Catalytic chemistry of chloro- and chlorofluorocarbon dehalogenation: from macroscopic observations to molecular level understanding

The macroscopic performance of monometallic Group VIII metal catalysts and bimetallic Group VIII metal-containing catalysts for dehalogenation reactions and the mechanistic aspects of the reactions are reviewed. Of primary importance is the dechlorination of multiply chlorinated C-2-C-3 hydrocarbons containing Cl atoms attached to adjacent carbons. The chemistry of geminal chloro- and chlorofluorocarbons (CFCs) dehalogenation catalyzed by supported noble metal-containing catalysts in the presence of H-2 is also reviewed. The hydrodehalogenative oligomerization of C, chloro and chlorofluorocarbons is considered with the greatest detailed; however, the hydrodechlorination chemistry is also addressed. (C) 2004 Elsevier B.V. All rights reserved.