DRFT-IR Studies of the Surface of γ-Alumina
Citations Over TimeTop 10% of 1997 papers
Abstract
γ-Alumina surfaces dehydrated at 450 and 700 °C were studied by using the conventional pyridine adsorption-DRFTIR technique. Three types of Lewis acid sites are present on the surface, and in each case pyridine adsorbed on them is concomitantly interacting with their adjacent OH groups. Because only three types of Lewis acid sites are present, only three hydrogen bonding bands were observed upon pyridine adsorption. From correlation of OH bands with hydrogen bonding bands, it is found that weak Lewis acid sites have type II66 or II64 OH groups as their neighbors, medium strong Lewis acid sites have type III OH groups near by, and strong Lewis acid sites have type I6 OH groups next to them. Dehydration at 700 °C generates more types of OH groups that also interact with pyridine. The reactivity of OH groups is not determined by their acidity and space restrictions, but rather by their proximity to Lewis acid sites. We assigned the three types of Lewis acid sites to five-, four-, and three-coordinate Al3+ ions.
Related Papers
- → Reactivity of highly Lewis acidic diborane(4) towards pyridine and isocyanide: formation of boraalkene–pyridine complex and ortho-functionalized pyridine derivatives(2017)49 cited
- → Rhodium(I) Complexes as Useful Tools for the Activation of Fluoroolefins(2020)15 cited
- → Water soluble σ-bonded organochromium compounds; unsubstit utedand substituted dichlorotris(pyridine)benzylchromium(III) complexes(1966)17 cited
- [Adsorption properties of dye compounds on the sediments in Qinghe].(2002)
- → Preparation of corn stalk adsorbent and its adsorption performance for Pb2+ in aqueous solution(2022)