process for recovering valuable amount of refractory metals

摘要

1359245 Recovering metal values CONTINENTAL ORE CORP 23 May 1972 [18 June 1971] 24318/72 Heading C1A V, Mo, W, Ti and Nb metal values are recovered from their concentrates by forming an aq. soln. of the metal, 80% of which is in the highest oxidation state, adding to the soln. FeSO 4 or FeCl 3 in an amount to provide an Fe/metal mass ratio of 0À1-1À0, precipitating a metal/Fe/ammine complex at a pH of 2À5-4À0 in the presence of NH 4 SP+/SP ion in an amount to provide a NH 4 SP+/SP/metal mass ratio of 0À05-1À6, and then recovering the complex ppt. from the soln. Finely divided carbon may be dispersed in the soln. in an amount to provide a C/metal mass ratio of 0À6-0À8 to produce a carbon-containing ppt. The NH 4 SP+/SP ion may be added to the soln. as (NH 4 ) 2 SO 4 , NH 4 Cl or aq. NH 3 . The resultant aq. soln. obtained after recovery of the ppt. may be further treated by the addition of more ferric salt in an amount to provide a Fe/metal mass ratio of 0À5-3À0 thereby to ppt. additional complex which may be recovered or dissolved in an aq. soln. of H 2 SO 4 or HCl, and then the dissolved complex recycled to the initial pptn. step. The initial aq. soln. of metal values may be obtained from their concentrates by fusing the concentrate with Na 2 CO 3 , leaching the fused mixture with water to produce an alkaline liquor, leaching the solid residue from the aq. leach with H 2 SO 4 to produce an acidic liquor and then combining the two leach solns. The acidic liquor may be used to dissolve the additional complex ppt. The dried ppt. may be reduced at elevated temp. to produce a metallic additive suitable for use in steel-making.