The Cu migration of Cu-SAPO-34 catalyst for ammonia selective catalytic reduction of NOx during high temperature hydrothermal aging treatment
| Autor: | Huawang Zhao, Yingnan Zhao, Yongdan Li, Yuhan Ma, Xianghui Li, Hong Chen, Mengke Liu, Xin Yong |
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| Přispěvatelé: | Department of Chemical and Metallurgical Engineering, Tianjin University, Industrial chemistry, Aalto-yliopisto, Aalto University |
| Rok vydání: | 2019 |
| Předmět: |
Chemistry
One-pot synthesis chemistry.chemical_element Selective catalytic reduction 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Copper Catalysis Hydrothermal circulation 0104 chemical sciences Ammonia chemistry.chemical_compound Crystallite 0210 nano-technology NH selective catalytic reduction Hydrothermal treatment Cu-SAPO-34 zeolite One-pot synthesis Ion-exchange preparation ta215 NOx Nuclear chemistry |
| Zdroj: | Catalysis Today. 327:126-133 |
| ISSN: | 0920-5861 |
| Popis: | Two kinds of Cu-SAPO-34 catalysts, prepared with a one-pot technique using Cu- tetraethylenepentamine as co-template and an ion-exchange method, were hydrothermally treated at 750 °C for at least 16 h. The migration of Cu species during hydrothermal treatment and the corresponding effect on the selective catalytic reduction (SCR) of NOx were examined and characterized. A certain amount of CuO exists outside and inner the crystallites in the as prepared ion-exchanged sample, whereas copper is mainly atomically dispersed in the one-pot sample existing as isolated Cu2+. After hydrothermal treatment for 16 h, the amount of the inner nanosized CuO in the ion-exchanged sample reduced and the copper disperses to form more isolated Cu2+. However, surface CuO particles increase at the sacrifice of isolated Cu2+ with extending the hydrothermal treatment to 24 h. Aggregation of Cu2+ species also happens during the aging treatment over the one-pot prepared sample where the initial Cu is atomically dispersed as isolated Cu2+. The increase of the amount of the isolated Cu2+ enhances the low-temperature ( |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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