Characterization of NOx Species in Dehydrated and Hydrated Na- and Ba-Y, FAU Zeolites Formed in NO₂ Adsorption
Adsorbed ionic NOx species formed upon the interaction of NO₂ with dehydrated or hydrated Na-, and Ba-Y, FAU zeolites were characterized using FTIR/TPD, solid state NMR, and XANES techniques. NO₂ disproportionates on both dehydrated catalyst materials forming NO⁺ and NO₃⁻ species. These ionic species are stabilized by their interactions with the negatively charged zeolite framework and the charge compensating cations (Na⁺ and Ba²⁺), respectively. Although the nature of the adsorbed NOx species formed on the two catalysts is similar, their thermal stabilities are strongly dependent on the charge compensating cations. In the presence of water in the channels of these zeolite materials new paths open for reactions between NO⁺ and H₂O, and NO₂ and H₂O, resulting in significant changes in the adsorbed ionic species observed. These combined spectroscopic investigations afforded the understanding of the interactions between water and the NO₂ on these zeolite catalysts.
- Research Organization:
- Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 877539
- Report Number(s):
- PNNL-SA-42646; 6695; KC0302010
- Journal Information:
- Journal of Electron Spectroscopy and Related Phenomena, 150(2-3):164-170, Journal Name: Journal of Electron Spectroscopy and Related Phenomena, 150(2-3):164-170
- Country of Publication:
- United States
- Language:
- English
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