IR study of chlorination of alumina employing mixtures of gaseous chlorine and carbon monoxide

Abstract

The chlorination of an alumina with BET surface area of 100 m2/g has been studied in situ by transmission IR measurements at about 670 K. The chlorinating gases consisting of C1, and CO were employed individually and in equimolar proportion. The IR results do not reveal the presence of a phosgene surface species which could support the only mechanism proposed so far to explain the chlorination reaction. A detailed alternative reaction mechanism is suggested for the high tempcraturc chlorination reaction, taking into account the IR results, together with the known electron donor-acceptor properties of the activated alumina and the reaction gases: C1, molecules accept electrons from oxide ions with a lower coordination number on the alumina surface, leading to the formation of C1-and Oad. While C1-yields AlCl,, Oad reacts further with CO producing CO,.

Ligand Exchange-Mediated Activation and Stabilization of a Re-Based Olefin Metathesis Catalyst by Chlorinated Alumina

“…There is no evidence for appreciable amounts of residual H 2 O or AlCl 3 (Figure S1). 60 The presence of strong Lewis acidity, and the lack of appreciable Brønsted acidity, were verified by pyridine adsorption (Figure S2). distinguished by their characteristic chemical shift ranges (Figure S3).…”