Cellulose triacetate (1.25 g/100 mL CH2Cl2), 2 mL, mixed with o-nitrophenyloctyl ether (10% in CH,Cl,) and with 0.1 M di(2,4,4-trimethylpentyl)dithiophosphinic acid (Cyanex 301) as ionic carrier, was poured on glass to evaporate CH2Cl2 in 12 h and to soak the membrane in H2O 12 h, to yield a PIM, 20-mum thick. Trioctylamine, dibenzo-18-crown-6 and dicyclohexane-21-crown-7 ethers, and 5,8-dinonylnaphthalenesulfonic acid were also used as ionic carriers. Com. galvanic wastes, Cr(VI) 2860, Zn(II) 1830, Cd(II) 0.11, Fe (III) 4.6 mg/L, pH 1.03, lost in 75 h 69, 99, 66 and 52% of the resp. metals. Cs-137, Sr-90, and Co-60 were collected from aq. 0.1 M NaNO3, pH 4.3, in 98, 95 and 95%, resp. The Cyanex 301 membrane enabled 98% of Co(II) to be separated and, as a next step, the crown ether membrane enabled 95% of Cs(I) to be separated. Ionic carriers were found to control membrane efficiency.