Enhanced Cometabolic Transformation of 4-Chlorophenol in the Presence of Phenol by Granular Activated Carbon Adsorption
Bibliographic record
Abstract
Substrate inhibitions that manifest within the cometabolism system of 4-chlorophenol (4-cp) and phenol were alleviated through the application of granular activated carbon (GAC) in batch biodegradation. It was found that 4-cp was preferentially adsorbed over phenol by the GAC and that 50% to 70% of the adsorption was achieved within the first two hours of contact. The kinetics of 4-cp adsorption was also much faster than that of phenol, even when the co-existing phenol was of a significantly higher initial concentration. As a result, competitive inhibition between the two compounds was minimized. Adsorption also caused a lowering of the phenol concentration in solution with a concomitant reduction in the substrate inhibition effect on cell growth. The addition of GAC benefited the biotransformation process through shortening the total degradation time for 600 mg L−1 phenol and 100 mg L−1 4-cp from 42 h to 12 h; and it also made it possible for cells to survive and transform 600 mg L−1 phenol and as high as 400 mg L−1 4-cp in free suspension cultures. Repeated operations in which GAC was reused showed that GAC could be regenerated by the cells, thus rendering the GAC incorporated process amenable to long term operations. Les inhibitions de substrat qui se manifestent dans le système de cométabolisme du chlorophénol-4 (cp-4) et du phénol ont été réduites par l'application de charbon actif granulaire (GAC) lors d'une biodégradation discontinue. On a trouvé que le cp-4 était le premier à être adsorbé sur le phénol par le GAC et que de 50 à 70 % de l'adsorption avait lieu dans les deux premières heures du contact. La cinétique d'adsorption du cp-4 est également beaucoup plus rapide que celle du phénol, même lorsque le phénol coexistant est d'une concentration initiale substantiellement plus élevée. En conséquence, l'inhibition compétitive entre les deux composés est minimisée. L'adsorption cause également une baisse de la concentration de phénol dans la solution avec une réduction concomitante de l'effet d'inhibition du substrat sur la croissance des cellules. L'ajout de GAC a un effet bénéfique sur le processus de biotransformation en raccourcissant le temps de dégradation total pour 600 mg L−1 de phénol et 100 mg L−1 de cp-4 de 42 h à 12 h; et cela permet également aux cellules de survivre et de transformer 600 mg L−1 de phénol et jusqu'à 400 mg L−1 de cp-4 en cultures de suspensions libres. Des opérations répétées dans lesquelles le GAC est réutilisé montrent que le GAC pourrait être régénérées par les cellules, rendant ainsi le procédé d'incorporation du GAS propice pour des opérations à long terme.
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".