Synthesis of Ru‐silica aerogel as efficient catalyst for hydrogenation of p‐phenylenediamine to 1,4‐cyclohexanediamine
Bibliographic record
Abstract
Tetraethylorthosilicate (TEOS) and methyl trimethoxysilane (MTMS) were used as raw materials to prepare an Ru‐silica aerogel catalyst by sol‐gel and the supercritical drying method. The catalyst was characterized by various techniques including BET, TEM, FTIR, SEM, XPS, XRD, TG, and EDS. It was used for the hydrogenation of p‐phenylenediamine (PDA) to 1,4‐cyclohexanediamine (CHDA). The effect of various parameters, such as loading methods, catalyst components, catalyst amount, and the reaction time were systematically investigated. It was found by XPS that supercritical ethanol can convert Ru 3+ to Ru 0 by its strong reducing property. The catalyst prepared by sol‐gel and the supercritical drying method is homogeneous, with high loading rates and a high specific surface area above 700 m 2 /g. The reactivity of the catalyst prepared by the sol‐gel method is much higher than that prepared by the impregnation method. The PDA conversion of 99 % alone with the CHDA selectivity of 64 % were achieved under the reaction temperature of 150 °C and the pressure of 5 Mpa for 1 h. The PDA conversion decreased as the MTMS ratio increased in the catalyst. The anti‐cis ratio of CHDA reached the maximum value (2.25) when the ratio of MTMS/ TEOS was 2/3.
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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 | 0.001 |
| 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".