| 摘要 |
<p>1399620 Treating sulphide ores MOLYBDENUM CORP OF AMERICA 7 July 1972 [9 July 1971 20 March 1972] 31850/72 Heading C1A A sulphide ore containing a sulphide of a metal of Group Ib, IIb, IVb, VIa, VIIa or VIII of the Periodic table, arsenic, antimony or bismuth is oxidized by reacting the sulphide at above 150‹ C. in a reaction zone with less than the stoichiometric amount of nitric acid necessary to effect complete reduction, the oxides of nitrogen so formed being retained in the zone prior to reaction in the zone with oxygen and water to regenerate nitric acid. Oxygen may be introduced into the vessel at an overpressure. Sulphides exemplified are molybdenum, and antimony to produce molybdenum oxide MoO 3 and antimony oxide Sb 2 O 3 , Cu, Re, Fe, Cu, Zn, Ni, Co and Ag to produce the respective sulphates, although Example 6, by solvent extraction with C 8-10 trialkylamines in aromatic hydrocarbon. The strip solution is contacted with a hydrocarbon solution of a quaternary compound to separate Rh from Mo values and these are converted into ammonium perrhenate and ammonium molybdate.</p> |
