Open this publication in new window or tab >>2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]
Zeolites are a type of microporous crystalline materials that have been widely used in industrial applications including separation, adsorption, and catalysis. However, great limitations on diffusion through these materials can arise due to the small pores present in mircoporous frameworks, and this can impact catalytic reactions in particular. The synthesis of hierarchical zeolites has solved the diffusion problem. In this thesis, various hierarchically porous materials have been synthesized and tested as catalysts.
In the first part of this thesis, a titanium-containing hierarchically porous silicate material has been constructed from double-four-ring (D4R) units as building blocks.
In the second part of this thesis, hierarchical MWW zeolites were synthesized by swelling and pillaring of a lamellar MWW zeolitic precursor (MCM-22) using D4R building units. The synthesis procedure has been carefully studied by various characterization methods, such as PXRD, TEM, N2 adsorption–desorption etc.
In the last part of this thesis, MFI zeolites with controllable hierarchical pore systems have been prepared. Firstly, hierarchical ZSM-5 and TS-1 with open pores were generated using a temperature programmed dissolution–recrystallization post-synthesis treatment and tested as catalysts for benzyl alcohol self-etherification and cyclohexanone ammoximation. Secondly, single-crystalline hierarchical shell-like ZSM-5 has been synthesized via a dissolution–recrystallization post-treatment of mesoporous ZSM-5. The post-treatment increased the catalytic activity of the ZSM-5 zeolite for the aldol condensation of bulky substrates.
Place, publisher, year, edition, pages
Stockholm: Department of Materials and Environmental Chemistry, Stockholm University, 2018. p. 96
Keywords
Zeolites, Porous material, Hierarchical, Synthesis, Catalysis, MFI zeolite, MWW zeolite, ZSM-5, TS-1
National Category
Chemical Sciences
Research subject
Inorganic Chemistry
Identifiers
urn:nbn:se:su:diva-159912 (URN)978-91-7797-444-4 (ISBN)978-91-7797-445-1 (ISBN)
Public defence
2018-10-24, Magnélisalen, Kemiska övningslaboratoriet Svante Arrhenius väg 16 B, Stockholm, 10:00 (English)
Opponent
Supervisors
Funder
Swedish Research Council
Note
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 2: Manuscript. Paper 4. Accepted.
2018-10-012018-09-102022-02-26Bibliographically approved