The Temperature-Programmed Desorption of H2 from Cu/ZrO2
| Autor: | Julian Schittkowski, Katharina Toelle, Martin Muhler, Darren Buesen |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Hydrogen
Chemistry Thermal desorption spectroscopy Thermal desorption Analytical chemistry chemistry.chemical_element 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Kinetic energy 01 natural sciences Catalysis 0104 chemical sciences Chemisorption Desorption Crystallite 0210 nano-technology |
| Zdroj: | Catalysis Letters. 146:1011-1017 |
| ISSN: | 1572-879X 1011-372X |
| Popis: | The desorption kinetics of hydrogen from a polycrystalline Cu/ZrO2 catalyst was investigated under atmospheric pressure using temperature-programmed desorption (TPD) experiments in a microreactor set-up. Different heating rates were applied under equal conditions with a carefully reduced catalyst. The hydrogen TPD peaks were symmetric and centered slightly above 300 K indicating associative desorption of H2 from metallic Cu. Using heating rate variation, the kinetic parameters $$A_{des}$$ and $$E_{des}$$ were determined to be 1.24 × 109 s−1 and 68 kJ mol−1, respectively. As the modeling with constant values of $$A_{des}$$ and $$E_{des}$$ yielded signals which were too narrow, dependence of $$E_{des}$$ on coverage was introduced applying $$E_{des} - K (\Theta _H)^n$$ . By application of the “full-analysis” method an optimal fit to the experimental data was found. Setting n = 1 resulted in the best fit and a value of 61 kJ mol−1 − (6.25 kJ mol−1 × $$\Theta _H$$ ) for $$E_{des}$$ was determined. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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