× 20 cm length) was fused from the base of the cell. The height of the tube inside the cell was 4.0 cm from the basal plane. The whole assembly was kept in a thermostat maintained at 30 °C. The transport experiments were performed with 50.0 mL of 7.14 ´ 10-5 mol L-1 Ce(IV) solution at pH 9.0 as source phase and 50.0 mL of 0.1 mol L-1 HCl as receiving phase. The liquid membrane consisted of 75 mL of 7.14 ´ 10-5 mol L-1 C4RAHA in ethyl acetate. A synchronous motor (200 rpm) provided constant reproducible stirring from the top. The amount of Ce(IV) transported from the source phase to the receiving phase was measured by ICP OES. The transport data