Separation of Petroporphyrins from Asphaltenes by Chemical Modification and Selective Affinity Chromatography
Bibliographic record
Abstract
Part of the metalloporphyrin fraction was separated from asphaltenes by a combination of reactive modification and affinity chromatography. The targeted vanadyl porphyrin complexes were modified by reaction with oxalyl chloride followed by a long chain alkylamine or perfluoroalkylaniline to produce an imido vanadium(IV) derivative bearing an octadecyl or perfluoroctyl side chain. This derivatized asphaltene was then chromatographed on C 18 -silica gel or perfluorous (-C 8 F 17 ) silica gel to remove the tagged metalloporphyrins from the remaining asphaltene. With the C 18 -tagging and reverse-phase chromatography method, from 15 to 40% of the total vanadium content together with comparable percentages of nickel was removed, with less than 5% mass loss from the asphaltene fraction. The fluorous tagging process gave better removal of metals on one sample but was limited by the lower recovery of asphaltenes on other samples. This approach requires further optimization for quantitative selective separation of metal complexes from heavy oils and to overcome the aggregation of the metals with other components of the asphaltenes.
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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".