Application of inorganic membranes was considered for radioactive wastes processing purpose. The results of experiments with ceramic membranes in nanofiltration and ultrafiltration range are presented in the paper. The experiments were performed with non-active and radioactive model solutions and original radioactive waste samples. To achieve high decontamination factors the process was arranged as a "seeded ultrafiltration", e.g. UF process enhanced by chemical complexation. Such complexing agents as poly(acrylic) acid and poly(acrylic) acid salts of different crosslinking, polyethylenimine and cyano-ferrates of transient metals were tested. It was proved that decontamination factors for hybrid process were higher than those for membrane filtration solely. The effectiveness of complexation by each ligand was strongly pH-dependent. (C) 2003 Elsevier B.V. All rights reserved.