Propriétés des alumines chlorées

Nature and Estimation of Functional Groups on Solid Surfaces

“…The S02 content became negligible only after evacuation at K, and the quantity of chloride on the surface corresponded to that of active hydrogen on the original surface [445,495]. The surface of alumina has been chlorinated with CCl 4 vapor at 475 K [723]. The reaction runs very similarly with titania [714].…”

“…On treatment of Ti0 2 (anatase) with anhydrous HCl at 298 K, a quantity of chloride was found on the surface after evacuation that corresponded to the original OH content [445]. It was shown by infrared spectroscopy that the OH groups were not all replaced by Cl; the water produced is retained on the surface, and species like Ti 4 +(H 2 0) Cl-and H 3 0+Cl-were observed [722,723]. On outgassing, HCl is evolved, and the chloride content approaches half the original hydroxyl content at 513 K [445].…”