%i 27Al and 'H magic-angle-spinning NMR and relaxation measurements on thermally treated zeolite Na,$a, ,,-A have been carried out in order to study framework defects responsible for, and surface barriers to, molecular diffusion. Various possible mechanisms for the formation of such defects are cons
Extra-framework aluminium in thermally treated zeolite CaA
โ Scribed by D. Freude; J. Haase; H. Pfeifer; D. Prager; G. Scheler
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- English
- Weight
- 360 KB
- Volume
- 114
- Category
- Article
- ISSN
- 0009-2614
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โฆ Synopsis
Nuclear magnetic resonance spectra of aluminium mcludtig magic-angle spinning (27Al MAS NMR) have been m-red in order to study the dealumination which 1s caused by a heat treatment of zeolite CaA. The extra-lattice alummium edits partly in the form of Al(OH), anions, corresponding to at most about 17% of lattice dealuroination.
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