Separation of carrier-free Y-90 from high level waste by supported liquid membrane using KSM-17

A generator system has been developed for the preparation of carrier-free Y -90 from Sr-90 present in the high level waste (HLW) of the Purer process b y employing a supported liquid membrane (SLM) using 2-ethylhexyl-2-ethylhex yl phosphonic acid (KSM-17 equivalent to PC 88A) supported on a polytetrafl uoro ethylene (PTFE) membrane. When uranium depleted Purer HLW at appropria te acidity is passed sequentially through octyl (phenyl)-N,N-diisobutytcarb amoylmethylphosphine oxide (CMPO) sorbed on chromosorb-102 (abbreviated as CAC) and Zeolite AR1 (synthetic mordenite) columns, all the trivalent, tetr avalent and hexavalent metal ions and monovalent Cs-137 ions are sorbed. Af ter adjusting to pH 2 with NaOH the resulting effluent is used as feed in a single stage membrane cell partitioned with a PTFE membrane impregnated wi th KSM-17 and having a feed and receiver compartment with 5.0 ml capacity e ach. The receiver compartment was filled with a 0.5M HNO3 or 0.5M HCl strip ping solution. Y-90 alone is preferentially transported across the membrane leaving behind all the impurities viz. Sr-90, Sb-125, Ru-106, Rh-106, etc. in the feed compartment. This technique can yield Y-90 in mCi levels in a pure and carrier-free form for medical applications. The feed can be reused repeatedly after allowing for Y-90 buildup.