Patent ID: 7682419

Claim:
A method of processing sulfide minerals and concentrates by oxidation of sulfide minerals in an aqueous medium using an oxidizing agent which is one or more of nitric acid, nitrous acid and their oxides, the method comprising: subjecting in an oxidation reactor a slurry containing the sulfide minerals to oxidation under agitation and under controlled conditions of slurry acidity using the oxidizing agent which is one or more of nitric acid, nitrous acid and their oxides; forming in the oxidation reactor a sulfuric acid as a result of the sulfide oxidation; constantly neutralizing the sulfuric acid in the oxidation reactor using an acidity neutralizer to an acidity level at which no formation of elementary sulfur occurs; removing of heat released during the sulfide oxidation from the oxidation reactor; transferring NO from the oxidation reactor into a regeneration oxidizer; regenerating N 2 3 from the transferred NO using air or oxygen in the regeneration oxidizer; and transferring the regenerated N 2 O 3 into the oxidation reactor; wherein the temperature in the oxidation reactor is maintained in a range from 20 to 90° C. and wherein a liquid-to-solid ratio in the slurry in the oxidation reactor is between 1:1 to 5:1.