NIR hyperspectral investigation of extraction kinetics of ionic-liquid assisted bitumen extraction

The use of room temperature ionic liquids (IL) to assist bitumen extraction from oil sands in a waterless process was investigated. Four ILs were selected according to their ability to meet industrial requirements. Their impact on bitumen recovery and bitumen quality (fines content) was assessed through a mixed-level experimental design accounting for temperature, contact time, solvent-to-oil sands ratio, IL-to-oil sands ratio, water-to-IL ratio, solvent and IL types. In parallel, an innovative through-flow microcell coupled to near infrared spectroscopy (NIR) was developed to monitor on-line the IL-assisted bitumen extraction kinetics along with a quantitative reconstruction strategy using projection to latent structure (PLS) method. The choice of solvent rather than IL was the main impacting factor on bitumen recovery while the NIR extraction kinetic tests revealed that IL viscosity drastically reduced the rate constant of bitumen recovery. However, ILs were significant in capturing fines from bitumen with [EtNH3][NO3] as the best candidate.