Oxidation process for releasing metal values in which nitric acid is regenerated in situ

摘要

An oxidation process for releasing a metal of interest in an ore is described. The process is especially useful for releasing a metal of interest entrapped in a refractory ore. The process comprises reacting the ore with nitric acid until sufficient oxidation has occurred to release the metal of interest so that it may be recovered by conventional techniques. Nitric acid is regenerated in situ by aerating the liquid medium and contacting it with the off gases generated by the oxidation. The process is continuous and the nitric acid is recycled to the reactor preferably after removal of accumulated sulfate and dissolved metal cations.