FES Funded ProjectsOutputs
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| Partial Upgrading During Froth Treatment: A Possible Dream?Poster presentation to the FES Research to Real World - Industrial MixerT08-P02 University of Alberta | Activity | 2020-02-20 | De Klerk, A., Joao Felipe Pereira Bassane, Natalia Montoya Sanchez | | Hydrothermal treatment of bitumen froth diluted with kerosenePoster presentation to the FES Digital Research Showcase.T08-P02 University of Alberta | Activity | 2020-11-23 | | | Potential for Partial Upgrading by Thermal Treatment of Bitumen FrothOral presentation to the ACS Spring 2021 conference.T08-P02 University of Alberta | Activity | 2021-04-07 | | | Visbreaking of Bitumen Froth: Influence of Minerals, Water, and Solvent on the Physicochemical Changes in the Bitumen PhaseThermal treatment of oil sand bitumen froth has the goal of not only improving the separation process during froth treatment but also accomplishing bitumen upgrading. There is evidence that both water and minerals have an effect on the physicochemical transformations that take place during the treatment. However, little is known about the nature of these transformations and whether the presence of mineral solids and water can be beneficial. The current study investigated the visbreaking of froth at 400 °C with an average equivalent residence time of 30 min. The froth elements (mineral solids and water) were either separated or maintained in the mixture to assess their effects during visbreaking. Visbreaking was performed in the absence and presence of hydrocarbon solvents (n-hexane and kerosene). Viscosity, density, refractive index, elemental composition, persistent free radical content, and nature of the hydrogen and carbon content were evaluated before and after the treatment. The products from froth visbreaking on a solvent-free bitumen basis had a kinematic viscosity in the range 1–4 × 103 mm2/s at 7.5 °C and a density in the range 990–1000 kg/m3 at 15.6 °C. When visbreaking was performed in the presence of n-hexane, the products had a lower increase in aromatic C, lower viscosity, and lower density on solvent-free basis compared to the products from visbreaking performed in kerosene or without a solvent. The presence of mineral solids and/or water during bitumen visbreaking consistently yielded a bitumen product with numerically higher viscosity and density compared with visbreaking of bitumen alone. Mineral solids and water affected hydrogen transfer reactions during visbreaking, which could be seen in terms of the relative change in the aromatic H and C content in the products. When mineral solids were present, some products were adsorbed on the solids, which also affected the H/C and free radical contents of the liquid product.T08-P02 University of Alberta | Publication | 2023-08-04 | | | Hydrothermal Treatment of Oilsands Bitumen Froth at 400 °C: Influence of Minerals and Water on Hydrogen Transfer, Cracking, and Addition ReactionsFollowing prior evidence that water and mineral solids influenced the physicochemical properties of the products derived from the visbreaking of bitumen froth at 400 °C, the present study aimed to explore the effect of water and minerals on the reaction chemistry taking place during the thermal conversion of froth. The current study investigated the relative impact of water and mineral solids on hydrogen transfer, cracking, and addition reactions during the thermal treatment of froth at 400 °C. α-Methylstyrene (AMS) was employed as a probe molecule, and selected chemical species identified in the feed and thermally converted products were monitored. Water had a major effect on suppressing the conversion of AMS, whereas the hindrance of AMS conversion by mineral solids seemed to be minor. Substantial evidence of hydrogen and methyl transfer, hydration, and addition reactions was observed through the formation of specific AMS-derived products. The potential free radical and cationic pathways for the conversion of AMS were evaluated based on the product composition of the different reaction systems. There was an indication that the availability of hydrogen donors also influenced the conversion pathways of AMS. Both water and mineral solids favored the extent of hydrogen transfer during the treatment. However, their specific effect on promoting transfer hydrogenation could not be determined. AMS was not a good probe for cracking under the conditions of this study. Evidence of hydration was observed in the water-containing systems. The presence of water suppressed the formation of addition products, resulting in an overall formation of these products that was half of that observed in the absence of water. The presence of minerals during the treatment seemed to have a minor impact on the selectivity profile of addition products, although it had no apparent influence on the overall formation of these products.T08-P02 University of Alberta | Publication | 2024-01-04 | | | Hydrothermal Treatment of Bitumen Froth: Impact of Mineral Solids and Water on Bitumen PropertiesHydrothermal treatment, i.e., thermal treatment of bitumen in the presence of water and solids, as a potential approach for combined froth treatment and upgrading was investigated in this work. Reactions were performed in batch reactors at 250 °C with the bitumen, water, and solid phases separated from industrially obtained bitumen froth, and the impact of the presence or absence of water
and/or solids on the bitumen conversion was studied. Statistical analysis of bitumen properties revealed that the hydrothermal treatment of the bitumen froth at 250 °C did not lead to upgrading of the bitumen. Treatment at the conditions used in this study was beneficial only when the bitumen was converted on its own. Water and/or mineral solids contributed to an increase in viscosity, which
