Understanding the atomic-scaled evolution mechanism of V and Cr in V slag with high Cr content during magnesiation roasting toward tailing toxicity minimization
Bibliographic record
Abstract
V slag with high Cr content (VS-HCC) serves as the primary raw material for extracting V, and the evolution mechanism of V and Cr in VS-HCC decides the eco-friendliness of V extraction process. To minimize the Cr(VI) and residual V(V) content in tailings produced after V extraction, this work introduces the "atomic atmosphere" method to investigate the evolution mechanism of V and Cr in VS-HCC during magnesiation roasting at the atomic scale. In the early stage of roasting at 900℃, the FeV 2 O 4 and FeCr 2 O 4 spinel disappear and are converted into Fe 2 O 3 •V 2 O 3 and (Fe 0.6 Cr 0.4 ) 2 O 3 , with the chemical states of V and Cr unchanged; Fe 2 TiO 4 spinels are oxidized to generate FeTi 2 O 5 . After roasting for 10 min, Fe 2 SiO 4 structure is completely destroyed. Both the conversion of spinels and the complete decomposition of Fe 2 SiO 4 have created favorable conditions for the oxidation of V-bearing phases. After roasting for 50–90 min, V atoms transitioned from the mixed valence states (V 4 + /V 5+ ) to V 5+ . This transformation involved the combination of Mg 2+ , O 2- V 5+ and Mn 2+ ions, resulting in the formation of Mg 2 V 2 O 7 and Mn 2 V 2 O 7 crystals. Meanwhile, Cr atoms still exist as nontoxic Cr 3+ in the form of (Fe 0.6 Cr 0.4 ) 2 O 3 , ensuring the eco-friendliness of the magnesiation roasting of VS-HCC.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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 source (direct Gemma or distilled Codex), 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".