fulltext.study @t Gmail

Isomerization of endo-dicyclopentadiene using Al-grafted MCM-41

Paper ID Volume ID Publish Year Pages File Format Full-Text
40977 45873 2012 7 PDF Available
Title
Isomerization of endo-dicyclopentadiene using Al-grafted MCM-41
Abstract

The isomerization of endo-dicyclopentadiene (endo-DCPD) using Al-grafted MCM-41 was studied as an industrial practical synthesis route for exo-DCPD. The catalyst was prepared with post-synthesis grafting method, characterized by XRD, N2 adsorption/desorption, 27Al and 29Si MAS NMR, in-situ pyridine adsorption IR and NH3-TPD. The materials retain ordered mesoporous structure and high surface area. Al atoms are preferentially anchored in tetra-coordination, but these in octa-coordination increase significantly in case of high Al content. The amount of Brønsted acid is closely related to the amount of tetra-coordinated Al species whereas that of Lewis acid corresponding to the total Al content. The prepared material shows higher activity than microporous zeolites because its mesoporous structure gives free diffusion and excellent coke tolerance capability. A good correlation between the conversion of endo-DCPD and the amount of Lewis acid was observed. Specifically, the weak Lewis acid sites catalyze the endo- to exo-isomerization, meanwhile the moderate ones account for the [2 + 2] cycloaddition of two DCDP molecules. Catalyst with Si/Al of 8 is most active due to its highest concentration of weak Lewis acid. Addition of inert solvent, relatively low reaction temperature and high catalyst dosage can improve the isomerization. The deactivated catalyst can be easily regenerated by calcination.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (147 K)Download as PowerPoint slideHighlights► Al-grafted MCM-41 shows higher activity than Hβ. ► Weak Lewis acid sites are the active site. ► Sample with Si/Al ratio of 8 shows highest selectivity of 85%, with conversion of 70%. ► The deactivated catalyst is easily regenerated by calcination.

Keywords
Dicyclopentadiene; Isomerization; Al-MCM-41; Mesoporous zeolites
First Page Preview
Isomerization of endo-dicyclopentadiene using Al-grafted MCM-41
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis A: General - Volumes 421–422, 16 April 2012, Pages 79–85
Authors
, , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us