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Study of Water Adsorption on EDTA-Modified LTA Zeolites.

ABSTRACT: The present work deals with the study of water adsorption on acid-modified zeolites A. Commercial zeolites 4A (Na form) and 5A (Ca form) were subjected to EDTA dealumination, and their structure, textural properties and stability were checked by XRD, EDX, NMR and N2 physisorption analyses. The water adsorption isotherms of the parent zeolites and their modified forms were measured at a temperature of 25 °C and up to a relative pressure of 0.9. The results show that the treatment with EDTA drastically changes the structural properties of the zeolites and increases the water adsorption capacity by up to 10%. The changes depend on the type of extra-framework cations (Na+ and Ca2+) and the EDTA concentration.

SUBMITTER: Volavsek J

PROVIDER: S-EPMC9027755 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Study of Water Adsorption on EDTA-Modified LTA Zeolites.

Volavšek Janez J Pliekhov Oleksii O Pliekhova Olena O Mali Gregor G Zabukovec Logar Nataša N

Nanomaterials (Basel, Switzerland) 20220414 8

The present work deals with the study of water adsorption on acid-modified zeolites A. Commercial zeolites 4A (Na form) and 5A (Ca form) were subjected to EDTA dealumination, and their structure, textural properties and stability were checked by XRD, EDX, NMR and N<sub>2</sub> physisorption analyses. The water adsorption isotherms of the parent zeolites and their modified forms were measured at a temperature of 25 °C and up to a relative pressure of 0.9. The results show that the treatment with ...[more]

PMID: 35458059

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