Separation and Characterization of Non Humic Organic Matter Strongly Bound to Oil Sands Solids(Abstract)

摘要

While toluene insoluble organic matter (TIOM) is found in all oil sands particle size fractions it is particularly associated with finer materials. Previous surface characterization work on the TIOM indicates that this organic matter is best represented by a layered structure. Humic matter is adsorbed directly onto the mineral surfaces while the outer layer is derived from bitumen components. Depending on amount adsorbed, the organic matter increases oil wettability of solids and this may adversely affect the release of bitumen from the oil sands. The finest oil wettable particles remain with the oil phase after bitumen separation. Some of this solid material is carried over from the coking operation to downstream operations where it is involved in fouling of process units. In this work we use supercritical fluid extraction with methanol to selectively remove the non-humic TIOM from several oil sands with different bitumen recovery profiles. After removal from the solids the methanol extract (ME) is soluble in common organic solvents for bitumen. This allows for a detailed analysis of the ME in comparison with various fractions separated from bitumen by a modified high performance liquid chromatography (HPLC) procedure. Number average molecular weights for the methanol extracts are close to those for resins separated from bitumen. Only minor differences exist between ME and the resins in terms of H/C atomic ratios and aromaticities.