The transport of cadmium ions from hydrochloric acid solutions across a bulk liquid membrane by using dicyclohexyl-18-crown-6 (DC18C6) dissolved in dichloromethane has been studied at 25 degrees C. The effect of the fundamental parameters influencing the transport, e.g., hydrochloric acid concentration in the feed phase, DC18C6 concentration and the type of diluent used in the membrane and time of transport have been investigated. The transported amount of the cadmium ions (initial concentration 0.00 1 M) from a 6 M hydrochloric acid solution across a dichloromethane solution of DC18C6 (0.05 M) into distilled water (receiving phase) was found to be 98.3 (+/- 1.8) percent after 6 h. The selectivity and efficiency of the method toward cadmium ions were tested by performing the competitive transport experiments on the mixtures containing Cd2+, Ni2+, Mn2+, Co2+, Zn2+, Pb2+, and Fe2+ ions. The best selectivity was found for the recovery of the cadmium ions from its mixture with Ni2+, Mn2+, Co2+, and Ph2+ ions. Thus, the method can be proposed for the application in cadmium recovery from the sources containing these ions such as spent rechargeable nickel-cadmium batteries.