was accompanied by an increase in free radical content. These observations were tentatively explained based on the generation of free radicals by redox reactions and heavier product formation promoted by free radical addition reactions. While the treatment did not significantly impact the density of bitumen, changes in the H/C ratio, n-heptane insoluble content, and metal content of bitumen were noted. The total acid number (TAN) of bitumen increased in the presence of water and mineral solids. Base catalyzed hydrolysis of esters and anhydrides in bitumen might be responsible for the increase in TAN, and the solids and water appeared to promote these reactions.T08-P02 University of Alberta | Publication | 2021-10-25 | | | Viscosity Mixing Rules for Bitumen at 1-10 wt % Solvent Dilution When Only Viscosity and Density Are KnownT08-P02 University of Alberta | Publication | 2020-06-01 | | | Free Radical and Cationic Addition due to Clay Minerals Found in Bitumen Froth at 250 °C Probed with Use of α-Methylstyrene and 1-OcteneFollowing previous evidence that hydrothermal treatment of bitumen froth does not lead to bitumen upgrading at 250 °C and promotes viscosity increase, the current study explores the free radical and cationic reactivity of clay minerals found in bitumen froth in promoting heavier material formation through addition reactions. The current investigation employed α-methylstyrene (AMS) and 1-octene as probe molecules instead of bitumen froth, and their conversion at 250 °C in the presence of clay minerals kaolinite and illite was studied in batch reactors. Thermal conversion of AMS and 1-octene at 250 °C in the absence of minerals was observed to be low. In the presence of clay minerals, not only the conversion of AMS and 1-octene was increased but also reactions such as dimerization of AMS and alkylation of 1-octene and toluene (used as solvents) were mainly promoted, leading to heavier product formation. Double-bond isomerization of 1-octene and cumene formation from AMS was side reactions that were also promoted by the clay minerals. Suppression of mineral-related conversion by pyridine and selectivity to different reaction products that enabled differentiation between free radical and cationic reaction pathways indicated that the mineral-related conversion was predominantly cationic in nature. Using the reactions in the presence of minerals and pyridine as surrogates for alkaline bitumen froth, it was concluded that even under alkaline conditions, minerals could promote heavier material formation through cationic addition.T08-P02 University of Alberta | Publication | 2022-11-09 | | | Thermal Treatment of Bitumen Froth at a Temperature of 250 °C and the Role of Clay Minerals in this ProcessBitumen is recovered from mined oil sands using a hot water extraction process, the product of which is called bitumen froth. Bitumen froth is a mixture of about 60 wt% bitumen, 30 wt % water and 10 wt% mineral solids. The bitumen in bitumen froth needs to be separated from the water and solids to convert it into a marketable bitumen product. To achieve this, solvent-based froth treatment processes are employed in the industry, which are operated at temperatures in the range 30-85 °C. An alternate approach, called hydrothermal treatment, which involves direct heating of bitumen froth without solvent addition was investigated in this work. Two studies were conducted, one to empirically evaluate the potential benefit of hydrothermal froth treatment, and one to investigate the role of mineral matter in the conversion process. Results indicated that hydrothermal froth treatment at 250 °C did not lead to the upgrading of the bitumen, and that thermal conversion of bitumen at the study conditions was beneficial only when the bitumen was treated on its own. Viscosity was one of the characteristic properties of bitumen measured in this work, and it was found that the presence of water and/or mineral solids during thermal conversion led to an increase in the viscosity of bitumen. These viscosity changes were accompanied by an increase in the free radical concentration in bitumen. It was hypothesized that the minerals, especially clays, might be responsible for promoting heavier material formation through free radical and/or cationic addition reactions. To test this hypothesis, the conversion of probe molecules α-methylstyrene (AMS) and 1-octene, instead of bitumen froth, at 250 °C was studied in the presence of the clay minerals kaolinite and illite, which are predominantly found in bitumen froth. While pure thermal conversion of AMS and 1-octene in the absence of minerals was noticed to be low, the conversion increased in the presence of the clay minerals. The minerals promoted heavier product formation through dimerization of AMS and alkylation of 1-octene and toluene (used as solvent), which were identified as the major reactions. The clay minerals also promoted formation of cumene from AMS and double bond isomerization of 1-octene, which were the side reactions. Additional reactions conducted in the presence of clay minerals and pyridine were used as surrogates for alkaline bitumen froth and to differentiate between free radical and cationic pathways. It was concluded that minerals could promote heavier material formation even under alkaline conditions, and that the mineral related conversion was primarily cationic in nature (Figure 1).
Figure 1. Cationic Conversion in the Presence of Clay Minerals
T08-P02 University of Alberta | Activity | 2023-02-14 | |
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