75-09-2 Catalytic dechlorination of carbon tetrachloride in liquid phase with methanol as H-donor over AG/C catalyst

Catalytic hydrodechlorination of carbon tetrachloride (CCl₄) is an effective measure to remove CCl₄due to its pollutant character. The dechlorination of CCl₄to dichloromethane (CH₂Cl₂) and chloroform (CHCl₃) with a molar ratio of 3:2 was catalyzed by carbon-supported silver (Ag/C) catalyst in methanol solution. It was proposed from the catalytic results and characterization (X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy) data that, the chloride ion is abstracted from adsorbed CCl₄by Ag to form CCl₃and CCl₂radicals and silver chloride (AgCl), and meanwhile the dehydrogenation of methanol over Ag domains intrigues initial active Ag-H species and formaldehyde (HCHO): then the CCl₃and CCl₂radicals are combined with Ag-H to generate reaction products (CHCl₃, and CH₂Cl₂) and Ag, and the dehydrogenated product HCHO facilitates the regeneration of formed AgCl to Ag with formation of carbon monoxide and hydrogen chloride. The catalyst can be recovered and recycled, and there was no significant decrease in catalytic activity and selectivity after 4^threcycling. Copyright https://www.lookchem.com/CASDataBase_75-09-2.htm