Recovery Of Uranium Metal By Selective Chemical Leaching Of Copper U Clusters And Thereby Recovering Uranium From Leach Solutions By Solvent Extraction Technique Using TBP-HNO_3

摘要

Uranium Metal ingots are processed at fuel fabrication facilities and converted into fuel clusters for the use in nuclear Research reactors. As an intermediate stage U-Cu pins are produced by extrusion techniques at high pressure and temperature. Further these pins are cut into proper size and made into U-Aluminium clusters. Copper Uranium clusters contain about 3-4% copper on uranium basis. As waste generated is in tonne quantities it was thought worthwhile to recover U from this waste. Process followed for recovery of uranium form the entire material is done by solvent extraction route. As has been observed that it is very difficult to remove copper from uranium metal by physical methods. Physical separation of copper from Uranium metal was difficult. Uranium Extraction Division (UED) has developed a process where entire copper is selectively leached and there remain only U metal rods, which contain < 25 ppm Cu on surface. This metal rod is nuclear grade pure and without incurring much cost it is melted & recycled at fuel fabrication facilities. Process developed at UED reduces the cost of incarnation and chemical costs in solvent extraction process for purification of uranium. During leaching of copper uranium also gets dissolved along with copper. Uranium from the solution is recovered by solvent extraction route using TBP-HNO_3 system. By following this process more than 99.9% U is recovered. Cupric nitrate solution containing 32 gpl Cu is disposed as solid waste by precipitating as cupric hydroxide.