Uranium is recovered from refractory carbonaceous sulfide ores or concentrates by leaching with nitric acid, followed by sorption on an ion exchange resin. In addition, the nitric acid leach solution is regenerated and recycled. Thus, 94 pct of the u in an ore containing u 0.50, Organic carbon 8.91, and s 6.3 pct was leached with 3.0M hno3 at 120 deg c. The pregnant solution contained 0.0057M u, 0.20M fe, 0.33M so42-, 0.005M no3-, and had a ph of 0.90. The leach solution was fed to a column of -20 mesh +50 mesh strong base anion exchange resin at a flow rate of 0.75 to 1.0 Gal/(min- ft3) until the effluent solution from the column contained the same u concentration as the influent solution. The resin loaded to 2.8 Lb u/ft3 of resin, which is representative of commercial loadings. Elution was accomplished with 1m nacl acidified to ph 1.14 With h2so4. Over 96 pct of the u was stripped from the resin with 10 bed volumes of eluant. The strip solution was neutralized to ph 7.0 With nh4oh and filtered. The "yellow cake" product contained 56.2 pct u.
U.S. Pat. 4,098,866, July 4, 1978, Chem. Abstr. Not Found