THE EXTRACTION OF RADIUM FROM URANIUM ORE CONCENTRATES USING LEAD AS THE CARRIER

The possibility for extracting radium from uranium ore concentrates using lead as the carrier has been studied. A process is being developed and demonstrated on a laboratory scale. Uranium ore concentrates are attacked with 40% nitric acid. Pb (Ra) SO4 is precipi- tated by adding lead and sulfuric acid, which is then dissolved in a 120 g/1 solution of EDTA having pH 9.7. The acidity of this solution is adjusted to a pH of 4, and radium is coprecipitated from the solution with barium sulfate. The later is completely dissolved in a 80 g/1 solution of EDTA having pH8.5. The solution is acidified and used as the starting solution for ion-exchange separation.The influence of the NH4+ Concentration on the separation of radium from barium has been investigated. With this in mind, the optimum condition for the separation can be chosen. The pure solution of radium is obtained by only two successive ion-exchange chromatographic separation steps. The radium concentration in the portion of the eluate containing radium is 210-245 mg/1, but that of barium is 0.12-0.22 mg/1. The overall yield of radium is higher than 84%. EDTA and Pb(NO3)2 can be regenerated and retur-' ned to the process. => ' : '