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Titolo:
High-silica molecular sieve syntheses using the sparteine related compounds as structure-directing agents
Autore:
Tsuji, K; Wagner, P; Davis, ME;
Indirizzi:
CALTECH, Div Chem & Chem Engn, Pasadena, CA 91125 USA CALTECH Pasadena CAUSA 91125 iv Chem & Chem Engn, Pasadena, CA 91125 USA
Titolo Testata:
MICROPOROUS AND MESOPOROUS MATERIALS
fascicolo: 3, volume: 28, anno: 1999,
pagine: 461 - 469
SICI:
1387-1811(199905)28:3<461:HMSSUT>2.0.ZU;2-O
Fonte:
ISI
Lingua:
ENG
Soggetto:
EXTRA-LARGE-PORE; PURE-SILICA; DERIVATIVES; ZEOLITE; CRYSTAL; CIT-5; SALTS;
Keywords:
CIT-5; high-silica molecular sieves; organic-inorganic composites; sparteine derivatives; synthesis;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
18
Recensione:
Indirizzi per estratti:
Indirizzo: Davis, ME CALTECH, Div Chem & Chem Engn, Pasadena, CA 91125 USA CALTECH Pasadena CA USA 91125 Chem Engn, Pasadena, CA 91125 USA
Citazione:
K. Tsuji et al., "High-silica molecular sieve syntheses using the sparteine related compounds as structure-directing agents", MICROP M M, 28(3), 1999, pp. 461-469

Abstract

Three quaternary ammonium compounds are synthesized from sparteine and their performances in high-silica molecular sieve syntheses investigated. N(1)-Methyl-alpha-isosparteinium (compound A) is found to form the pure-silica molecular sieve with the CFI topology that was first synthesized with its diastereomer N(16)-methylsparteinium (B). The crystallization time for the synthesis of pure-silica CFI using A as an organic agent is shorter than that with B. The crystal size of the product obtained with A is much smaller than that recovered when using B. These results indicate that A is a better structure-directing agent for the formation of the CFI than B. Molecular modeling studies suggest that the reason A is a better structure-directing agent for CFI than B is that A can form a greater number of Van der Waals interactions with the silica framework of CFI. The very rigid and bulky compound, N(1),N'(16)-endomethylenesparteinium (compound C) does not yield any crystalline molecular sieves over a range of the reaction conditions. The lack of success with C could be due to its decreased hydrophobicity and hydrothermal stability compared to A and B. (C) 1999 Elsevier Science B.V. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 25/01/20 alle ore 16:08:25