Catalytic Decomposition of Chlorofluorocarbons in the Presence of Alcohols. -Screening of Catalysts and Effect of Alcohol-

Abstract

The catalytic decomposition of CFC-112 and CFC-113 (CFCs) in the presence of ethanol over iron (III)chloride supported on active charcoal was carried out under various reaction conditions. The carbon atoms of the CFCs ended up as CO and CO₂, the chlorine atoms as ethyl chloride and the fluorine atoms as hydrogen fluoride.
The catalytic activity of various metal halides supported on active charcoal was investigated for the decompo sition of CFC-113 at 210°C. It was found that the catalytic activity of several metal halide was superior to that of iron (III) chloride.
The catalytic d ecomposition of CFC-113 in the presence of various alcohols (or ethers) was performed over iron (III) fluoride supported on active charcoal in order to investigate the effect of molecular structure of alcohol on the destruction of CFC's. The higher homologues of n-alkyl alcohol increased the conversion of CFC-113. It is reasonable to consider that the nucleophilic reactivity of the alcohols might be increased by the inductive effect of larger alkyl groups. However, ethers with larger alkyl groups showed a smaller reactivity, because of steric hindrance of the bulky alkyl groups.
While the catalytic activity of iron (III) halides supported on active charcoal dec reased during the decomposition of CFC-113, the durability of catalytic activity was greatly improved by the addition of copper (II) chloride.