Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
INFLUENCE OF CRYSTALLITE SIZE ON CATALYTIC PERFORMANCE OF HZSM-5 PREPARED BY DIFFERENT METHODS IN 2,7-DIMETHYLNAPHTHALENE ISOMERIZATION
Autore:
PU SB; INUI T;
Indirizzi:
KYOTO UNIV,GRAD SCH ENGN,DEPT ENERGY & HYDROCARBON CHEM,SAKYO KU KYOTO 60601 JAPAN KYOTO UNIV,GRAD SCH ENGN,DEPT ENERGY & HYDROCARBON CHEM,SAKYO KU KYOTO 60601 JAPAN
Titolo Testata:
Zeolites
fascicolo: 4, volume: 17, anno: 1996,
pagine: 334 - 339
SICI:
0144-2449(1996)17:4<334:IOCSOC>2.0.ZU;2-H
Fonte:
ISI
Lingua:
ENG
Soggetto:
HIGHLY SELECTIVE SYNTHESIS; ZSM-5 TYPE ZEOLITES; LIGHT OLEFINS; METHANOL; H-ZSM-5; BETA;
Keywords:
HZSM-5; RAPID CRYSTALLIZATION METHOD; CRYSTALLITE SIZE; EXTERNAL SURFACE; ISOMERIZATION OF 2,7-DIMETHYLNAPHTHALENE TO 2,6-DIMETHYLNAPHTHALENE; ACID SITE DISTRIBUTION; PRODUCT SELECTIVITY;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
28
Recensione:
Indirizzi per estratti:
Citazione:
S.B. Pu e T. Inui, "INFLUENCE OF CRYSTALLITE SIZE ON CATALYTIC PERFORMANCE OF HZSM-5 PREPARED BY DIFFERENT METHODS IN 2,7-DIMETHYLNAPHTHALENE ISOMERIZATION", Zeolites, 17(4), 1996, pp. 334-339

Abstract

HZSM-5 samples synthesized by rapid crystallization method possessed smaller crystallite sizes, and Al distributions in the crystallite were more uniform than in sample prepared by the conventional method. In 2,7-dimethylnaphthaIene (2,7-DMN) conversion, a high isomerization activity and nearly 70% selectivity to 2,6-DMN were obtained on an HZSM-5having a small and uniform crystallite size. On the other hand, both the activity and shape selectivity on large crystallites were low. This is because small crystallites have a larger external surface, which offers a higher number of pore entrances and enhances the reaction occurring inside the pore channels compared with large crystallites. Furthermore, it is found that the selectivity to 2,6-DMN should be 100% ifthere is no acid site on the external surface; in other words, the shape-selective isomerization oi 2,7-DMN to 2,6-DMN on ZSM-5 Is based onthe product selectivity inside the pore channels, From this evidence,it is concluded that in 2,7-DMN isomerization to 2,6-DMN, the reaction activity is related to the crystallite size, whereas the shape selectivity is determined by the ratio of surface acid sites to total acid sites; in other words, uniformity of Al distribution, Therefore, a reduction in crystallite size and decrease In acid sites on the external surface are significant ways to improve catalytic activity and shape selectivity, respectively.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 12/07/20 alle ore 06:29:11