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Asphaltenes, resins and maltenes physical isolation procedures involving different alkane precipitants and solvent/sample ratios were applied in this work to Athabasca bitumen vacuum residue. Samples were characterized by Solubility Profiling, Size Exclusion Chromatography, Fluorescence Spectroscopy, X-ray Photoelectron Spectroscopy and density-viscosity analyses. Isolated fractions were found to display systematic property changes. Thus, it was found that denser, more polar, higher molecular weight (MW), more viscous, red shifted fluorescence materials were sequentially ranked as follows: Solvent extracted asphaltenes -C7 (unwashed) asphaltenes -C5 (unwashed) asphaltenes -resins -maltenes. Intermolecular aggregation for these fractions was determined to follow the same order. Decreasing contents of resins in the same order were found to increase aggregation phenomena.This work further reported on aspects of possible practical interest, i.e., the liquid nature of asphaltenes at 300°C and, possible existence of oxidative reactions affecting fractions isolation that follow standard methods which do not contemplate inert atmospheres. Preliminary assessment of chemical functionalities within isolated fractions highlighted on the possible enrichment of pyrrolic compounds within resins and oxygen functionalities in asphaltenes.

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Since 2002, the Steam Assisted Gravity Drainage (SAGD) production technique has had a skyrocketing growth in the province of Alberta, increasing production from 31,000 barrels per day (bpd) in 2002 up to 577,000 bpd by 2013. SAGD is a highly energy intensive method that consumes large quantities of natural gas and water for the production of steam. Once heavy oils are extracted – via SAGD – they must meet pipeline specifications in order to be commercialized, thus dilution with a higher value hydrocarbon or invest in a long-term upgrading project. One way of optimizing and integrating the extraction and upgrading of heavy oils is proposed with the development of the Dense Hot Fluid Injection (DHFI) process, a catalytic in situ upgrading technology. The process targets the substitution – at least partially – of steam by a high heat capacity fluid carrying to the reservoir heat, dispersed nanocatalyst, and hydrogen in order to generate a more competitive oil sand product. It targets the conversion of the vacuum residue (VR) fraction and generates an upgraded synthetic crude oil (SCO) with no vacuum residue and with pipeline transportable viscosity. In this work a two-dimensional bench scale plant is used for the experimental simulation of production and upgrading of an Athabasca type reservoir via DHFI processing. The arrangement is designed to study the heat distribution and oil production from a system with different permeabilities. VR is injected at different residence times to study its conversion levels, and a postmortem product mapping is performed to the residual oil left in the sand packed media. Results confirmed that important upgrading occurs at 500 psi, 350 °C, and hydrogen injection ratios of 300 sccm H2/cc VR. Under the most severe studied case, products reached API gravities of 16°API from a feedstock of 2.4°API. Extremely light hydrocarbons were found within high permeable areas of the rig, while the thermal distribution of the process confirmed the differences between steam injection, presenting “V” type chambers, and dense fluid injection with elliptical shape distributions.

Solvent deasphalting of the bottom of vacuum distillation columns (vacuum residue, VR) is a process practiced worldwide. In Northern Alberta, a solvent deasphalting plant was designed to process up to 4000 tons/day of the asphaltenic pitch. Asphaltenes oxy-cracking in liquid phase could be a new approach to asphaltenes upgrading and conversion into valuable chemicals. Oxy-cracking is a combination of oxidation and cracking in basic aqueous media at moderate temperatures (170–225 °C) and pressures (300–500 psi). This process could act very selectively producing smaller amounts of greenhouse gases like CO2, thus being considered environmentally friendly. In this work, a mild oxy-cracking treatment of C5-asphaltenes solid from Athabasca vacuum residue was investigated. The reaction kinetics and possible reaction mechanism for C5-asphaltenes oxy-cracking in water under alkali conditions were studied. Products solubilized under different severities were characterized using Fourier transform infrared and nuclear magnetic resonance spectroscopies, simulated distillation, elemental analysis, and ultraviolet–visible spectrophotometry to investigate the structure of solubilized products and changes in asphaltenes structures after the reaction. A model based on sequential-parallel reactions from the asphaltenes to water-soluble products and CO2 was found to describe the process successfully. Products of oxidized functionalities like carboxylic acids, their salts, methyl ethers and esters, and sulfur-oxidized forms plus phenolics were determined as the most significant fractions soluble in water. Solubilization of asphaltenes in water could also decrease challenges regarding facilities and pipelines plugging.