In situ study of dehydration of ECR1: Na-as synthesized and NH4-exchanged in comparison

The thermal behavior of Na-as synthesized and NH4 exchanged samples of ECR-1 has been studied by synchrotron radiation powder diffraction. The temperature resolved experiments were performed in capillary using a translating imaging plate system. The aim of this study is to follow in situ the dehydration mechanism of the zeolite ECR1, in its as-synthesized and NH4-exchanged form in order to determine its thermal stability and whether the structure undergoes phase transition during dehydration. The as-synthesized sample is stable up to 715°C, whereas the NH4-exchanged one is stable up to 925°C. Cell parameter refinements show a total volume decrease of 0.95% for the as-synthesized phase and of 3.82% for the NH4 form. © 2008 Elsevier B.V. All rights reserved.