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Temperature programmed desorption studies on the penetration of ammonia into the sodalite cages of A, X and Y type zeolites

✍ Scribed by V. Kanazirev; N. Borisova

Publisher: Elsevier Science
Year: 1982
Tongue: English
Weight: 599 KB
Volume: 2
Category: Article
ISSN: 0144-2449
DOI: 10.1016/s0144-2449(82)80036-5

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✦ Synopsis

The adsorption of ammonia on sodium forms of A, X and Y type synthetic zeolites and mordenite are examined in the 423-573 K temperature interval in a flow apparatus using helium as carrier gas. Diffusion controlled penetration of ammonia into the sodalite cage, most marked for Y type zeolites, is found to take place by temperature programmed desorption up to 823 K. It is shown that the accessibility of the sodalite cages of faujasite type zeolites to ammonia strongly diminishes on increasing the Si/AI ratio. The assumption is made that this effect is due to small structural changes undergone by the zeolite. It is not excluded that these changes could also affect the Na + location.

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📂 Article 📅 1995 🏛 Elsevier Science 🌐 English ⚖ 379 KB