Morphology-Controlled Synthesis of H-type MFI Zeolites with Unique Stacked Structures through a One-Pot Solvent-Free Strategy.
ChemSusChem
; 12(16): 3871-3877, 2019 Aug 22.
Article
em En
| MEDLINE
| ID: mdl-31168958
ABSTRACT
H-type aluminosilicate zeolites are extensively used as solid-acid catalysts and support materials in industrial catalysis. However, the conventional synthesis methods involving hydrothermal syntheses and ion-exchange processes suffer from severe water pollution and toxic gas emissions. Herein, H-type MFI zeolite catalysts with a unique stacked structure were directly synthesized in the presence of NH4 F and with the help of zeolite confinement through a solvent-free route without further ion-exchange procedures. A range of exâ
situ and inâ
situ characterization procedures were used to provide evidence of the simultaneous use of pre-made ZSM-5 and NH4 F as a confined Al source and mineralizer, respectively. The confined zeolite framework of ZSM-5 prevented the formation of AlFx species between NH4 F and Al atoms, ensuring that the prepared samples had desirable acidic properties. Moreover, the resulting morphology could be controlled by using different silica substrates. The obtained H-type MFI zeolites showed excellent catalytic performance in methanol-to-gasoline reactions owing to their unique structure and directly exposed acidic sites. The developed one-pot strategy provides an alternative method for the facile synthesis of H-type zeolites with defined morphology.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article