Influence of Oil Sands Composition on Bitumen Quality During Non-Aqueous Bitumen Extraction from the Athabasca Deposit

The aim of the present work is to identify the most important species affecting a non-aqueous bitumen extraction process and bitumen quality. This investigation was carried out on four petrologic end member samples from Syncrude's North Mine collected in 2012 (NM12), i.e., marine claystone (MC), marine sand (MS), estuarine claystone (EC), and estuarine sand (ES). Each end member was separately mixed with cyclohexane at a ratio of 40:60 (cyclohexane:end member), and the bitumen-cyclohexane solutions were collected at different settling times (1-30 min). These solutions were analyzed to determine the amount, particle size distribution, and mineralogical composition of suspended fine solids (SFS), water content, as well as the bitumen content using a focused beam reflectance measurement (FBRM) particle size analyzer, Karl Fischer (KF) titration, x-ray diffraction (XRD), quantitative XRD (QXRD), and elemental analysis. The SFS was composed of mainly illite and kaolinite after cyclohexane extraction from MC, MS, EC, and ES. Although mixed layer expandable clay minerals (i.e., illite-smectite and kaolinite-smectite) were identified in the original clay, end members (EC and MC), illite-smectite, and kaolinite-smectite were not observed in the SFS of the bitumen-cyclohexane solutions obtained from the four petrologic end members. The SFS content and bitumen quality of the bitumen product were affected slightly but significantly by the end member composition and settling time, respectively. Illite and kaolinite were identified as the main minerals in the SFS of the bitumen products after relatively long settling times.