In order to reduce the overall management cost and improve the long-term safety of disposal, separation of the liquid radioactive waste into different streams for separate conditioning and disposal has been studied using a combination of chemical precipitation and physical separation. In this paper the potential of some novel additives to enhance decontamination level from the following waste streams are reported: Low (LLW) and Medium Level Liquid Waste (MLLW) at Harwell (UK); Low Level Liquid Waste (LLLW) from PWR Tihange nuclear plant in Belgium; First cycle aqueous raffinate (1AW) from MTR fuel reprocessing plant (Italy). Combination of precipitation and ultrafiltration or centrifugation seems promising for improving both decontamination and volume reduction factors for treatment of various radioactive waste. Finally the efficiency of ultrafiltration as a decontamination tool has been assessed on each of radioactive streams in a cooperative programme involving each participating author.