Solar photocatalytic degradation of model naphthenic acids mixtures by Bi2WO6 and Bi2WO6/NiO/Ag: Exploring the influence of inorganic fraction of oil sands process water
Bibliographic record
Abstract
• Bi 2 WO 6 /NiO/Ag was most efficient at degrading NAs in buffer and OSPW-IF. • Chloride and bicarbonate ions inhibited the degradation of most NAs in the mixture. • NO 3 – photosensitization formed aminyl radicals and speed up IA degradation. • Frontier molecular orbital calculations identified initial reaction sites. This study investigates the comparative photocatalytic degradation of six model naphthenic acids, key organic constituents responsible for the toxicity of oil sands process water, using the semiconductor photocatalysts Bi 2 WO 6 and Bi 2 WO 6 /NiO/Ag in both buffered solution and the inorganic fraction of OSPW. The heterojunction catalyst (Bi 2 WO 6 /NiO/Ag) exhibited the highest removal efficiencies for these organic pollutants with k values 0.048, 0.036, 0.019, 0.283, 0.026, and 0.075 min −1 for 1-adamantanecarboxylic acid, cyclohexanecarboxylic acid, tetrahydropyran-4-carboxylic acid, tetrahydro-2H-thiopyran-4-carboxylic acid, isonipecotic acid, and 4,5-dihydronaphtho[1,2-b]thiophene-2-carboxylic acid, respectively. Experimental analysis suggested that chloride and bicarbonate inhibited the photocatalytic degradation of the target naphthenic acids, while nitrate could accelerate the production of aminyl radicals, enhancing the degradation of isonipecotic acid. Notably, four additional nitrated and hydroxylated by-products were identified during 1-adamantanecarboxylic acid degradation in the presence of nitrate. The addition of the catalyst not only accelerated the degradation rate of 1-adamantanecarboxylic acid but also helped mitigate the formation of potentially toxic by-products. Additionally, the transformation products of 4,5-dihydronaphtho[1,2-b] thiophene-2-carboxylic acid were identified. Degradation pathways were further elucidated with the assistance of density functional theory calculations, identifying the β-carbon as the initial reactive site, with the sulfur atom also playing a significant role in reactivity. These findings contribute to the understanding of the water matrix-induced transformation process of model naphthenic acids during photocatalytic treatment, enhancing the environmental applicability of photocatalytic treatments.
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 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".