Insight into the efficient oxidation of methyl-ethyl-ketone over hierarchically micro-mesostructured Pt/K-(Al)SiO2 nanorod catalysts: Structure-activity relationships and mechanism
| Autor: | Chi He, Mingjiao Tian, Stuart Hamilton Taylor, Zhenxing Shen, Mudi Ma, Nicholas Dummer, Zeyu Jiang, Jian-Wen Shi, Zhengping Hao, Chunyan Ma |
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| Rok vydání: | 2018 |
| Předmět: |
chemistry.chemical_classification
Ketone Process Chemistry and Technology 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Catalysis 0104 chemical sciences Silanol chemistry.chemical_compound Adsorption chemistry Chemical engineering Catalytic oxidation Nanorod 0210 nano-technology Brønsted–Lowry acid–base theory Selectivity General Environmental Science |
| Zdroj: | Applied Catalysis B: Environmental. 226:220-233 |
| ISSN: | 0926-3373 |
| DOI: | 10.1016/j.apcatb.2017.12.007 |
| Popis: | Hierarchically micro-mesostructured Pt/K-Al-SiO2 catalysts with regular nanorod (Pt/KA-NRS) and spherical nanoflower-like (Pt/KA-SNFS) morphologies were prepared. The existence of Al atoms generates Brønsted acid sites and reduces silanol groups over the supports, promoting the dispersion of Pt nanoparticles and stability of catalysts. Potassium atoms balance the negative charge of supports and enhance O2 mobility. The Pt/KA-NRS catalysts exhibit unexceptionable low temperature activity, CO2 selectivity, and stability for MEK oxidation. Amongst, 0.27 wt.% Pt/KA-NRS completely converts MEK at just 170 °C (activation energy as low as 37.22 kJ·mol−1), more than 100 °C lower than other typical Pt/Pd supported catalysts reported in the literature. Diacetyl and 2,3-butandiol are the main intermediates during MEK activation, which convert into H2O and CO2 through aldehydes and acids. The excellent catalytic activity of Pt/KA-NRS is ascribed to their regular morphology, high Pt0 content and dispersion, excellent MEK adsorption capacity and superior O2/CO2 desorption capability under low temperature. |
| Databáze: | OpenAIRE |
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