Cu-ZSM-5 Catalyst Synthesis via Ion-Exchange with Ammonia Solution of Copper Hydroxysalts Full article
| Journal |
Microporous and Mesoporous Materials
ISSN: 1387-1811 , E-ISSN: 1873-3093 |
||
|---|---|---|---|
| Output data | Year: 2024, Volume: 367, Article number : 112966, Pages count : 19 DOI: 10.1016/j.micromeso.2023.112966 | ||
| Tags | Cu-ZSM-5; Copper-ammonia complex; Copper dihydroxycarbonate; Copper trihydroxynitrate; DeNOx | ||
| Authors |
|
||
| Affiliations |
|
Funding (1)
| 1 | Ministry of Science and Higher Education of the Russian Federation | FWUR-2024-0033 |
Abstract:
The properties of dihydroxycarbonate (malachite) and trihydroxynitrate of copper were studied in order to apply their ammonia solutions for the synthesis of copper-substituted ZSM-5 zeolites. Copper concentration and NH4OH/Cu2+ ratio in the solutions varied 1–12 g/l and 6–30, respectively. The parameters of Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherms revealed the favorability of the chosen conditions and the chemical nature of [Cu(NH3)n]2+ ions sorption by zeolite. For both copper salts, the sorption capacity of H-ZSM-5 for Cu2+ ions was higher in the solutions having NH4OH/Cu2+ = 6–10 compared to 30. To identify the synthesis and structure – activity relationship correlations, the ammonia solution and Cu-ZSM-5 samples were characterized by EPR, UV–visible spectroscopy, temperature-programmed reduction by hydrogen (H2-TPR). The calcined Cu-ZSM-5 samples produced at NH4OH/Cu2+ = 6–30 contained two types of the isolated Cu2+ ions (bare Cu2+ and [Cu(OH)]+), differing in their Redox properties. Their reducibility improved with an increase in the copper loading and with a decrease in NH4OH/Cu2+. At NH4OH/Cu2+ = 6–10, the samples additionally comprised the structures of Cu2+ ions with extra-lattice oxygen (ELO), which were formed due to hydrolysis of [Cu(NH3)n(H2O)]2+ to [Cu(NH3)n(OH)]+ and then to [Cu(OH)2Cu]2+. Cu2+–ELO structures possessed a greater ability to complete reduction than both types of isolated Cu2+ ions. Correlations with DeNOx properties in selective catalytic reduction (SCR) of NO by propane and ammonia are discussed.
Cite:
Yashnik S.A.
, Surovtsova T.A.
, Salnikov A.V.
Cu-ZSM-5 Catalyst Synthesis via Ion-Exchange with Ammonia Solution of Copper Hydroxysalts
Microporous and Mesoporous Materials. 2024. V.367. 112966 :1-19. DOI: 10.1016/j.micromeso.2023.112966 WOS Scopus РИНЦ AN OpenAlex
Cu-ZSM-5 Catalyst Synthesis via Ion-Exchange with Ammonia Solution of Copper Hydroxysalts
Microporous and Mesoporous Materials. 2024. V.367. 112966 :1-19. DOI: 10.1016/j.micromeso.2023.112966 WOS Scopus РИНЦ AN OpenAlex
Dates:
| Submitted: | Oct 3, 2023 |
| Accepted: | Dec 24, 2023 |
| Published online: | Dec 29, 2023 |
| Published print: | Mar 1, 2024 |
Identifiers:
| Web of science: | WOS:001158911000001 |
| Scopus: | 2-s2.0-85182510591 |
| Elibrary: | 64941323 |
| Chemical Abstracts: | 2024:145335 |
| OpenAlex: | W4390413797 |