Échange ionique dans les zéolites par la méthode sèche. Mise en évidence de l'influence de quelques paramètres

Abstract

There is only very little data on solid-state ion exchange in zeolites reported in the literature so far. These studies concern principally alkaline and alkaline earth metals. We can obtain, high exchanged zeolites with transition metals, between 30 and 50% exchange. It was shown that, both low temperature and high-temperature exchange processes occured. It was the aim of the present study to elucidate whether in principle, higher degrees of exchange can be obtained by solid-state reaction than by conventional ion exchange in salt solution, and result in catalysts more active. We also study, the influence of some parameters, such as, temperature, inert gas flow, time of exchange and the proportion of salt, on the degree of exchange. Chlorides of cobalt and iron were tested.