Mechanism of Zr Incorporation in the Course of Hydrothermal Synthesis of Zeolite BEA | Sciact - CRIS-system of Boreskov Institute of Catalysis

Mechanism of Zr Incorporation in the Course of Hydrothermal Synthesis of Zeolite BEA Full article

Journal

Inorganic Chemistry
ISSN: 0020-1669 , E-ISSN: 1520-510X

Output data

Year: 2018, Volume: 57, Number: 19, Pages: 11978-11985 Pages count : 8 DOI: 10.1021/acs.inorgchem.8b01548

Tags

LEWIS-ACID SITES; MEERWEIN-PONNDORF-VERLEY; BETA-ZEOLITE; CRYSTALLIZATION MECHANISM; ZR; BEA ZEOLITES; ALL-SILICA; ETHANOL; VALEROLACTONE; ISOMERIZATION; REDUCTION

Authors

Kots Pavel A. ¹ , Zabilska Anna V. ¹ , Khramov Evgeny V. ² , Grigoriev Yuriy V. ^2,3 , Zubavichus Yan V. ² , Ivanova Irina I. ^1,4

Affiliations

1	Department of Chemistry, Lomonosov Moscow State University
2	National Research Center “Kurchatov Institute”
3	Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” RAS
4	A.V. Topchiev Institute of Petrochemical Synthesis RAS

The mechanism of Zr-BEA hydrothermal synthesis in fluoride media has been investigated through the detailed characterization of samples obtained at different synthesis times by XRD, XRF, TGA, multinuclear solid-state NMR, FTIR, SEM, TEM with EDS, XAS, and nitrogen sorption. The synthetic procedure involved hydrothermal crystallization of the gel with the following composition: 1SiO2:0.54TEAOH:0.54HF:0.005ZrO2:5.6H2O. The formation of open and closed Lewis acid sites was monitored by FTIR spectroscopy of adsorbed CO, while coordination of Zr was studied by XAS. The results show that the formation of Zr-BEA proceeds by two steps. In the first step, pure silica BEA is crystallized via a solid–solid hydrogel rearrangement mechanism. Zirconium species are occluded in Si-BEA crystals in the form of Zr-rich silicate particles. These particles do not provide for any appreciable Lewis acidity. In the second step, Zr incorporation into T positions of the zeolite structure takes place, leading to the formation of closed Zr sites, which are partially converted into open sites at longer synthesis times. It is demonstrated that the content of open and closed sites can be tuned by variation of the synthesis time.

Kots P.A. , Zabilska A.V. , Khramov E.V. , Grigoriev Y.V. , Zubavichus Y.V. , Ivanova I.I.
Mechanism of Zr Incorporation in the Course of Hydrothermal Synthesis of Zeolite BEA
Inorganic Chemistry. 2018. V.57. N19. P.11978-11985. DOI: 10.1021/acs.inorgchem.8b01548 WOS Scopus РИНЦ ANCAN OpenAlex

Submitted:	Jun 5, 2018
Published online:	Sep 11, 2018
Published print:	Oct 1, 2018

Web of science:	WOS:000446413200017
Scopus:	2-s2.0-85053558352
Elibrary:	35724360
Chemical Abstracts:	2018:1678797
Chemical Abstracts (print):	169:353676
OpenAlex:	W2890466040

DB	Citing
Web of science	24
Scopus	27
OpenAlex	28