Alberta oil sands of ca. 100% with low solids content (<1%) in a fast, low-energy process. Our results demonstrate that the proper design of the IL can lead to efficient oil extraction without conventional solvents, without generating aqueous tailings, and with minimum energy consumption, that is, a production process with environmental impacts comparable to those associated with production of other hydrocarbon resources.

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Exploitation of mineable oil sands in Canada has thus far produced over 50 km 2 of tailings in ponds where the fine solids remain suspended for years, even decades. These ponds represent a major liability and environmental burden for operating companies, with their dewatering critical to their remediation. In this work, we used the chemistry of the tailing pond constituents to design an ionic liquid (IL) for dewatering the mature fine tailings (MFT), taking advantage of the ability to introduce unique and different functionalities into each ion of the IL. We chose a class of protic ILs whose ions will interact with the solids while rejecting water. As an example, octylammonium oleate can be used to remove more than 70% of the water from MFT. The nature of the ILs makes their use amenable to a variety of large-scale separation techniques allowing engineering versatility in the design of the final process.