Liquid-Phase Hydrogenation of Maleic Acid over Pd/Al2O3 Catalysts Prepared via Deposition–Precipitation Method
Bibliographic record
Abstract
Succinic acid (SA) is a valuable raw material obtained by hydrogenation of maleic acid (MA). The product selectivity of this reaction is highly dependent on the reaction conditions. This study therefore investigated the effect of the reaction temperature, hydrogen pressure, and reaction time on the liquid-phase hydrogenation of MA by a Pd/Al2O3 catalyst. Complete conversion of MA and 100% selectivity for SA were achieved at a temperature of 90 °C, H2 pressure of 5 bar, and reaction time of 90 min. Fumaric acid (FA) was formed as an intermediate material by hydrogenation of MA under nonoptimal conditions. The impact of the percentage of Pd dispersion and phase of the Al2O3 support (γ, θ + α, and α) was also examined. The Pd/Al2O3 catalyst with 29.8% dispersion of Pd and γ phase of Al2O3 exhibited the best catalytic performance. Thus, catalytic activity depends not only on the amount of Pd dispersion but also on the physicochemical properties of Al2O3.
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) | 0.001 | 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".