On the Location of Lewis Acidic Aluminum in Zeolite Mordenite and the Role of Framework-associated Aluminum in Mediating the Switch Between Brønsted and Lewis Acidity

Overview

Journal Chem Sci

Publisher Royal Society of Chemistry

Specialty Chemistry

Date 2021 Jun 24

PMID 34163680

Citations 7

Authors

Manoj Ravi

Vitaly L Sushkevich

Jeroen A van Bokhoven

Affiliations

Soon will be listed here.

Abstract

Lewis acidic aluminum in zeolites, particularly acidity that is inherent to the framework, is an indeterminate concept. A fraction of framework aluminum changes geometry to octahedral coordination in the proton form of zeolite mordenite. Such octahedrally coordinated aluminum is the precursor of a Lewis acid site and its formation is accompanied by a loss in Brønsted acidity. Herein, we show that such Lewis acid sites have a preferred location in the pore structure of mordenite. A greater proportion of these Lewis acid sites resides in the side-pockets than in the main channel. By reverting the octahedrally coordinated aluminum back to a tetrahedral geometry, the corresponding Brønsted acid sites are restored with a concomitant loss in the ability to form Lewis acid sites. Thereby, reversible octahedral-tetrahedral aluminum coordination provides a means to indirectly switch between Lewis and Brønsted acidity. This phenomenon is unique to Lewis acidity that is inherent to the framework, thereby distinguishing it from Lewis acidity originating from extra-framework species. Furthermore, the transformation of framework aluminum into octahedral coordination is decoupled from the generation of distorted tetrahedrally coordinated aluminum, where the latter gives rise to the IR band at 3660 cm in the OH stretching region.

Citing Articles

Evaluation of Zeolite Composites by IR and NMR Spectroscopy.

Dalena F, Dib E, Onida B, Ferrarelli G, Daturi M, Giordano G Molecules. 2024; 29(18).

PMID: 39339445 PMC: 11433990. DOI: 10.3390/molecules29184450.

Modulating acid sites in Y zeolite for valorisation of furfural to get γ-valerolactone.

Jayakumari M, Krishnan C RSC Adv. 2024; 14(30):21453-21463.

PMID: 38979450 PMC: 11228575. DOI: 10.1039/d4ra03113j.

The need for modelling of Al NMR in zeolites: the effect of temperature, topology and water.

Lei C, Erlebach A, Brivio F, Grajciar L, Tosner Z, Heard C Chem Sci. 2023; 14(34):9101-9113.

PMID: 37655014 PMC: 10466278. DOI: 10.1039/d3sc02492j.

The concept of active site in heterogeneous catalysis.

Vogt C, Weckhuysen B Nat Rev Chem. 2023; 6(2):89-111.

PMID: 37117296 DOI: 10.1038/s41570-021-00340-y.

Micro/mesoporous LTL derived materials for catalytic transfer hydrogenation and acid reactions of bio-based levulinic acid and furanics.

Antunes M, Silva A, Fernandes A, Ribeiro F, Neves P, Pillinger M Front Chem. 2022; 10:1006981.

PMID: 36247668 PMC: 9558274. DOI: 10.3389/fchem.2022.1006981.

References

Bui L, Luo H, Gunther W, Roman-Leshkov Y . Domino reaction catalyzed by zeolites with Brønsted and Lewis acid sites for the production of γ-valerolactone from furfural. Angew Chem Int Ed Engl. 2013; 52(31):8022-5. DOI: 10.1002/anie.201302575. View

Omegna A, Prins R, van Bokhoven J . Effect of temperature on aluminum coordination in zeolites H-Y and H-USY and amorphous silica-alumina: an in situ Al K edge XANES study. J Phys Chem B. 2006; 109(19):9280-3. DOI: 10.1021/jp050086o. View

Dedecek J, Tabor E, Sklenak S . Tuning the Aluminum Distribution in Zeolites to Increase their Performance in Acid-Catalyzed Reactions. ChemSusChem. 2018; 12(3):556-576. DOI: 10.1002/cssc.201801959. View

Yi X, Liu K, Chen W, Li J, Xu S, Li C . Origin and Structural Characteristics of Tri-coordinated Extra-framework Aluminum Species in Dealuminated Zeolites. J Am Chem Soc. 2018; 140(34):10764-10774. DOI: 10.1021/jacs.8b04819. View

Li X, Narayanan S, Michaelis V, Ong T, Keeler E, Kim H . Zeolite Y Adsorbents with High Vapor Uptake Capacity and Robust Cycling Stability for Potential Applications in Advanced Adsorption Heat Pumps. Microporous Mesoporous Mater. 2014; 201:151-159. PMC: 4226535. DOI: 10.1016/j.micromeso.2014.09.012. View

