Joseph Robert Stano
Engineers at Mexico Ave, Denver, CO

4155982, May 22, 1979

Oct 9, 1974

5/513445

Geoffrey G. Hunkin - Littleton CO
Thomas P. Fife - Lakewood CO
Joseph R. Stano - Lakewood CO

Wyoming Mineral Corporation - Denver CO

C01G 4300

423 7

Uranium ore deposits which contain certain proportions of other metals and elemental components, such as are present in redox roll front ore deposits, are selectively leached in situ by passing therethrough relatively dilute aqueous leach solutions comprising essentially from about 0. 5 to 5 grams per liter of ammonium bicarbonate and from about 0. 1 to 3 grams per liter of peroxide, preferably introduced as aqueous H. sub. 2 O. sub. 2, and sufficient ammonia to bring the solution to a pH of from about 7. 4 to 9, and preferably from 7. 5 to 8. 5, thereafter withdrawing from the ore deposit the aqueous leach solution enriched in uranium which it preferentially extracts along with a generally lower proportion of other metals and elements as compared to their respective ratios in the ore deposit, and contacting the enriched leach solution with a strong base anion exchange material to strip the uranium from the leach solution. The uranium is eluted by treating the base anion exchange material with an aqueous eluant, and finally the uranium is recovered from the uraniferous eluate by first acidifying it and then treating with ammonia to produce a precipitate of relatively pure ammonium diuranate. The stripped leach solution is separated from the base anion exchange material and the stripped leach solution is recirculated through the ore deposit after adjusting it with more ammonium bicarbonate, peroxide and ammonia.