Pore Structure of USY Zeolites in Dependence on Steaming Condition
Научная публикация
| Общее |
Язык:
Английский,
Жанр:
Статья (Full article),
Статус опубликования:
Опубликована,
Оригинальность:
Оригинальная
|
| Журнал |
Zeitschrift fur Anorganische und Allgemeine Chemie
ISSN: 0044-2313
, E-ISSN: 1521-3749
|
| Вых. Данные |
Год: 2014,
Том: 640,
Номер: 3-4,
Страницы: 577-581
Страниц
: 5
DOI:
10.1002/zaac.201300403
|
| Ключевые слова |
Dealumination, Pore analyses, Structure, Zeolites |
| Авторы |
Lutz Wolfgang
1
,
Shutilov Roman A.
2
,
Gavrilov Vladimir Yu.
2
|
| Организации |
| 1 |
Brandenburgische Technische Universität Cottbus, Volmerstr. 13, 12489 Berlin, Germany
|
| 2 |
Boreskov Institute of Catalysis, Novosibirsk, Russia
|
|
Thermo-chemical dealumination of zeolite Y is accompanied by formation of different mesopore types. Closed mesopores in the nuclei and open pores at the crystal surface occur due to decomposition of its corresponding frameworks which are unstable in steam. Third type of lattice mesopores is formed inside the microporous bulk after removal of aluminum atoms if the remaining hydroxyl nests dehydroxylate. This process leads to a rearrangement of the zeolite framework. In contrast to the observed phenomenon, the defects are healed by migrating of ortho-silicic acid (H4SiO4) from the surface to the hydroxyl nests under conditions of suitable steaming. Since mesopores in USY zeolites (ultra stable Y) reduce their catalytic activity and the sorption capacity, they could be minimized by a proper treatment.