Oxidative heap leaching method

Abstract

A method for extracting copper from sulphide mineral ore, comprising the following steps: stacking the ore to form a pile (heap), a leaching step, irrigating the pile with a first irrigating solution containing an acidic nitrate solution and nitrite, thereby causing the oxidation of sulfide minerals inside the pile, oxidation of gaseous nitrogen oxide released during the oxidation of sulfide minerals inside the pile with oxygen to form nitrogen dioxide, and hydrolysis of nitrogen dioxide to form nitric acid and / or nitrous acid in the first irrigating solution inside the pile, to continue the leaching stage and reduce nitrogen oxide losses from the pile.