ISSN:
1573-1111
Keywords:
Zeolite inclusion complexes
;
nitrate complexes
;
IR spectra
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The changes occurring in the included component in the course of thermal treatment of inclusion complexes of zeolite 4A with alkali nitrates were followed by IR spectroscopy and the results obtained were correlated with the data of TG analysis. An increase in temperature caused changes in the breadth and intensity of the nitrate bands (at about 1450 and 1380 cm−1) and the appearance of a new band at about 1350 cm−1. All the mentioned effects relate to the temperature interval starting from room temperature up to 670 K and are attributed to the increase in the thermal motion of included species in zeolite cages. The activation energy of the coordination change of the nitrate groups in the cage was calculated from the ratio of intensities of the nitrate bands at 1450 and 1350 cm−1 and the intensity of the zeolite band at 460 cm−1, originating from aT−O bending vibration as a function of temperature. At temperatures exceeding 720 K decomposition of included nitrate was noticed. Having this in mind, it was concluded that the changes of the band intensities were closely connected with this process.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00662083
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