Interaction and Catalytic Decomposition of 1,1,1-Trichloroethane on High Surface Area Alumina. An Infrared Spectroscopic Study

Article abstract of DOI:10.1021/j100182a071

Transmission infrared spectroscopy has been used to study the catalytic decomposition of 1,1,1-trichloroethane, CH3CCl3, on high surface area alumina, Al2O3, in the temperature range 300 - 600 K.At 300K CH3CCl3 is reversibly adsorbed on the isolated surface hydroxyl groups of Al2O3 via hydrogen bonding.At T >/= 400 K an α,β-HCl elimination occurs, forming CH2=CCl2(g).A small amount of surface carboxylate was also formed by means of a minor reaction pathway.It was found that Lewis acid (Al3+) surface sites were involved in causing the primary reaction.This was shown by the observation that irreversible adsorption of pyridine on the Al3+ sites efficiently quenched the surface reaction.Conversely, surface Al-OH groups are not involved in the CH3CCl3 decomposition.