Rene B. LaPierre, David Wu, Wilmer L. Kranich
1978
Citations
0
Influential Citations
50
Citations
Journal
Journal of Catalysis
Abstract
Abstract The catalytic hydrodechlorination of 1% solutions in xylene of 1,1-bis( p -chlorophenyl)-2,2-dichloroethylene ( p , p ′-DDE) and the corresponding ethane ( p , p ′-DDD) were studied in a continuous gas-phase reactor over a prereduced 0.35-wt% Pd on α-Al 2 O 3 catalyst at 170–230 °C, 40–670 Torr of H 2 . Reaction stoichiometry for DDE was a network characterized either by the addition of one H 2 to remove one aromatic chlorine at a time or by addition of 3H 2 , resulting in removal of two olefinic chlorines and olefin saturation. This latter process proceeds without measurable desorption of intermediates such as substituted ethylidene dichlorides, vinylchlorides, ethylchlorides, or ethylenes. Olefinic hydrocechlorination is a precursor to hydrogenation of the dechlorinated olefin. Selectivity analyses by reaction path methods established relative reaction rates for each step. The reactions were first order in hydrogen for aromatic hydrodechlorination. Rate data were fitted by Langmuir-Hinshelwood kinetics, in which xylene inhibits the surface reaction.