Reductive dechlorination of chlorinated alkanes adsorbed on molecular sieve 13X occurs at room temperature. The dechlorination yields for alpha,omega -dichloroalkanes, such as 1,4-dichlorobutane, 1,5-dichloropentane, and 1,6-dichlorohexane, did not exceed 50%, suggesting that only one of the chlorine atoms is activated for the reductive dechlorination in the cage of the molecular sieve. Effects of an irradiation with gamma -rays on the dechlorination are described.