Molar Kinetics and Selectivity in Cracking of Athabasca Asphaltenes
Bibliographic record
Abstract
The thermal decomposition of Athabasca bitumen asphaltenes was investigated in the temperature range 350 to 430 °C. The cracking kinetics of the asphaltenes and their intermediates were analyzed on a total a molar basis, to avoid the assumptions inherent in lumped kinetic models. The apparent first-order activation energy was 176 kJ/mol over the temperature range. Reaction selectivity changed from evolution of hydrogen sulfide to evolution of hydrocarbon gases and liquids over the same range of temperature. This change was consistent with a shift of the controlling reaction mechanism from the cleavage of C−S bonds to the cleavage of C−C bonds as temperature increased past 400 °C. The formation of hydrocarbon gases was the dominant reaction on a molar basis at temperatures over 400 °C, therefore, these reactions require more attention in mechanistic models for cracking of heavy petroleum fractions.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".