AMMONIA INTERACTION AND REACTION WITH AL-PILLARED MONTMORILLONITE - AN IR STUDY

Interaction of ammonia (both as NH3 and ND3) with plain and Al-13-pill ared montmorillonite has been studied by means of IR spectroscopy. Up to seven types of hydroxyls have been identified on the basis of their behaviour, for which a tentative nature and location are proposed. Al -13-pillars behave to some extent as alumina particles, showing e.g. b asic hydroxyls. Pillars and day sheets show synergetic effects, concer ning both the acidity and the reactivity of the PILC. On the one hand, new acidic hydroxyls are formed, some of which undergo proton transfe r to ammonia. On the other hand, Si-O-Al bridges at the border region between the clay sheet and the pillar are cleaved by NH3, with formati on of non-acidic AlNH2, species. (C) 1998 Elsevier Science B.V.