Back to Search
Start Over
Dealumination of organic structure-directing agent (OSDA) free beta zeolite for enhancing its catalytic performance in n-hexane cracking
- Source :
- Microporous and Mesoporous Materials. 220:275-281
- Publication Year :
- 2016
- Publisher :
- Elsevier BV, 2016.
-
Abstract
- This work deals with the dealumination of organic structure-directing agent (OSDA) free beta (OFB) zeolite by different methods to change its acid amount and enhance its catalytic performance in n-hexane cracking. The OFB zeolite was pre-treated with ammonium hexafluorosilicate (AHFS) solution, steaming, or concentrated NH 4 NO 3 ( ca. 10 M) followed by calcination at high temperature. Then, thus pre-treated OFB samples can be effectively dealuminated by acid treatment with the structure retained. The H-form OFB (HOFB) and dealuminated OFB (DOFB) catalysts were characterized by using X-ray diffraction, N 2 adsorption–desorption, SEM, ICP, NH 3 -TPD, 29 Si and 27 Al MAS NMR, and pyridine adsorption FT-IR. In the catalytic cracking of n-hexane, the DOFB catalysts showed a higher propylene selectivity and a longer catalytic life than the parent Al-rich HOFB catalyst. This would be attributed to the lower amount of acid sites, especially the Lewis acid sites, which suppressed the secondary reaction of propylene and butenes and the hydride transfer to form coke.
- Subjects :
- Hydride
Inorganic chemistry
02 engineering and technology
General Chemistry
010402 general chemistry
021001 nanoscience & nanotechnology
Condensed Matter Physics
Fluid catalytic cracking
01 natural sciences
0104 chemical sciences
law.invention
Catalysis
chemistry.chemical_compound
Adsorption
chemistry
Mechanics of Materials
law
Pyridine
General Materials Science
Calcination
Lewis acids and bases
0210 nano-technology
Zeolite
Subjects
Details
- ISSN :
- 13871811
- Volume :
- 220
- Database :
- OpenAIRE
- Journal :
- Microporous and Mesoporous Materials
- Accession number :
- edsair.doi.dedup.....1a391082e1320b368a5966cf749c1dd3