CATALYTIC DECOMPOSITION OF ALIPHATIC HALIDE

PROBLEM TO BE SOLVED: To provide a method for the catalytic decomposition of aliphatic halides, not producing secondary pollutants, such as lower monohaloalkyls and/or monochlorotrifluoromethane (CFC-13) as by-products, and capable of maintaining high activity of the catalytic system for a long period. SOLUTION: This method for the catalytic decomposition of aliphatic halides comprises using (i) a two-component catalyst system of metal halide catalyst, composed of ferric fluoride and/or ferric chloride as the major catalyst, and cupric fluoride and/or cupric chloride as the cocatalyst and conducting (ii) the decomposition of the aliphatic halides characterized by the following 3 steps; (1) the decomposition is conducted through a multi-stage reaction tower where at least 2 reaction towers packed with the catalyst are arranged in series; (2) a cracked gas produced by the decomposition of the aliphatic halides are contacted with an aqueous alkaline solution in an alkaline scrubber arranged midway of the multi-stage reaction tower; and (3), after the contact of the gas with the alkaline solution, part of the gas is returned to the previous stage of the reaction tower, and the remainder is supplied to the next stage of the reaction tower.