Hollow fiber supported liquid membrane: a novel technique for separation and recovery of plutonium from aqueous acidic wastes

Low plutonium content acidic waste is generated in nuclear chemical facilities. Study was initiated to develop hollow fiber supported liquid membrane (HFSLM) technique for quantitative separation and recovery of plutonium (Pu) from such wastes using tri-n-butyle phosphate (TBP) in dodecane as carrier. Hollow fiber test module was fabricated using 20 lumens of 33.91 cm2 surface area and 9 cm length. After satisfactory testing of the hydrodynamic condition of the module, it was operated at a flow rate of 3 ml min−1 on recycling mode with acidic waste solution containing Pu=8 mg dm−3, uranium=15 dm−3, gross β−=49.33 mCi dm−3, gross γ=15.73 mCi dm−3 and acidity 3 M HNO3. In presence of various fission products, selective permeation of Pu(IV) through the bundle of hollow fiber test module was observed to be more than 90% into a stripping phase consisting 0.1 M NH2OH·HCl in 0.3 M HNO3. A model is presented to describe the transport mechanism and to evaluate the mass transfer coefficient. The radiation stability was also tested by exposing the membrane upto irradiation level of 1 M rad. Potentiality of the method for the selective separation of plutonium from acidic waste is, thus, clearly seen.