Stability of Ti in MFI and Beta structures: a comparative study

被引：98

作者：

Carati, A ^{[1
]}

Flego, C ^{[1
]}

Massara, EP ^{[1
]}

Millini, R ^{[1
]}

Carluccio, L ^{[1
]}

Parker, WO ^{[1
]}

Bellussi, G ^{[1
]}

机构：

[1] EniTecnol, I-20097 San Donato Milanese, Italy

来源：

MICROPOROUS AND MESOPOROUS MATERIALS | 1999年 / 30卷 / 01期

关键词：

FT-IR; H(2)O(2); (29)Si MAS NMR; Ti-beta; TS-1; UV-vis; XRD;

D O I：

10.1016/S1387-1811(99)00018-9

中图分类号：

O69 [应用化学];

学科分类号：

081704 ;

摘要：

The structural stabilities of TS-1 (Ti-MFI) and Ti-Beta zeolites after exposure to aqueous H(2)O(2) (30% w/w) have been examined by X-ray diffraction and spectroscopic methods (W-vis, IR and (29)Si MAS NMR). The catalytic properties of these molecular sieves are dependent on the stability of Ti(IV) in the framework. TS-1 was confirmed to be stable towards H(2)O(2) solution, in agreement with its well-known catalytic applications (e.g. hydroxylation, epoxidation, ammoximation). Ti-Beta is not stable. Physical studies confirm the partial hydrolysis of titanium during H(2)O(2) treatments with formation of highly defective situations and Ti movement to extraframework positions during the following calcination. Hence, dramatically different catalytic behaviors and lifetimes are expected for these two catalysts. (C) 1999 Elsevier Science B.V. All rights reserved.

引用

页码：137 / 144

页数：8

共 21 条

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[Anonymous], 1990, CHIM IND MILAN

[2]

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