Mechanochemically assisted hydrothermal synthesis of Sn-substituted MFI-type silicates

Substitution of Al atoms in a zeolite framework by catalytic metal atoms has attracted considerable attention because the catalytic behavior can be tuned by the substituted atoms. In the present study, Sn-substituted MFI-type silicates were synthesized using a hydrothermal reaction of an amorphous S...

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Bibliographic Details
Main Authors: Kiyoshi Kanie, Moe Sakaguchi, Fumiya Muto, Mami Horie, Masafumi Nakaya, Toshiyuki Yokoi, Atsushi Muramatsu
Format: Article
Language:English
Published: Taylor & Francis Group 2018-12-01
Series:Science and Technology of Advanced Materials
Subjects:
Online Access:http://dx.doi.org/10.1080/14686996.2018.1497404
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Summary:Substitution of Al atoms in a zeolite framework by catalytic metal atoms has attracted considerable attention because the catalytic behavior can be tuned by the substituted atoms. In the present study, Sn-substituted MFI-type silicates were synthesized using a hydrothermal reaction of an amorphous Si-O-Sn precursor prepared by mechanochemical grinding of SiO2 and Sn(OH)4. The mechanochemical treatment was found to be a key technique for obtaining the amorphous Si-O-Sn precursor, where tetrahedral Sn4+ species were incorporated into the amorphous matrix. The Sn content in the framework of the MFI-type silicates was successfully controlled by the initial HCl/Si molar ratio of the hydrothermal procedures. Optical reflectance measurements revealed that the Sn4+ ions were dispersedly incorporated into the silicate framework while preserving the initial tetrahedrally coordinated species. Infrared results imply that the resulting Sn-substituted MFI-type silicate has Brønsted acid character. Precise control of the Brønsted and Lewis acid properties by Sn doping is a promising approach to the development of novel types of zeolite-based catalytic materials.
ISSN:1468-6996
1878-5514