ALUMINUM ZONING IN ZSM-5 AS REVEALED BY SELECTIVE SILICA REMOVAL
被引:171
作者:
DESSAU, RM
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机构:Mobil Research and Development Corporation, Central Research Laboratory, Princeton, NJ
DESSAU, RM
VALYOCSIK, EW
论文数: 0引用数: 0
h-index: 0
机构:Mobil Research and Development Corporation, Central Research Laboratory, Princeton, NJ
VALYOCSIK, EW
GOEKE, NH
论文数: 0引用数: 0
h-index: 0
机构:Mobil Research and Development Corporation, Central Research Laboratory, Princeton, NJ
GOEKE, NH
机构:
[1] Mobil Research and Development Corporation, Central Research Laboratory, Princeton, NJ
来源:
ZEOLITES
|
1992年
/
12卷
/
07期
关键词:
ZSM-5;
ALUMINUM;
ZONING;
SILICA REMOVAL;
D O I:
10.1016/0144-2449(92)90049-U
中图分类号:
O64 [物理化学(理论化学)、化学物理学];
学科分类号:
070304 ;
081704 ;
摘要:
Treatment of ZSM-5 crystals with an aqueous base results in partial dissolution of the sample with preferential removal of silica. The treated zeolites, which now have lower silica/alumina ratios, exhibit higher exchange capacities and enhanced catalytic activities. Scanning electron micrographs of base-treated large-crystal ZSM-5 samples revealed that highly selective dissolution of the interior of the crystals had occurred, while leaving the exterior surface relatively intact. These results provide dramatic evidence for aluminum zoning in large-crystal ZSM-5 synthesized in the presence of quaternary directing agents.