Patent ID: 8092765

Claim:
A method of processing non-ferrous smelting intermediates containing arsenic, comprising: a leaching step of oxidation leaching of a mixture slurry at an acidic pH to obtain a leaching solution, the mixture slurry being a mixture of a non-ferrous smelting intermediate containing arsenic in sulfide form and a non-ferrous smelting intermediate containing arsenic and copper as metal; a solution adjusting step of adding an oxidation agent to the leaching solution to oxidize trivalent arsenic to pentavalent arsenic and obtain an adjusted solution; and a crystallizing step of converting arsenic in the adjusted solution to scorodite crystals, wherein said leaching step comprises a first leaching step of performing leaching while maintaining a pH of 1.0 to 2.0 at a temperature of 80° C. or lower, while blowing air, oxygen, or a gas mixture of air and oxygen to the mixture slurry of the non-ferrous smelting intermediate containing arsenic in sulfide form and the non-ferrous smelting intermediate containing arsenic and copper as metal.