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Interzeolite conversion of a micronsized FAU to a nanosized CHA zeolite free of organic structure directing agent with a high CO₂ capacity.

ABSTRACT: The interzeolite transformation of a micronsized FAU zeolite to a nanosized CHA zeolite via alkali treatment is presented. The impact of the selection of the FAU zeolite starting material on the properties of the produced CHA zeolite was analyzed by XRD, ICP, SEM, TEM, N₂ and CO₂ adsorption, and in situ FT-IR. The analysis showed that the choice of starting FAU zeolite had a large impact on the chemical composition, size, morphology, and porosity of the produced CHA zeolite. The as prepared CHA samples show high capacity toward CO₂ (4.26 mmol g^-1) and it was demonstrated that the chemisorbed vs. physisorbed CO₂ was controlled by varying the amount of alkali cations in the CHA zeolite.

SUBMITTER: Moller KH

PROVIDER: S-EPMC9058122 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Interzeolite conversion of a micronsized FAU to a nanosized CHA zeolite free of organic structure directing agent with a high CO2 capacity.

Møller Kristoffer H KH Debost Maxime M Lakiss Louwanda L Kegnæs Søren S Mintova Svetlana S

RSC advances 20201125 70

The interzeolite transformation of a micronsized FAU zeolite to a nanosized CHA zeolite via alkali treatment is presented. The impact of the selection of the FAU zeolite starting material on the properties of the produced CHA zeolite was analyzed by XRD, ICP, SEM, TEM, N2 and CO2 adsorption, and in situ FT-IR. The analysis showed that the choice of starting FAU zeolite had a large impact on the chemical composition, size, morphology, and porosity of the produc ...[more]

PMID: 35514926

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