Brus J, Kobera L, Schoefberger W, Urbanova M, Klein P, Sazama P . Structure of framework aluminum Lewis sites and perturbed aluminum atoms in zeolites as determined by 27Al{1H} REDOR (3Q) MAS NMR spectroscopy and DFT/molecular mechanics. Angew Chem Int Ed Engl. 2014; 54(2):541-5. DOI: 10.1002/anie.201409635. View

Bhan A, Allian A, Sunley G, Law D, Iglesia E . Specificity of sites within eight-membered ring zeolite channels for carbonylation of methyls to acetyls. J Am Chem Soc. 2007; 129(16):4919-24. DOI: 10.1021/ja070094d. View

Vogt E, Weckhuysen B . Fluid catalytic cracking: recent developments on the grand old lady of zeolite catalysis. Chem Soc Rev. 2015; 44(20):7342-70. PMC: 4594121. DOI: 10.1039/c5cs00376h. View

Li S, Zheng A, Su Y, Fang H, Shen W, Yu Z . Extra-framework aluminium species in hydrated faujasite zeolite as investigated by two-dimensional solid-state NMR spectroscopy and theoretical calculations. Phys Chem Chem Phys. 2010; 12(15):3895-903. DOI: 10.1039/b915401a. View

10.

Dapsens P, Mondelli C, Perez-Ramirez J . Design of Lewis-acid centres in zeolitic matrices for the conversion of renewables. Chem Soc Rev. 2015; 44(20):7025-43. DOI: 10.1039/c5cs00028a. View

11.

Sartori G, Maggi R . Use of solid catalysts in Friedel-Crafts acylation reactions. Chem Rev. 2006; 106(3):1077-104. DOI: 10.1021/cr040695c. View

12.

van Bokhoven J, van der Eerden A, Koningsberger D . Three-coordinate aluminum in zeolites observed with in situ x-ray absorption near-edge spectroscopy at the Al K-edge: flexibility of aluminum coordinations in zeolites. J Am Chem Soc. 2003; 125(24):7435-42. DOI: 10.1021/ja0292905. View

13.

Ravi M, Sushkevich V, van Bokhoven J . Towards a better understanding of Lewis acidic aluminium in zeolites. Nat Mater. 2020; 19(10):1047-1056. DOI: 10.1038/s41563-020-0751-3. View

14.

Chen K, Horstmeier S, Nguyen V, Wang B, Crossley S, Pham T . Structure and Catalytic Characterization of a Second Framework Al(IV) Site in Zeolite Catalysts Revealed by NMR at 35.2 T. J Am Chem Soc. 2020; 142(16):7514-7523. PMC: 7269371. DOI: 10.1021/jacs.0c00590. View

15.

Grundner S, Markovits M, Li G, Tromp M, Pidko E, Hensen E . Single-site trinuclear copper oxygen clusters in mordenite for selective conversion of methane to methanol. Nat Commun. 2015; 6:7546. PMC: 4491810. DOI: 10.1038/ncomms8546. View

16.

Xin S, Wang Q, Xu J, Chu Y, Wang P, Feng N . The acidic nature of "NMR-invisible" tri-coordinated framework aluminum species in zeolites. Chem Sci. 2020; 10(43):10159-10169. PMC: 6979346. DOI: 10.1039/c9sc02634g. View

17.

Boronat M, Corma A . What Is Measured When Measuring Acidity in Zeolites with Probe Molecules?. ACS Catal. 2019; 9(2):1539-1548. PMC: 6369611. DOI: 10.1021/acscatal.8b04317. View

18.

Luo H, Lewis J, Roman-Leshkov Y . Lewis Acid Zeolites for Biomass Conversion: Perspectives and Challenges on Reactivity, Synthesis, and Stability. Annu Rev Chem Biomol Eng. 2016; 7:663-92. DOI: 10.1146/annurev-chembioeng-080615-034551. View

19.

Drake I, Zhang Y, Gilles M, Teris Liu C, Nachimuthu P, Perera R . An in situ Al K-edge XAS investigation of the local environment of H+- and Cu+-exchanged USY and ZSM-5 zeolites. J Phys Chem B. 2006; 110(24):11665-76. DOI: 10.1021/jp058244z. View

20.

Yu Z, Zheng A, Wang Q, Chen L, Xu J, Amoureux J . Insights into the dealumination of zeolite HY revealed by sensitivity-enhanced 27Al DQ-MAS NMR spectroscopy at high field. Angew Chem Int Ed Engl. 2010; 49(46):8657-61. DOI: 10.1002/anie.201004007. View