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Understanding solvent effects on adsorption and protonation in porous catalysts.

ABSTRACT: Solvent selection is a pressing challenge in developing efficient and selective liquid phase catalytic processes, as predictive understanding of the solvent effect remains lacking. In this work, an attenuated total reflection infrared spectroscopy technique is developed to quantitatively measure adsorption isotherms on porous materials in solvent and decouple the thermodynamic contributions of van der Waals interactions within zeolite pore walls from those of pore-phase proton transfer. While both the pore diameter and the solvent identity dramatically impact the confinement (adsorption) step, the solvent identity plays a dominant role in proton-transfer. Combined computational and experimental investigations show increasingly favorable pore-phase proton transfer to pyridine in the order: water

SUBMITTER: Gould NS

PROVIDER: S-EPMC7044222 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Understanding solvent effects on adsorption and protonation in porous catalysts.

Gould Nicholas S NS Li Sha S Cho Hong Je HJ Landfield Harrison H Caratzoulas Stavros S Vlachos Dionisios D Bai Peng P Xu Bingjun B

Nature communications 20200226 1

Solvent selection is a pressing challenge in developing efficient and selective liquid phase catalytic processes, as predictive understanding of the solvent effect remains lacking. In this work, an attenuated total reflection infrared spectroscopy technique is developed to quantitatively measure adsorption isotherms on porous materials in solvent and decouple the thermodynamic contributions of van der Waals interactions within zeolite pore walls from those of pore-phase proton transfer. While bo ...[more]

PMID: 32103007

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