Recovery of uranium by direct low acid leaching from copper concentrator tailing

It is already established that copper ores of Singhbhum Thrust Belt contain on an average 0.01% U3O8. Uranium is being recovered from the tailings of Rakha, Surda and Mosaboni copper concentrators of HCL by tabling method but the recovery is low. Since the proven resources in the country are limited therefore to meet the uranium requirement it has to be obtained from all the available sources of uranium and has to be recovered to the maximum possible extent. The recovery of uranium by direct leaching method from the copper concentrator tailings in the Singhbhum thrust belt will be a step in this direction. This paper deals with the leaching characteristics of above mentioned copper concentrator tailings. The leaching efficiencies were determined both under low acid condition i.e. at pH 2 to 2.2 and also under standard conditions fixed for leaching of Jaduguda ore on laboratory scale. The leaching efficiency was found to be more or less the same but under Jaduguda ore leaching conditions the reagent consumptions were high. Therefore it was decided to conduct large scale tests under low acid conditions and the tests were conducted at 200 kg scale. Suitable leaching conditions were temperature 40-45degC, pH 2 to 2.2, emf -500 mV and leaching time 8 hrs. Under these conditions U3O8 leaching efficiencies were 80-82% from Rakha copper tailings, 88-90% from Surda copper tailings and 78-80% from Mosaboni copper tailings. (author). 4 tabs