Performance of Methanol-to-Olefins Catalytic Reactions by the Addition of PEG in the Synthesis of SAPO-34

SAPO-34, a silicoaluminophosphate zeolite, has been synthesized by the hydrothermal method with the addition of different molecular weights of polyethylene glycol (PEG), and has been characterized with XRD, SEM, N2 adsorption-desorption, FT-IR, and NH3 temperatureprogrammed desorption (NH3-TPD). We...

Full description

Saved in:
Bibliographic Details
Published in:Transactions of Tianjin University 2017-11, Vol.23 (6), p.501-510
Main Authors: Wang, Yaquan, Wang, Zhao, Sun, Chao, Chen, Hengbao, Li, Hongyao, Li, Haoyang
Format: Article
Language:English
Subjects:
Alkenes
Catalysis
Catalysts
Chains
Chemical synthesis
Crystallization
Desorption
Engineering
glycol
Chain
Humanities and Social Sciences
length
Particle
Mechanical Engineering
Methanol
Methanol-to-olefins
Morphology
multidisciplinary
Particle size
Polyethylene
Polyethylene glycol
Research Article
SAPO-34
Science
Selectivity
size
Nanoplate
Stability
Thickness
Zeolites
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:SAPO-34, a silicoaluminophosphate zeolite, has been synthesized by the hydrothermal method with the addition of different molecular weights of polyethylene glycol (PEG), and has been characterized with XRD, SEM, N2 adsorption-desorption, FT-IR, and NH3 temperatureprogrammed desorption (NH3-TPD). We studied SAPO-34 as a catalyst in the methanol-to-olefins (MTO) reaction, in a fixed-bed reactor. The results show that the chain length of PEG has a great influence on the particle size and morphology of SAPO-34. PEG acts as inhibitor in the crystallization process. With the increase of the chain length of PEG used in the synthesis, from a relative molecular weight of 400-6000, the morphology of SAPO- 34 changes gradually from cubic to nanoplate-like and then changes to cubic again. The particle size decreases markedly at first and then increases to some extent. The catalytic stability in the MTO reaction also increases first and then decreases, with all the catalysts having almost the same selectivity to olefins. When the sample is synthesized with PEG800, the particles become nanoplate-like with a thickness of 46 nm on average, and the catalytic stability is appreciably prolonged, which is attributed to the shorter diffusion paths of the reactants in the zeolite.
ISSN:1006-4982
1995-8196
DOI:10.1007/s12209-017-0065-y